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Sample records for fenton oxidation process

  1. AN ADVANCED OXIDATION PROCESS : FENTON PROCESS

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    Engin GÜRTEKİN

    2008-03-01

    Full Text Available Biological wastewater treatment is not effective treatment method if raw wastewater contains toxic and refractory organics. Advanced oxidation processes are applied before or after biological treatment for the detoxification and reclamation of this kind of wastewaters. The advanced oxidation processes are based on the formation of powerful hydroxyl radicals. Among advanced oxidation processes Fenton process is one of the most promising methods. Because application of Fenton process is simple and cost effective and also reaction occurs in a short time period. Fenton process is applied for many different proposes. In this study, Fenton process was evaluated as an advanced oxidation process in wastewater treatment.

  2. Enhanced degradation of paracetamol by UV-C supported photo-Fenton process over Fenton oxidation.

    Science.gov (United States)

    Manu, B; Mahamood, S

    2011-01-01

    For the treatment of paracetamol in water, the UV-C Fenton oxidation process and classic Fenton oxidation have been found to be the most effective. Paracetamol reduction and chemical oxygen demand (COD) removal are measured as the objective functions to be maximized. The experimental conditions of the degradation of paracetamol are optimized by the Fenton process. Influent pH 3, initial H(2)O(2) dosage 60 mg/L, [H(2)O(2)]/[Fe(2+)] ratio 60 : 1 are the optimum conditions observed for 20 mg/L initial paracetamol concentration. At the optimum conditions, for 20 mg/L of initial paracetamol concentration, 82% paracetamol reduction and 68% COD removal by Fenton oxidation, and 91% paracetamol reduction and 82% COD removal by UV-C Fenton process are observed in a 120 min reaction time. By HPLC analysis, 100% removal of paracetamol is observed at the above optimum conditions for the Fenton process in 240 min and for the UV-C photo-Fenton process in 120 min. The methods are effective and they may be used in the paracetamol industry.

  3. SIMULTANEOUS DEGRADATION OF SOME PHTHALATE ESTERS UNDER FENTON AND PHOTO-FENTON OXIDATION PROCESSES

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    BELDEAN-GALEA M.S.

    2015-03-01

    Full Text Available In this study the assessment of the degradation efficiency of five phthalates, DEP, BBP, DEHP, DINP and DIDP, found in a mixture in a liquid phase, using the Fenton and Photo Fenton oxidation processes, was conducted. It was observed that the main parameters that influence the Fenton oxidative processes of phthalates were the concentration of the oxidizing agent, H2O2, the concentration of the catalyst used, Fe2+, the pH value, UV irradiation and the reaction time. For the Fenton oxidative process, the highest degradation efficiencies were 19% for DEP, 50% for BBP, 84% for DEHP, 90% for DINP and 48% for DIDP, when the experiments were carried out using concentrations of 20 mg L-1 phthalate mixture, 100 mg L-1 H2O2, 10 mg L-1 Fe2+ at a pH value of 3, with a total reaction time of 30 minutes. For the Photo-Fenton oxidative process carried out in the same conditions as Fenton oxidative process, it was observed that after an irradiation time of 90 minutes under UV radiation the degradation efficiencies of phthalates were improved, being 22% for DEP, 71% for BBP, 97% for DEHP, 97% for DINP and 81% for DIDP.

  4. Treatment of hazardous waste landfill leachate using Fenton oxidation process

    Science.gov (United States)

    Singa, Pradeep Kumar; Hasnain Isa, Mohamed; Ho, Yeek-Chia; Lim, Jun-Wei

    2018-03-01

    The efficiency of Fenton's oxidation was assessed in this study for hazardous waste landfill leachate treatment. The two major reagents, which are generally employed in Fenton's process are H2O2 as oxidizing agent and Fe2+ as catalyst. Batch experiments were conducted to determine the effect of experimental conditions viz., reaction time, molar ratio, and Fenton reagent dosages, which are significant parameters that influence the degradation efficiencies of Fenton process were examined. It was found that under the favorable experimental conditions, maximum COD removal was 56.49%. The optimum experimental conditions were pH=3, H2O2/Fe2+ molar ratio = 3 and reaction time = 150 minutes. The optimal amount of hydrogen peroxide and iron were 0.12 mol/L and 0.04 mol/L respectively. High dosages of H2O2 and iron resulted in scavenging effects on OH• radicals and lowered degradation efficiency of organic compounds in the hazardous waste landfill leachate.

  5. Oil refinery wastewater treatment using physicochemical, Fenton and Photo-Fenton oxidation processes.

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    Tony, Maha A; Purcell, Patrick J; Zhao, Yaqian

    2012-01-01

    The objective of this study was to investigate the application of advanced oxidation processes (AOPs) to the treatment of wastewaters contaminated with hydrocarbon oil. Three different oil-contaminated wastewaters were examined and compared: (i) a 'real' hydrocarbon wastewater collected from an oil refinery (Conoco-Phillips Whitegate refinery, County Cork, Ireland); (ii) a 'real' hydrocarbon wastewater collected from a car-wash facility located at a petroleum filling station; and (iii) a 'synthetic' hydrocarbon wastewater generated by emulsifying diesel oil and water. The AOPs investigated were Fe(2+)/H(2)O(2) (Fenton's reagent), Fe(2+)/H(2)O(2)/UV (Photo-Fenton's reagent) which may be used as an alternative to, or in conjunction with, conventional treatment techniques. Laboratory-scale batch and continuous-flow experiments were undertaken. The photo-Fenton parametric concentrations to maximize COD removal were optimized: pH = 3, H(2)O(2) = 400 mg/L, and Fe(2+) = 40 mg/L. In the case of the oil-refinery wastewater, photo-Fenton treatment achieved approximately 50% COD removal and, when preceded by physicochemical treatment, the percentage removal increased to approximately 75%.

  6. Advanced oxidation of Reactive Blue 181 solution: a comparison between Fenton and Sono-Fenton process.

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    Basturk, Emine; Karatas, Mustafa

    2014-09-01

    In this work, the decolorization of C.I. Reactive Blue 181 (RB181), an anthraquinone dye, by Ultrasound and Fe(2+) H2O2 processes was investigated. The effects of operating parameters, such as Fe(2+) dosage, H2O2 dosage, pH value, reaction time and temperature were examined. Process optimisation [pH, ferrous ion (Fe(2+)), hydrogen peroxide (H2O2), and reaction time], kinetic studies and their comparison were carried out for both of the processes. The Sono-Fenton process was performed by indirect sonication in an ultrasonic water bath, which was operated at a fixed 35-kHz frequency. The optimum conditions were determined as [Fe(2+)]=30 mg/L, [H2O2]=50 mg/L and pH=3 for the Fenton process and [Fe(2+)]=10 mg/L, [H2O2]=40 mg/L and pH=3 for the Sono-Fenton process. The colour removals were 88% and 93.5% by the Fenton and Sono-Fenton processes, respectively. The highest decolorization was achieved by the Sono-Fenton process because of the production of some oxidising agents as a result of sonication. The paper also discussed kinetic parameters. The decolorization kinetic of RB181 followed pseudo-second-order reaction (Fenton study) and Behnajady kinetics (Sono-Fenton study). Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Kinetic studies on the degradation of crystal violet by the Fenton oxidation process.

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    Wu, H; Fan, M M; Li, C F; Peng, M; Sheng, L J; Pan, Q; Song, G W

    2010-01-01

    The degradation of dye crystal violet (CV) by Fenton oxidation process was investigated. The UV-Vis spectrogram has shown that CV can be degraded effectively by Fenton oxidation process. Different system variables namely initial H(2)O(2) concentration, initial Fe(2 + ) concentration and reaction temperature, which have effect on the degradation of CV by Fenton oxidation process, have been studied systematically. The degradation kinetics of CV was also elucidated based on the experimental data. The degradation of CV obeys the first-order reaction kinetics. The kinetic model can be described as k=1.5 exp(-(7.5)/(RT))[H(2)O(2)](0)(0.8718)[Fe(2+)](0)(0.5062). According to the IR spectrogram, it is concluded that the benzene ring of crystal violet has been destroyed by Fenton oxidation. The result will be useful in treating dyeing wastewater containing CV by Fenton oxidation process.

  8. Evaluation of Efficacy of Advanced Oxidation Processes Fenton, Fenton-like and Photo-Fenton for Removal of Phenol from Aqueous Solutions

    International Nuclear Information System (INIS)

    Mofrad, M. R.; Akbari, H.; Miranzadeh, M. B.; Nezhad, M. E.; Atharizade, M.

    2015-01-01

    Contamination of water, soil and groundwater caused by aromatic compounds induces great concern in most world areas. Among organic pollutants, phenol is mostly considered dangerous due to its high toxicity for human and animal. Advanced oxidation processes (AOPs) is considered as a most efficient method also the best one for purifying organic compounds which are resistant to conventional physical and chemical processes. This experimental study was carried out in laboratory scale. First, a synthetic solution was made of phenol. Then, Fenton, Fenton-like and photo-Fenton processes were applied removing phenol from aquatic solution. The effects of Hydrogen Peroxide concentration, catalyst, pH and time were studied to phenol removal efficiency. Results showed that Photo-Fenton process with removal efficiency (97.5 percentage) is more efficient than Fenton and Fenton-like processes with removal efficiency (78.7 percentage and 82.5 percentage respectively), in pH=3, (H/sub 2/O/sub 2/)= 3mM, (Fe2+)= 0.1 mM, phenol concentration 100 mg L-1 and time reaction 60 min, the phenol removal was 97.5 percentage. (author)

  9. Comparative study of oxidation of dye-Reactive Black B by different advanced oxidation processes: Fenton, electro-Fenton and photo-Fenton

    International Nuclear Information System (INIS)

    Huang Yaohui; Huang Yifong; Chang Poshun; Chen Chuhyung

    2008-01-01

    This study makes a comparison between photo-Fenton and a novel electro-Fenton called Fered-Fenton to study the mineralization of 10,000 mg/L of dye-Reactive Black B (RBB) aqueous solution, which was chosen as the model dye contaminant. Results indicate that the traditional Fenton process only yields 70% mineralization. This result can be improved by using Fered-Fenton to yield 93% mineralization resulting from the action of ferrous ion regenerated on the cathode. Furthermore, photo-Fenton allows a fast and more complete destruction of dye solutions and as a result of the action of ferrous ion regenerated by UV irradiation yields more than 98% mineralization. In all treatments, the RBB is rapidly decayed to some carboxylic acid intermediates. The major intermediates found are formic acid and oxalic acid. This study finds that formic acid can be completely mineralized by photo-Fenton, but its destruction is problematic using the Fenton method. Oxalic acid is much more difficult to treat than other organic acids. It could get further mineralization with the use of the Fered-Fenton process

  10. Municipal solid waste landfill leachate treatment by fenton, photo-fenton and fenton-like processes: Effect of some variables

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    Zazouli, Mohammad Ali; Yousefi, Zabihollah; Eslami, Akbar; Ardebilian, Maryam Bagheri

    2012-01-01

    Abstract Advanced oxidation processes like Fenton and photo-Fenton have been effectively applied to oxidize the persistent organic compounds in solid waste leachate and convert them to unharmful materials and products. However, there are limited data about application of Fenton-like process in leachate treatment. Therefore, this study was designed with the objective of treating municipal landfill leachate by Fenton, Fenton-like and photo–Fenton processes to determine the effect of different v...

  11. Degradation of phthalate in aqueous solution by advanced oxidation process, photo-fenton

    International Nuclear Information System (INIS)

    Trabelsi, S.; Bellakhal, N.; Oturan, N.; Oturan, M.A.

    2009-01-01

    A photochemical method for degradation of persistent organic pollutants present in liquid effluents from the plastic industry and in the leaching described. This method, called P hoto-Fenton i nvolves the generation of radicals hydroxyl coupling between the Fenton reaction and photochemistry, OH radicals. Thus formed react with very high speeds, organic substances pollutants leading to their oxidation to total mineralization. In this study, we applied the process photo-Fenton treatment Plasticizers, Phthalates. For this, optimization of experimental parameters (namely the relationship between the concentrations of hydrogen peroxide and iron concentration catalyst) was performed. Under optimal conditions and determined the kinetics mineralization of phthalic anhydride by OH was studied. The overall results confirm the effectiveness of photo-Fenton process for the decontamination of liquid effluents responsible for persistent organic pollutants (Pop's).

  12. Degradation of sodium dodecyl sulphate in water using solar driven Fenton-like advanced oxidation processes

    International Nuclear Information System (INIS)

    Bandala, Erick R.; Pelaez, Miguel A.; Salgado, Maria J.; Torres, Luis

    2008-01-01

    Synthetic wastewater samples containing a model surfactant were treated using two different Fenton-like advanced oxidation processes promoted by solar radiation; the photo-Fenton reaction and Co/PMS/UV processes. Comparison between the different experimental conditions was performed by means of the overall surfactant degradation achieved and by obtaining the initial rate in the first 15 min of reaction (IR 15 ). It was found that, for dark Fenton reaction, the maximum surfactant degradation achieved was 14% under low iron and oxidant concentration. Increasing Fenton reagents by one magnitude order, surfactant degradation achieved 63% in 60 min. The use of solar radiation improved the reaction rate by 17% under same conditions and an additional increase of 12.5% was obtained by adjusting initial pH to 2. IR 15 values for dark and irradiated Fenton reactions were 0.143 and 0.154 mmol/min, respectively, for similar reaction conditions and this value increased to 0.189 mmol/min when initial pH was adjusted. The use of the Co/PMS system allow us to determine an increase in the degradation rate, for low reaction conditions (1 mM of transition metal; 4 mM oxidant) similar to those used in dark Fenton reaction. Surfactant degradation increased from 3%, for Fenton reaction, to 44.5% in the case of Co/PMS. When solar irradiation was included in the experiments, under same reaction conditions described earlier, surfactant degradation up to 64% was achieved. By increasing Co/PMS reagent concentration by almost 9 times under irradiated conditions, almost complete (>99%) surfactant degradation was reached in 5 min. Comparing IR 15 values for Co/PMS and Co/PMS/UV, it allow us to observe that the use of solar radiation increased the degradation rate in one magnitude order when compared with dark experiments and further increase of reagent concentration increased reaction rate twice

  13. The catalytic oxidation of malachite green by the microwave-Fenton processes.

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    Zheng, Huaili; Zhang, Huiqin; Sun, Xiaonan; Zhang, Peng; Tshukudu, Tiroyaone; Zhu, Guocheng

    2010-01-01

    Catalytic oxidation of malachite green using the microwave-Fenton process was investigated. 0% of malachite green de-colorization using the microwave process and 23.5% of malachite green de-colorization using the Fenton process were observed within 5 minutes. In contrast 95.4% of malachite green de-colorization using the microwave-Fenton was observed in 5 minutes. During the microwave-Fenton process, the optimum operating conditions for malachite green de-colorization were found to be 3.40 of initial pH, 0.08 mmol/L of Fe2+ concentration and 12.5 mmol/L of H2O2 concentration. Confirmatory tests were carried out under the optimum conditions and the COD removal rate of 82.0% and the de-colorization rate of 99.0% were observed in 5 minutes. The apparent kinetics equation of -dC/dt=0.0337 [malachite green]0.9860[Fe2+)]0.8234[H2O2]0.1663 for malachite green de-colorization was calculated, which implied that malachite green was the dominant factor in determining the removal efficiency of malachite green based on microwave-Fenton process.

  14. Removal of refractory organics in nanofiltration concentrates of municipal solid waste leachate treatment plants by combined Fenton oxidative-coagulation with photo--Fenton processes.

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    Li, Jiuyi; Zhao, Lei; Qin, Lele; Tian, Xiujun; Wang, Aimin; Zhou, Yanmei; Meng, Liao; Chen, Yong

    2016-03-01

    Removal of the refractory organic matters in leachate brines generated from nanofiltration unit in two full-scale municipal solid waste landfill leachate treatment plants was investigated by Fenton oxidative-coagulation and ultraviolet photo - Fenton processes in this study. Fenton oxidative-coagulation was performed under the condition of an initial pH of 5.0 and low H2O2/Fe(2+) ratios. After precipitate separation, the remaining organic constituents were further oxidized by photo - Fenton process. For both leachate brines with varying pollution strength, more than 90% COD and TOC reductions were achieved at H2O2/Fe(2+) dosages of 35 mM/8 mM and 90 mM/10 mM, respectively. The effluent COD ranged 120-160 mg/L under the optimal operating conditions, and the biodegradability was increased significantly. Fenton oxidative-coagulation was demonstrated to contribute nearly 70% overall removal of organic matters. In the combined processes, the efficiency of hydrogen peroxide varied from 216 to 228%, which may significantly reduce the operating cost of conventional Fenton method. Six phthalic acid esters and thirteen polycyclic aromatic hydrocarbons were found in leachate brines, and, on the average, around 80% phthalic acid esters and 90% polycyclic aromatic hydrocarbons were removed by the combined treatments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Decolorization of Industrial Waste Using Fenton Process and Photo Fenton

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    Wardiyati, Siti; Dewi, Sari Hasnah; Fisli, Adel

    2013-01-01

    Industrial waste water decolorization has been done using the method of Fenton and Photo Fenton. The experiment was conducted in order to obtain the optimum process conditions for industrial waste treatment method with Fenton and Photo Fenton. Industrial waste used in this experiment waste of blue batik making process derived from Rara Djograng Batik Yogyakarta. Factors were studied in this research are the effect of the amount of catalyst FeSO4.7H2O, the amount of oxidant H2O2, and the time ...

  16. Treatment of oilfield wastewater by combined process of micro-electrolysis, Fenton oxidation and coagulation.

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    Zhang, Zhenchao

    2017-12-01

    In this study, a combined process was developed that included micro-electrolysis, Fenton oxidation and coagulation to treat oilfield fracturing wastewater. Micro-electrolysis and Fenton oxidation were applied to reduce chemical oxygen demand (COD) organic load and to enhance organic components gradability, respectively. Orthogonal experiment were employed to investigate the influence factors of micro-electrolysis and Fenton oxidation on COD removal efficiency. For micro-electrolysis, the optimum conditions were: pH, 3; iron-carbon dosage, 50 mg/L; mass ratio of iron-carbon, 2:3; reaction time, 60 min. For Fenton oxidation, a total reaction time of 90 min, a H 2 O 2 dosage of 12 mg/L, with a H 2 O 2 /Fe 2+ mole ratio of 30, pH of 3 were selected to achieve optimum oxidation. The optimum conditions in coagulation process: pH, cationic polyacrylamide dosage, mixing speed and time is 4.3, 2 mg/L, 150 rpm and 30 s, respectively. In the continuous treatment process under optimized conditions, the COD of oily wastewater fell 56.95%, 46.23%, 30.67%, respectively, from last stage and the total COD removal efficiency reached 83.94% (from 4,314 to 693 mg/L). In the overall treatment process under optimized conditions, the COD of oily wastewater was reduced from 4,314 to 637 mg/L, and the COD removal efficiency reached 85.23%. The contribution of each stage is 68.45% (micro-electrolysis), 24.07% (Fenton oxidation), 7.48% (coagulation), respectively. Micro-electrolysis is the uppermost influencing process on COD removal. Compared with the COD removal efficiency of three processes on raw wastewater under optimized conditions: the COD removal efficiency of single micro-electrolysis, single Fenton oxidation, single coagulation is 58.34%, 44.88% and 39.72%, respectively. Experiments proved the effect of combined process is marvelous and the overall water quality of the final effluent could meet the class III national wastewater discharge standard of petrochemical industry of China

  17. Heterocatalytic Fenton oxidation process for the treatment of tannery effluent: kinetic and thermodynamic studies.

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    Karthikeyan, S; Ezhil Priya, M; Boopathy, R; Velan, M; Mandal, A B; Sekaran, G

    2012-06-01

    BACKGROUND, AIM, SCOPE: Treatment of wastewater has become significant with the declining water resources. The presence of recalcitrant organics is the major issue in meeting the pollution control board norms in India. The theme of the present investigation was on partial or complete removal of pollutants or their transformation into less toxic and more biodegradable products by heterogeneous Fenton oxidation process using mesoporous activated carbon (MAC) as the catalyst. Ferrous sulfate (FeSO(4)·7H(2)O), sulfuric acid (36 N, specific gravity 1.81, 98% purity), hydrogen peroxide (50% v/v) and all other chemicals used in this study were of analytical grade (Merck). Two reactors, each of height 50 cm and diameter 6 cm, were fabricated with PVC while one reactor was packed with MAC of mass 150 g and other without MAC served as control. The oxidation process was presented with kinetic and thermodynamic constants for the removal of COD, BOD, and TOC from the wastewater. The activation energy (Ea) for homogeneous and heterogeneous Fenton oxidation processes were 44.79 and 25.89 kJ/mol, respectively. The thermodynamic parameters ΔG, ΔH, and ΔS were calculated for the oxidation processes using Van't Hoff equation. Furthermore, the degradation of organics was confirmed through FTIR and UV-visible spectroscopy, and cyclic voltammetry. The heterocatalytic Fenton oxidation process efficiently increased the biodegradability index (BOD/COD) of the tannery effluent. The optimized conditions for the heterocatalytic Fenton oxidation of organics in tannery effluent were pH 3.5, reaction time-4 h, and H(2)O(2)/FeSO(4)·7H(2)O in the molar ratio of 2:1.

  18. Treating leachate by Fenton oxidation

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    Roger Iván Méndez Novelo

    2010-01-01

    Full Text Available Leachates are formed from liquids, mainly rainwater, percolating through solid wastes during stabilisation. Their composition is variable and highly toxic; leachate treatment is therefore a complex task. Leachates represent a high risk to health due to the Yucatan Peninsula’s highly permeable soil. The results are presented from applying the Fenton process to treating leachate from the sanitary Merida landfill, Yucatan, Mexico. The Fenton process consists of treating the contaminant load with an H2O2 and FeSO4 combination in acidic conditions. Optimal reaction time, pH value, Fenton reagent dose, post treatment coagulation – flocculation doses and increased biodegradability index were all determined. Optimal oxidation conditions and doses were 202+ minute contact time, 4 pH, 600 mg/L H2O2 concentration and 1,000 mg/L Fe. Average organic matter removal rate, measured as CODS and TOC, were 78% and 87% respectively. The biodegradability index increased from 0.07 to 0.11 during the Fenton process and up to 0.13 when the Fenton process was followed by coagulation-flocculation.

  19. REMOVAL OF REMAZOL ROSSO RB DYE FROM AQUEOUS EFFLUENTS BY HOMOGENOUS FENTON OXIDATION PROCESSES

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    Carmen Zaharia

    2014-06-01

    Full Text Available The paper presents some data from our laboratory-setup experiments of homogenous oxidative processes with hydrogen peroxide (i.e. advanced Fenton oxidation processes applied for Remazol Rosso RB dye-containing aqueous systems, especially textile effluents. Therefore, some different operating parameters (including pH, concentration of dye, H2O2 and ferrous ions, oxidation time, temperature, stirring regime, among its were tested for determination of the best performance in effluent decoloration and dye removal, meaning the optimal values of each studied parameters for highest decoloration or dye removal.

  20. Disintegration and dissolution of spent radioactive cationic exchange resins using Fenton-like oxidation process

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Zhong; Xu, Lejin [Collaborative Innovation Center for Advanced Nuclear Energy Technology, INET, Tsinghua University, Beijing 100084 (China); Wang, Jianlong, E-mail: wangjl@tsinghua.edu.cn [Collaborative Innovation Center for Advanced Nuclear Energy Technology, INET, Tsinghua University, Beijing 100084 (China); Beijing Key Laboratory of Radioactive Wastes Treatment, Tsinghua University, Beijing 100084 (China)

    2015-09-15

    Highlights: • The spent radioactive resins could be oxidized by Fenton-like process. • The influencing factors on resin oxidation were evaluated. • Chemical oxygen demand (COD) reduction rate was more than 99%. • SEM and Raman spectrum were used to analyze the resins morphological change. - Abstract: The treatment and disposal of the spent radioactive resins is essential for the sustainable development of the nuclear industry. In this paper, the disintegration and dissolution of spent cationic resins were studied by Fenton-like process. The influencing factors on resin dissolution, such as pH, temperature, type and concentration of catalysts were evaluated. The results showed that the spent resins could be effectively dissolved at pH < 1, [Fe{sup 2+}] = 0.2 M and T = 97 ± 2 °C. Chemical oxygen demand (COD) reduction rate was more than 99%. The scanning electron microscopy and the Raman spectrum were used to observe the morphological changes of the spent resins during the dissolution process. Fenton-like oxidation is an efficient method for the volume reduction and stabilization of the spent resins before further immobilization.

  1. Disintegration and dissolution of spent radioactive cationic exchange resins using Fenton-like oxidation process

    International Nuclear Information System (INIS)

    Wan, Zhong; Xu, Lejin; Wang, Jianlong

    2015-01-01

    Highlights: • The spent radioactive resins could be oxidized by Fenton-like process. • The influencing factors on resin oxidation were evaluated. • Chemical oxygen demand (COD) reduction rate was more than 99%. • SEM and Raman spectrum were used to analyze the resins morphological change. - Abstract: The treatment and disposal of the spent radioactive resins is essential for the sustainable development of the nuclear industry. In this paper, the disintegration and dissolution of spent cationic resins were studied by Fenton-like process. The influencing factors on resin dissolution, such as pH, temperature, type and concentration of catalysts were evaluated. The results showed that the spent resins could be effectively dissolved at pH < 1, [Fe 2+ ] = 0.2 M and T = 97 ± 2 °C. Chemical oxygen demand (COD) reduction rate was more than 99%. The scanning electron microscopy and the Raman spectrum were used to observe the morphological changes of the spent resins during the dissolution process. Fenton-like oxidation is an efficient method for the volume reduction and stabilization of the spent resins before further immobilization

  2. Fenton Process Coupled to Ultrasound and UV Light Irradiation for the Oxidation of a Model Pollutant

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    Karen E. Barrera-Salgado

    2016-01-01

    Full Text Available The Fenton process coupled to photosonolysis (UV light and Us, using Fe2O3 catalyst supported on Al2O3, was used to oxidize a model pollutant like acid green 50 textile dye (AG50. Dye degradation was followed by AG50 concentration decay analyses. It was observed that parameters like iron content on a fixed amount of catalyst supporting material, catalyst annealing temperature, initial dye concentration, and the solution pH influence the overall treatment efficiency. High removal efficiencies of the model pollutant are achieved. The stability and reusability tests of the Fe2O3 catalyst show that the catalyst can be used up to three cycles achieving high discoloration. Thus, this catalyst is highly efficient for the degradation of AG50 in the Fenton process.

  3. Evaluation of the resin oxidation process using Fenton's reagent

    International Nuclear Information System (INIS)

    Araujo, Leandro G.; Goes, Marcos M.; Marumo, Julio T.

    2013-01-01

    The ion exchange resin is considered radioactive waste after its final useful life in nuclear reactors. Usually, this type of waste is treated with the immobilization in cement Portland, in order to form a solid monolithic matrix, reducing the possibility of radionuclides release in to environment. Because of the characteristic of expansion and contraction of the resins in presence of water, its incorporation in the common Portland cement is limited in 10% in direct immobilization, causing high costs in the final product. A pre-treatment would be able to reduce the volume, degrading the resins and increasing the load capacity of this material. This paper is about a method of degradation of ion spent resins from the nuclear research reactor of Nuclear and Energy Research Institute (IPEN/CNEN-SP), Brazil, using the Fenton's reagent. The resin evaluated was a mixture of cationic and anionic resins. The reactions were conducted by varying the concentration of the catalyst (25 to 80 mM), with and without external heat. The time of reaction was two hours. The concentration of 50 mM of catalyst was the most effective in degrading approximately 99%. The resin degradation was confirmed by the presence of CaCO 3 as a white precipitate resulting from the reaction between the Ca(OH) 2 and the CO 2 from the resin degradation. It was possible to degrade the resins without external heating. The calcium carbonates showed no correlation with the residual resin mass. (author)

  4. Soil remediation using a coupled process: soil washing with surfactant followed by photo-Fenton oxidation

    International Nuclear Information System (INIS)

    Villa, Ricardo D.; Trovo, Alam G.; Nogueira, Raquel F. Pupo

    2010-01-01

    In the present work the use of a coupled process, soil washing and photo-Fenton oxidation, was investigated for remediation of a soil contaminated with p,p'-DDT (DDT) and p,p'-DDE (DDE), and a soil artificially contaminated with diesel. In the soil washing experiments, Triton X-100 (TX-100) aqueous solutions were used at different concentrations to obtain wastewaters with different compositions. Removal efficiencies of 66% (DDT), 80% (DDE) and 100% (diesel) were achieved for three sequential washings using a TX-100 solution strength equivalent to 12 times the effective critical micelle concentration of the surfactant (12 CMC eff ). The wastewater obtained was then treated using a solar photo-Fenton process. After 6 h irradiation, 99, 95 and 100% degradation efficiencies were achieved for DDT, DDE and diesel, respectively. In all experiments, the concentration of dissolved organic carbon decreased by at least 95%, indicating that residual concentration of contaminants and/or TX-100 in the wastewater was very low. The co-extraction of metals was also evaluated. Among the metals analyzed (Pb, Cr, Ni, Cu, Cd, Mn and Co), only Cr and Mn were detected in the wastewater at concentrations above the maximum value permitted by current Brazilian legislation. The effective removal of contaminants from soil by the TX-100 washing process, together with the high degradation efficiency of the solar photo-Fenton process, suggests that this procedure could be a useful option for soil remediation.

  5. Soil remediation using a coupled process: soil washing with surfactant followed by photo-Fenton oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Villa, Ricardo D., E-mail: ricardovilla@ufmt.br [UNESP - Sao Paulo State University, Institute of Chemistry of Araraquara, Department of Analytical Chemistry, P.O. Box 355, 14801-970 Araraquara, SP (Brazil); Trovo, Alam G., E-mail: alamtrovo@smail.ufsm.br [UNESP - Sao Paulo State University, Institute of Chemistry of Araraquara, Department of Analytical Chemistry, P.O. Box 355, 14801-970 Araraquara, SP (Brazil); Nogueira, Raquel F. Pupo, E-mail: nogueira@iq.unesp.br [UNESP - Sao Paulo State University, Institute of Chemistry of Araraquara, Department of Analytical Chemistry, P.O. Box 355, 14801-970 Araraquara, SP (Brazil)

    2010-02-15

    In the present work the use of a coupled process, soil washing and photo-Fenton oxidation, was investigated for remediation of a soil contaminated with p,p'-DDT (DDT) and p,p'-DDE (DDE), and a soil artificially contaminated with diesel. In the soil washing experiments, Triton X-100 (TX-100) aqueous solutions were used at different concentrations to obtain wastewaters with different compositions. Removal efficiencies of 66% (DDT), 80% (DDE) and 100% (diesel) were achieved for three sequential washings using a TX-100 solution strength equivalent to 12 times the effective critical micelle concentration of the surfactant (12 CMC{sub eff}). The wastewater obtained was then treated using a solar photo-Fenton process. After 6 h irradiation, 99, 95 and 100% degradation efficiencies were achieved for DDT, DDE and diesel, respectively. In all experiments, the concentration of dissolved organic carbon decreased by at least 95%, indicating that residual concentration of contaminants and/or TX-100 in the wastewater was very low. The co-extraction of metals was also evaluated. Among the metals analyzed (Pb, Cr, Ni, Cu, Cd, Mn and Co), only Cr and Mn were detected in the wastewater at concentrations above the maximum value permitted by current Brazilian legislation. The effective removal of contaminants from soil by the TX-100 washing process, together with the high degradation efficiency of the solar photo-Fenton process, suggests that this procedure could be a useful option for soil remediation.

  6. Municipal solid waste landfill leachate treatment by fenton, photo-fenton and fenton-like processes: Effect of some variables

    Science.gov (United States)

    2012-01-01

    Advanced oxidation processes like Fenton and photo-Fenton have been effectively applied to oxidize the persistent organic compounds in solid waste leachate and convert them to unharmful materials and products. However, there are limited data about application of Fenton-like process in leachate treatment. Therefore, this study was designed with the objective of treating municipal landfill leachate by Fenton, Fenton-like and photo–Fenton processes to determine the effect of different variables, by setting up a pilot system. The used leachate was collected from a municipal unsanitary landfill in Qaem-Shahr in the north of Iran. Fenton and Fenton-like processes were conducted by Jar-test method. Photo-Fenton process was performed in a glass photo-reactor. In all processes, H2O2 was used as the oxidant. FeSO4.7H2O and FeCl3.6H2O were used as reagents. All parameters were measured based on standard methods. The results showed that the optimum concentration of H2O2 was equal to 5 g/L for the Fenton-like process and 3 g/L for the Fenton and photo-Fenton processes. The optimum ratio of H2O2: Fe+2/Fe+3 were equal to 8:1 in all processes. At optimum conditions, the amount of COD removal was 69.6%, 65.9% and 83.2% in Fenton, Fenton-like and photo–Fenton processes, respectively. In addition, optimum pH were 3, 5 and 3 and the optimum contact time were 150, 90 and 120 minutes, for Fenton, Fenton-like and photo–Fenton processes, respectively. After all processes, the biodegradability (BOD5/COD ratio) of the treated leachate was increased compared to that of the raw leachate and the highest increase in BOD5/COD ratio was observed in the photo-Fenton process. The efficiency of the Fenton-like process was overally less than Fenton and photo-Fenton processes, meanwhile the Fenton-like process was at higher pH and did not show problems. PMID:23369204

  7. Removal of citrate and hypophosphite binary components using Fenton, photo-Fenton and electro-Fenton processes

    Institute of Scientific and Technical Information of China (English)

    Yao-Hui Huang; Hsiao-Ting Su; Li-Way Lin

    2009-01-01

    Both citrate and hypophosphite in aqueous solution were degraded by advanced oxidation processes (Fe2+/H2O2, UV/Fe2+/H2O2, and electrolysis/ Fe2+/H2O2) in this study. Comparison of these techniques in oxidation efficiency was undertaken. It was found that Fenton process could not degrade completely citrate in the presence of hypophosphite since it caused a series inhibition. Therefore, UV light (photo-Fenton) or electron current (electro-Fenton) was applied to improve the degradation efficiency of the Fenton process. Results showed that both photo-Fenton and electro-Fenton processes could overcome the inhibition of hypophosphite, especially the electro-Fenton.

  8. Removal of Acid Yellow 17 Dye by Fenton Oxidation Process

    Science.gov (United States)

    Khan, Jehangeer; Sayed, Murtaza; Ali, Fayaz; Khan, Hasan Mahmood

    2018-05-01

    In the present research work the degradation of acid yellow 17 (AY 17) by H2O2/Fe2+ was investigated. The effect of various conditions such as pH value, temperature, conc. of H2O2, Fe2+, conc. of AY 17 were studied. Additionally the scavenging effects of various anions such as Cl-, SO42-, CO32- and HCO3-, on percent degradation of AY 17 were examined. It was found that these anions decrease percent degradation as well as rate of degradation reaction. The optimum conditions were determined as [AY 17]=[Fe2+]=0.06 mM [H2O2]=0.9 mM, and pH 3.0 for 60 min of reaction time. It was found that at optimum conditions 89% degradation of AY17 was achieved. The degradation kinetics of AY17 followed pseudo-first-order reaction kinetics. Thermodynamic studies under natural conditions showed positive value of ΔH (enthalpy) which indicates the degradation process is endothermic.

  9. A combined process of adsorption and Fenton-like oxidation for furfural removal using zero-valent iron residue.

    Science.gov (United States)

    Li, Furong; Bao, Jianguo; Zhang, Tian C; Lei, Yutian

    2015-01-01

    In this study, the feasibility of using a combined adsorption and Fenton-like oxidation process (with zero-valent iron (ZVI) residue from heat wraps as an absorbent and catalyst) to remove furfural in the solution was evaluated. The influencing parameters (e.g. pH, H2O2 concentration, initial furfural concentration) and the reusability of ZVI residue (to replace the iron powder) were estimated. The ZVI residue was found to have much better adsorption effect on furfural at pH 2.0 compared with pH 6.7. For Fenton-like reaction alone with ZVI residue, the highest furfural removal of 97.5% was observed at the concentration of 0.176 mol/L H2O2, and all of the samples had >80% removal efficiency at different initial furfural concentrations of 2, 10, 20, 30 and 40 mmol/L. However, with a combined adsorption and Fenton-like oxidation, the removal efficiency of furfural was nearly 100% for all treatments. The ZVI residue used for furfural removal was much better than that of iron powder in the Fenton-like reaction at a seven-cycle experiment. This study suggests the combined process of adsorption and Fenton-like oxidation using ZVI residue is effective for the treatment of furfural in the liquid.

  10. Investigation the Efficiency of Combined Coagulation and Advanced Oxidation by Fenton Process in the Removal of Clarithromycin Antibiotic COD

    Directory of Open Access Journals (Sweden)

    Ahmad Reza Yazdanbakhsh

    2012-07-01

    Full Text Available Antibiotics are considered among the major pollutants in water environments. In this study, removal of Claritromycine antibiotic has been studied from synthetic wastewater by combined coagulation and advanced oxidation processes. This study, was done in laboratory scale .  Samples of synthetic wastewater  were prepared from Claritromycin antibiotic. Concentration of samples were 200 mg/l. COD index was selected as a parameter evaluated in this study. In the first stage, coagulation process was done on synthetic wastewater and the proper condition was achieved (proper coagulant, optimum pH, dosage of coagulant. After that, Fenton oxidation process was done, on the effluent of coagulation process. In Fenton process the influence of pH, Fe2+ and hydrogen peroxide were studied on the removal efficiency of Claritromycin antibiotic and the optimum values for each parameter were determined. According to the results of this study, Poly Aluminum Chloride (PAC  is the proper coagulant. With pH equal to 7 and 100 mg/l PAC, 84.37% removal of Claritromycine was achieved.  For fenton process, optimum parameters for the removal of Claritromycin were determined. The optimum condition for fenton process were, pH= 7, Fe2+ equal to 0.45 mmol/ l , hydrogen proxide equal to 0. 16 mmol/l, ratio of H2O2/Fe2+ equal to 0.4 and detention time of 1hour .With Applying of optimum conditions for combined coagulation and Fenton processes, 96.3% removal of Claritromycin was obtained.

  11. Oxidation of microcystin-LR by the Fenton process : Kinetics, degradation intermediates, water quality and toxicity assessment

    NARCIS (Netherlands)

    Park, Jeong-Ann; Yang, Boram; Park, Chanhyuk; Choi, Jae-Woo; van Genuchten, Case M.|info:eu-repo/dai/nl/413489647; Lee, Sang-Hyup

    2017-01-01

    The Fenton process was assessed as a cost-effective technology for the removal of Microcystin-LR (MC-LR) among UV, UV/H2O2, and Fenton process according to efficiency and electrical energy per order (EE/O). The determined practical concentrations of the Fenton reagents were 5 mg/L Fe(II) and 5 mg/L

  12. Pretreatment of 2,4-dinitroanisole (DNAN) producing wastewater using a combined zero-valent iron (ZVI) reduction and Fenton oxidation process

    International Nuclear Information System (INIS)

    Shen, Jinyou; Ou, Changjin; Zhou, Zongyuan; Chen, Jun; Fang, Kexiong; Sun, Xiuyun; Li, Jiansheng; Zhou, Lin; Wang, Lianjun

    2013-01-01

    Highlights: • ZVI-Fenton process was conducted for DNAN producing wastewater pretreatment. • Transformation of nitro to amino group by ZVI overcomes the oxidative hindrance. • Subsequent Fenton process is efficient for the removal of aromatic compounds. • ABR-MBBR process is efficient for the polishing of ZVI-Fenton effluent. -- Abstract: A combined zero-valent iron (ZVI) reduction and Fenton oxidation process was tested for the pretreatment of 2,4-dinitroanisole (DNAN) producing wastewater. Operating conditions were optimized and overall performance of the combined process was evaluated. For ZVI process, almost complete reduction of nitroaromatic compounds was observed at empty bed contact time (EBCT) of 8 h. For Fenton process, the optimal pH, H 2 O 2 to Fe(II) molar ratio, H 2 O 2 dosage and hydraulic retention time (HRT) were found to be 3.0, 15, 0.216 mol/L and 5 h, respectively. After pretreatment by the combined ZVI-Fenton process under the optimal conditions, aromatic organic compound removal was as high as 77.2%, while the majority of COD remained to be further treated by sequent biological process. The combined anaerobic-aerobic process consisted of an anaerobic baffled reactor (ABR) and a moving-bed biofilm reactor (MBBR) was operated for 3 months, fed with ZVI-Fenton effluent. The results revealed that the coupled ZVI-Fenton-ABR-MBBR system was significantly efficient in terms of correcting the effluent's main parameters of relevance, mainly aromatic compounds concentration, COD concentration, color and acute toxicity. These results indicate that the combined ZVI-Fenton process offers bright prospects for the pretreatment of wastewater containing nitroaromatic compounds

  13. Optimizing the treatment of landfill leachate by conventional Fenton and photo-Fenton processes

    International Nuclear Information System (INIS)

    Hermosilla, Daphne; Cortijo, Manuel; Huang, Chin Pao

    2009-01-01

    Landfill, a matured and economically appealing technology, is the ultimate approach for the management of municipal solid wastes. However, the inevitable generation of leachate from landfill requires further treatment. Among the various leachate treatment technologies available, advanced oxidation processes (AOPs) are among powerful methods to deal with the refractory organic constituents, and the Fenton reagent has evolved as one promising AOPs for the treatment of leachates. Particularly, the combination of UV-radiation with Fenton's reagent has been reported to be a method that allows both the photo-regeneration of Fe 2+ and photo-decarboxylation of ferric carboxylates. In this study, Fenton and photo-Fenton processes were fine tuned for the treatment of leachates from the Colmenar Viejo (Madrid, Spain) Landfill. Results showed that it is possible to define a set of conditions under which the same COD and TOC removals (approx 70%) could be achieved with both the conventional and photo-Fenton processes. But Fenton process generated an important quantity of iron sludge, which will require further disposal, when performed under optimal COD removal conditions. Furthermore conventional Fenton process was able to achieve slightly over an 80% COD removal from a 'young' leachate, while for 'old' and 'mixed' leachates was close to a 70%. The main advantage showed by the photo-assisted Fenton treatment of landfill leachate was that it consumed 32 times less iron and produced 25 times less sludge volume yielding the same COD removal results than a conventional Fenton treatment.

  14. Sequential application of Fenton and ozone-based oxidation process for the abatement of Ni-EDTA containing nickel plating effluents.

    Science.gov (United States)

    Zhao, Zilong; Liu, Zekun; Wang, Hongjie; Dong, Wenyi; Wang, Wei

    2018-07-01

    Treatment of Ni-EDTA in industrial nickel plating effluents was investigated by integrated application of Fenton and ozone-based oxidation processes. Determination of integrated sequence found that Fenton oxidation presented higher apparent kinetic rate constant of Ni-EDTA oxidation and capacity for contamination load than ozone-based oxidation process, the latter, however, was favorable to guarantee the further mineralization of organic substances, especially at a low concentration. Serial-connection mode of two oxidation processes was appraised, Fenton effluent after treated by hydroxide precipitation and filtration negatively affected the overall performance of the sequential system, as evidenced by the removal efficiencies of Ni 2+ and TOC dropping from 99.8% to 98.7%, and from 74.8% to 66.6%, respectively. As a comparison, O 3 /Fe 2+ oxidation process was proved to be more effective than other processes (e.g. O 3 -Fe 2+ , O 3 /H 2 O 2 /Fe 2+ , O 3 /H 2 O 2 -Fe 2+ ), and the final effluent Ni 2+ concentration could satisfied the discharge standard (Fenton reaction, initial influent pH of 3.0, O 3 dosage of 252 mg L -1 , Fe 2+ of 150 mg L -1 , and reaction time of 30 min for O 3 /Fe 2+ oxidation). Furthermore, pilot-scale test was carried out to study the practical treatability towards the real nickel plating effluent, revealing the effective removal of some other co-existence contaminations. And Fenton reaction has contributed most, with the percentage ranging from 72.41% to 93.76%. The economic cost advantage made it a promising alternative to the continuous Fenton oxidation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Alkydic resin wastewaters treatment by fenton and photo-Fenton processes

    International Nuclear Information System (INIS)

    Schwingel de Oliveira, Isadora; Viana, Lilian; Verona, Cenira; Fallavena, Vera Lucia Vargas; Azevedo, Carla Maria Nunes; Pires, Marcal

    2007-01-01

    Advanced oxidation processes are an emerging option to treatment of the painting industry effluents. The aim of this study was to compare the effectiveness of the Fenton and photo-Fenton processes in chemical oxygen demand (COD), total organic carbon (TOC) and phenolic compounds removal from wastewaters generated during alkydic resins manufacture. The optimized treatment conditions are the following: pH 3.0, 15.15 x 10 -3 mol L -1 FeSO 4 and 0.30 mol L -1 H 2 O 2 for a reaction time of 6 h. photo-Fenton experiments were carried out in the presence of sunlight or artificial radiation and complementary additions of H 2 O 2 were made for all experiments. The best results were obtained with photo-Fenton process assisted with solar radiation, with reductions of 99.5 and 99.1% of COD and TOC levels, respectively. Fenton and photo-Fenton (with artificial irradiation) processes presented lower but not insignificant removals, within 60-80% reduction for both COD and TOC. In addition, an excellent removal (95%) of total phenols was obtained using photo-Fenton process assisted with artificial irradiation. This study demonstrated that the use of photo-Fenton process on alkydic resins wastewater treatment is very promising especially when solar light is used

  16. DI-(2-ETHYLHEXYL PHTHALATE OXIDATIVE DEGRADATION BY FENTON PROCESS IN SYNTHETIC AND REAL PETROCHEMICAL WASTEWATER

    Directory of Open Access Journals (Sweden)

    R. Esmaeli

    2011-09-01

    Full Text Available Di-(2-Ethylhexyl phthalate (DEHP belongs to the class of phthalate esters and is used as an additive in many products including plastics, paints and inks or as a solvent in industrial formulations. The degradation of DEHP in aqueous solution using oxidative Fenton reaction (H2O2/Fe2+ was carried out in this study. It was found that H2O2 concentration, Fe2+ concentration, and pH were the three main factors that could significantly influence the degradation rates of DEHP. The highest degradation percentage (85.6 % of DEHP was observed within 60 min at pH 3 in H2O2/Fe2+ system. The results of our study suggested that the concentration with 90 mg/L H2O2, 5 mg/L Fe2+, and 20 mg/L DEHP in the solution at pH 3 were the optimal conditions. The optimized reaction parameters were preceded for treatment of real wastewater obtained from a petrochemical plant.

  17. Optimizing the treatment of landfill leachate by conventional Fenton and photo-Fenton processes

    Energy Technology Data Exchange (ETDEWEB)

    Hermosilla, Daphne, E-mail: dhermosilla@quim.ucm.es [Departamento de Ingenieria Quimica, Facultad de Ciencias Quimicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); Cortijo, Manuel [U.D. Operaciones Basicas, Departamento de Ingenieria Forestal, E.T.S.I. Montes, Universidad Politecnica de Madrid, Avda. Ramiro de Maeztu s/n, 28040 Madrid (Spain); Huang, Chin Pao [Department of Civil and Environmental Engineering, 352C DuPont Hall, University of Delaware, Newark, DE 19716 (United States)

    2009-05-15

    Landfill, a matured and economically appealing technology, is the ultimate approach for the management of municipal solid wastes. However, the inevitable generation of leachate from landfill requires further treatment. Among the various leachate treatment technologies available, advanced oxidation processes (AOPs) are among powerful methods to deal with the refractory organic constituents, and the Fenton reagent has evolved as one promising AOPs for the treatment of leachates. Particularly, the combination of UV-radiation with Fenton's reagent has been reported to be a method that allows both the photo-regeneration of Fe{sup 2+} and photo-decarboxylation of ferric carboxylates. In this study, Fenton and photo-Fenton processes were fine tuned for the treatment of leachates from the Colmenar Viejo (Madrid, Spain) Landfill. Results showed that it is possible to define a set of conditions under which the same COD and TOC removals (approx 70%) could be achieved with both the conventional and photo-Fenton processes. But Fenton process generated an important quantity of iron sludge, which will require further disposal, when performed under optimal COD removal conditions. Furthermore conventional Fenton process was able to achieve slightly over an 80% COD removal from a 'young' leachate, while for 'old' and 'mixed' leachates was close to a 70%. The main advantage showed by the photo-assisted Fenton treatment of landfill leachate was that it consumed 32 times less iron and produced 25 times less sludge volume yielding the same COD removal results than a conventional Fenton treatment.

  18. Cosmetic wastewater treatment using the Fenton, Photo-Fenton and H2O2/UV processes.

    Science.gov (United States)

    Marcinowski, Piotr P; Bogacki, Jan P; Naumczyk, Jeremi H

    2014-01-01

    Advanced Oxidation Processes (AOPs), such as the Fenton, photo-Fenton and H2O2/UV processes, have been investigated for the treatment of cosmetic wastewaters that were previously coagulated by FeCl3. The Photo-Fenton process at pH 3.0 with 1000/100 mg L(-1) H2O2/Fe(2+) was the most effective (74.0% Chemical Oxygen Demand (COD) removal). The Fenton process with 1200/500 mg L(-1) H2O2/Fe(2+) achieved a COD removal of 72.0%, and the H2O2/UV process achieved a COD removal of 47.0%. Spreading the H2O2 doses over time to obtain optimal conditions did not improve COD removal. The kinetics of the Fenton and photo-Fenton processes may be described by the following equation: d[COD]/dt = -a[COD] t(m) (t represents time and a and m are constants). The rate of COD removal by the H2O2/UV process may be described by a second-order reaction equation. Head Space, Solid-Phase MicroExtraction, Gas Chromatography and Mass Spectrometry (HS-SPME-GC-MS) were used to identify 48 substances in precoagulated wastewater. Among these substances, 26 were fragrances. Under optimal AOP conditions, over 99% of the identified substances were removed in 120 min.

  19. Efficient treatment of an electroplating wastewater containing heavy metal ions, cyanide, and organics by H2O2 oxidation followed by the anodic Fenton process.

    Science.gov (United States)

    Zhao, Xu; Wang, Haidong; Chen, Fayuan; Mao, Ran; Liu, Huijuan; Qu, Jiuhui

    2013-01-01

    A real electroplating wastewater, containing heavy metals, cyanide, and organic contaminants, was treated by electrocoagulation (EC), H2O2 oxidation, H2O2 pre-oxidation followed by EC, and the anodic Fenton process and the efficacy of the processes was compared. Concentration of cyanide, Cu, Ni, Zn, and Cr was largely decreased by EC within 5 min. When the reaction time was extended, removal of residual cyanide, Cu, and Ni was limited. In H2O2 oxidation, the concentration of cyanide decreased from initial 75 to 12 mg L(-1) in 30 min. The effluents from the H2O2 oxidation were further treated by EC or anodic Fenton. In EC, the concentration of total cyanide, Ni, and Cu decreased to below 0.3, 0.5, and 1.5 mg L(-1), respectively. Removal efficiency of chemical oxygen demand by EC was less than 20.0%. By contrast, there was 73.5% reduction by the anodic Fenton process with 5 mM H2O2 at 30 min; this can be attributed to the oxidation induced by hydroxyl radicals generated by the reaction of H2O2 with the electrogenerated Fe(2+). Meanwhile, residual cyanide, Cu, and Ni can also be efficiently removed. Transformation of organic components in various processes was analyzed using UV-visible and fluorescence excitation-emission spectra.

  20. Fenton Redox Chemistry : Arsenite Oxidation by Metallic Surfaces

    NARCIS (Netherlands)

    Borges Freitas, S.C.; Van Halem, D.; Badruzzaman, A.B.M.; Van der Meer, W.G.J.

    2014-01-01

    Pre-oxidation of As(III) is necessary in arsenic removal processes in order to increase its efficiency. Therefore, the Fenton Redox Chemistry is defined by catalytic activation of H2O2 and currently common used for its redox oxidative properties. In this study the effect of H2O2 production catalysed

  1. Comparison of Fenton and Fenton-like oxidation for the treatment of cosmetic wastewater.

    Science.gov (United States)

    Bautista, P; Casas, J A; Zazo, J A; Rodriguez, J J; Mohedano, A F

    2014-01-01

    The treatment of cosmetic wastewaters by Fenton (Fe²⁺/H₂O₂) and Fenton-like (Fe³⁺/H₂O₂) oxidation has been studied. From batch and continuous experiments it has been proved that both versions of the Fenton process lead to quite similar results in terms of chemical oxygen demand (COD) and total organic carbon reduction although the COD shows a slightly higher rate in the early stages of reaction. COD reductions of around 55% after 2 h reaction time and 75-80% with 4 h residence time were reached in batch and continuous experiments, respectively, conducted at pH around 3, ambient temperature (20 °C), with 200 mg/L of Fe dose and an initial H₂O₂/COD weight ratio corresponding to the theoretical stoichiometric value. Achieving the locally allowable limit of COD for industrial wastewater discharge into the municipal sewer system takes no more than 30 min reaction time under those conditions by both Fenton systems. However, the Fenton-like process, where iron is fed as Fe(3+), would be preferable for industrial applications since the ferric sludge resulting upon final neutralization of the effluent can be recycled to the process. A second-order kinetic equation with respect to COD fitted fairly well the experimental results at different temperatures, thus providing a simple practical tool for design purposes.

  2. Fenton and solar photo-Fenton processes for the removal of ...

    African Journals Online (AJOL)

    Fenton (H2O2/Fe2+/solar light) processes was investigated. A laboratory-scale reactor was designed to evaluate and select the optimal oxidation condition. The degradation rate is strongly dependent on pH, temperature, H2O2 dosing rate, ...

  3. Evaluation of Fenton Oxidation Process Coupled with Biological Treatment for the Removal of Reactive Black 5 from Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Pegah Bahmani

    2013-06-01

    Full Text Available Biodegradation of azo dyes is difficult due to their complex structures and low BOD to COD ratios. In the present study, the efficiency of using Fenton’s reagent (H2O2 + Fe2+ as a pretreatment process to enhance microbial transformation of reactive black 5 (RB5 in an aqueous system was evaluated. The RB5 with an initial concentration of 250 mg/L was decolorized up to 90% in 60 h by using a bacterial consortium. Fenton’s reagent at a Fe2+ concentration of 0.5 mM and H2O2 concentration of 2.9 mM (molar ratio, 1:5.8 was most effective for decolorization at pH = 3.0. The extent of RB5 removal by the combined Fenton–biotreatment was about 2 times higher than that of biotreatment alone. The production of some aromatic amines intermediates implied partial mineralization of the RB5 in Fenton treatment alone; in addition, decreasing of GC-MS peaks suggested that dearomatization occurred in Fenton-biological process. Fenton pretreatment seems to be a cost–effective option for the biotreatment of azo dyes, due mainly to the lower doses of chemicals, lower sludge generation, and saving of time. Our results demonstrated positive effects of inoculating bacterial consortium which was capable of dye biodegradation with a Fenton’s pretreatment step as well as the benefits of low time required for the biological process. In addition, the potential of field performance of Fenton-biological process because of using bacterial consortium is an other positive effect of it.

  4. Impacts of operating parameters on oxidation-reduction potential and pretreatment efficacy in the pretreatment of printing and dyeing wastewater by Fenton process

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Huifang, E-mail: whfkhl@sina.com [College of Environment, Jiangsu Key Laboratory of Industrial Water-Conservation and Emission Reduction, Nanjing University of Technology, Nanjing 210009 (China); Wang, Shihe [Department of Municipal Engineering, Southeast University, Nanjing 210096 (China)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer A real printing and dyeing wastewater was pretreated by Fenton process. Black-Right-Pointing-Pointer We investigated impacts of operating parameters on ORP and pretreatment efficacy. Black-Right-Pointing-Pointer Relationship among ORP, operating parameters and treatment efficacy was established. Black-Right-Pointing-Pointer Pretreatment efficacy was in proportion to the exponent of temperature reciprocal. Black-Right-Pointing-Pointer We investigated kinetics of color and COD removal and BOD{sub 5}/COD ratio in solution. - Abstract: An experiment was conducted in a batch reactor for a real printing and dyeing wastewater pretreatment using Fenton process in this study. The results showed that original pH, hydrogen peroxide concentration and ferrous sulfate concentration affected ORP value and pretreatment efficacy greatly. Under experimental conditions, the optimal original pH was 6.61, and the optimal hydrogen peroxide and ferrous sulfate concentrations were 1.50 and 0.75 g L{sup -1}, respectively. The relationship among ORP, original pH, hydrogen peroxide concentration, ferrous sulfate concentration, and color (COD or BOD{sub 5}/COD) was established, which would be instructive in on-line monitoring and control of Fenton process using ORP. In addition, the effects of wastewater temperature and oxidation time on pretreatment efficacy were also investigated. With an increase of temperature, color and COD removal efficiencies and BOD{sub 5}/COD ratio increased, and they were in proportion to the exponent of temperature reciprocal. Similarly, color and COD removal efficiencies increased with increasing oxidation time, and both color and COD removal obeyed the first-order kinetics. The BOD{sub 5}/COD ratio could be expressed by a second-degree polynomial with respect to oxidation time, and the best biodegradability of wastewater was present at the oxidation time of 6.10 h.

  5. Degradation of azo dyes by sequential Fenton's oxidation and aerobic biological treatment

    International Nuclear Information System (INIS)

    Tantak, Nilesh P.; Chaudhari, Sanjeev

    2006-01-01

    A two stage sequential Fenton's oxidation followed by aerobic biological treatment train was used to achieve decolorization and to enhance mineralization of azo dyes, viz. Reactive Black 5 (RB5), Reactive Blue 13 (RB13), and Acid Orange 7 (AO7). In the first stage, Fenton's oxidation process was used while in the second stage aerobic sequential batch reactors (SBRs) were used as biological process. Study was done to evaluate effect of pH on Fenton's oxidation process. Results reveal that pH 3 was optimum pH for achieving decolorization and dearomatization of dyes by Fenton's process. Degradation of dye was assessed by COD reduction and reduction in aromatic amines (naphthalene chromophores) which was measured by reduction in absorbance at 200 nm. More than 95% of color was removed with Fenton's oxidation process in all dyes. In overall treatment train 81.95, 85.57, and 77.83% of COD reduction was achieved in RB5, RB13, and AO7 dyes, respectively. In the Fenton's oxidation process 56, 24.5, and 80% reduction in naphthalene group was observed in RB5, RB13, and AO7, respectively, which further increased to 81.34, 68.73, and 92% after aerobic treatment. Fenton's oxidation process followed by aerobic SBRs treatment sequence seems to be viable method for achieving significant degradation of azo dye

  6. Impacts of operating parameters on oxidation-reduction potential and pretreatment efficacy in the pretreatment of printing and dyeing wastewater by Fenton process.

    Science.gov (United States)

    Wu, Huifang; Wang, Shihe

    2012-12-01

    An experiment was conducted in a batch reactor for a real printing and dyeing wastewater pretreatment using Fenton process in this study. The results showed that original pH, hydrogen peroxide concentration and ferrous sulfate concentration affected ORP value and pretreatment efficacy greatly. Under experimental conditions, the optimal original pH was 6.61, and the optimal hydrogen peroxide and ferrous sulfate concentrations were 1.50 and 0.75 gL(-1), respectively. The relationship among ORP, original pH, hydrogen peroxide concentration, ferrous sulfate concentration, and color (COD or BOD(5)/COD) was established, which would be instructive in on-line monitoring and control of Fenton process using ORP. In addition, the effects of wastewater temperature and oxidation time on pretreatment efficacy were also investigated. With an increase of temperature, color and COD removal efficiencies and BOD(5)/COD ratio increased, and they were in proportion to the exponent of temperature reciprocal. Similarly, color and COD removal efficiencies increased with increasing oxidation time, and both color and COD removal obeyed the first-order kinetics. The BOD(5)/COD ratio could be expressed by a second-degree polynomial with respect to oxidation time, and the best biodegradability of wastewater was present at the oxidation time of 6.10h. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Degradation of the beta-blocker propranolol by electrochemical advanced oxidation processes based on Fenton's reaction chemistry using a boron-doped diamond anode

    Energy Technology Data Exchange (ETDEWEB)

    Isarain-Chavez, Eloy; Rodriguez, Rosa Maria; Garrido, Jose Antonio; Arias, Conchita; Centellas, Francesc; Cabot, Pere Lluis [Laboratori d' Electroquimica dels Materials i del Medi Ambient, Departament de Quimica Fisica, Facultat de Quimica, Universitat de Barcelona, Marti i Franques 1-11, 08028 Barcelona (Spain); Brillas, Enric, E-mail: brillas@ub.ed [Laboratori d' Electroquimica dels Materials i del Medi Ambient, Departament de Quimica Fisica, Facultat de Quimica, Universitat de Barcelona, Marti i Franques 1-11, 08028 Barcelona (Spain)

    2010-12-15

    The electro-Fenton (EF) and photoelectro-Fenton (PEF) degradation of solutions of the beta-blocker propranolol hydrochloride with 0.5 mmol dm{sup -3} Fe{sup 2+} at pH 3.0 has been studied using a single cell with a boron-doped diamond (BDD) anode and an air diffusion cathode (ADE) for H{sub 2}O{sub 2} electrogeneration and a combined cell containing the above BDD/ADE pair coupled in parallel to a Pt/carbon felt (CF) cell. This naphthalene derivative can be mineralized by both methods with a BDD anode. Almost overall mineralization is attained for the PEF treatments, more rapidly with the combined system due to the generation of higher amounts of hydroxyl radical from Fenton's reaction by the continuous Fe{sup 2+} regeneration at the CF cathode, accelerating the oxidation of organics to Fe(III)-carboxylate complexes that are more quickly photolyzed by UVA light. The homologous EF processes are less potent giving partial mineralization. The effect of current density, pH and Fe{sup 2+} and drug concentrations on the oxidation power of PEF process in combined cell is examined. Propranolol decay follows a pseudo first-order reaction in most cases. Aromatic intermediates such as 1-naphthol and phthalic acid and generated carboxylic acids such as maleic, formic, oxalic and oxamic are detected and quantified by high-performance liquid chromatography. The chloride ions present in the starting solution are slowly oxidized at the BDD anode. In PEF treatments, all initial N of propranolol is completely transformed into inorganic ions, with predominance of NH{sub 4}{sup +} over NO{sub 3}{sup -} ion.

  8. Simultaneous Removal of Thallium and EDTA by Fenton Process

    Science.gov (United States)

    Xu, Ruibing; Huang, Xuexia; Li, Huosheng; Su, Minhua; Chen, Diyun

    2018-01-01

    The wastewater containing heavy metals and organic pollutants is widely discharged from industries. Because of the coexistence of heavy metals and organic pollutants, the treatment of such wastewater is very difficult. Fenton process is considered to be one of the most effective approaches for the degradation of organic pollutants in aqueous solution due to the strong oxidative ability of hydroxyl radical which generated from the Fenton process. Apart from this, heavy metals are able to be removed during Fenton process owning to the synergic effect of coagulation and precipitation. In this work, pollutants of thallium and EDTA were successfully removed via the Fenton process. A series of single-factor experiments were designed and performed to achieve an optimal reaction conditions for the removal of both thallium and EDTA. Results showed that the removal efficiencies of thallium and TOC could be as high as 96.54% and 70.42%, respectively. The outcomes from our study demonstrate that Fenton process is a promising method for the purification of wastewater containing thallium and EDTA.

  9. Application of Fenton oxidation to cosmetic wastewaters treatment.

    Science.gov (United States)

    Bautista, P; Mohedano, A F; Gilarranz, M A; Casas, J A; Rodriguez, J J

    2007-05-08

    The removal of organic matter (TOC and COD) from a cosmetic wastewater by Fenton oxidation treatment has been evaluated. The operating conditions (temperature as well as ferrous ion and hydrogen peroxide dosage) have been optimized. Working at an initial pH equal to 3.0, a Fe(2+) concentration of 200 mg/L and a H(2)O(2) concentration to COD initial weight ratio corresponding to the theoretical stoichiometric value (2.12), a TOC conversion higher than 45% at 25 degrees C and 60% at 50 degrees C was achieved. Application of the Fenton oxidation process allows to reach the COD regional limit for industrial wastewaters discharges to the municipal sewer system. A simple kinetic analysis based on TOC was carried out. A second-order equation describes well the overall kinetics of the process within a wide TOC conversion range covering up to the 80-90% of the maximum achievable conversion.

  10. Effect of the ultrasound-Fenton oxidation process with the addition of a chelating agent on the removal of petroleum-based contaminants from soil.

    Science.gov (United States)

    Li, Ying; Li, Fangmin; Li, Fanxiu; Yuan, Fuqian; Wei, Pingfang

    2015-12-01

    The effects of ultrasonic irradiation, the chelating agent modified Fenton reaction, and a combination of ultrasound and the Fenton method in removing petroleum contaminants from a soil were studied. The results showed that the contaminant removal rate of the Fenton treatment combined with an oxalic acid chelating agent was 55.6% higher than that without a chelating agent. The average removal rate of the contaminants using the ultrasound-Fenton treatment was 59.0% higher than that without ultrasonic treatment. A combination of ultrasound and an Fe(2+)/Fe(3+)-oxalate complex-modified Fenton reagent resulted in significantly higher removal rates of n-alkanes (C(n)H(2n+2), n Fenton method. The Fenton reaction and the ultrasound-Fenton treatment can unselectively remove multiple components of residual hydrocarbons and a number of benzene rings in polycyclic aromatic hydrocarbons. The chemistry of the heterocyclic compounds and the position and number of substituents can affect the degradation process.

  11. Degradation of the azo dye Acid Red 1 by anodic oxidation and indirect electrochemical processes based on Fenton's reaction chemistry. Relationship between decolorization, mineralization and products

    International Nuclear Information System (INIS)

    Florenza, Xavier; Solano, Aline Maria Sales; Centellas, Francesc; Martínez-Huitle, Carlos Alberto

    2014-01-01

    Highlights: • Degradation of Acid Red 1 by anodic oxidation, electro-Fenton and photoelectro-Fenton • Quicker and similar decolorization by electro-Fenton and photoelectro-Fenton due to oxidation with ● OH in the bulk • Almost total mineralization by photoelectro-Fenton with Pt or BDD due to fast photolysis of products by UVA light • Detection of 11 aromatic products, 15 hydroxylated compounds, 13 desulfonated derivatives and 7 carboxylic acids • Release of NH 4 + , NO 3 − and SO 4 2− ions, and generation of persistent N-products of low molecular mass - Abstract: Solutions of 236 mg dm −3 Acid Red 1 (AR1), an azo dye widely used in textile dying industries, at pH 3.0 have been comparatively treated by anodic oxidation with electrogenerated H 2 O 2 (AO-H 2 O 2 ), electro-Fenton (EF) and photoelectro-Fenton (PEF) at constant current density (j). Assays were performed with a stirred tank reactor equipped with a Pt or boron-doped diamond (BDD) anode and an air-diffusion cathode for H 2 O 2 generation from O 2 reduction. The main oxidizing agents were hydroxyl radicals produced at the anode from water oxidation in all methods and in the bulk from Fenton's reaction between generated H 2 O 2 and 0.5 mmol dm −3 Fe 2+ in EF and PEF. For each anode, higher oxidation power was found in the sequence AO-H 2 O 2 < EF < PEF. The oxidation ability of the BDD anode was always superior to that of Pt. Faster and similar decolorization efficiency was achieved in EF and PEF owing to the quicker destruction of aromatics with hydroxyl radicals produced in the bulk. The PEF process with BDD was the most potent method yielding almost total mineralization due to the additional rapid photolysis of recalcitrant intermediates like Fe(III)-carboxylate complexes under UVA irradiation. The increase in j always enhanced the decolorization and mineralization processes because of the greater production of hydroxyl radicals, but decreases the mineralization current efficiency

  12. Mature landfill leachate treatment by coagulation/flocculation combined with Fenton and solar photo-Fenton processes.

    Science.gov (United States)

    Amor, Carlos; De Torres-Socías, Estefanía; Peres, José A; Maldonado, Manuel I; Oller, Isabel; Malato, Sixto; Lucas, Marco S

    2015-04-09

    This work reports the treatment of a mature landfill leachate through the application of chemical-based treatment processes in order to achieve the discharge legal limits into natural water courses. Firstly, the effect of coagulation/flocculation with different chemicals was studied, evaluating the role of different initial pH and chemicals concentration. Afterwards, the efficiency of two different advanced oxidation processes for leachate remediation was assessed. Fenton and solar photo-Fenton processes were applied alone and in combination with a coagulation/flocculation pre-treatment. This physicochemical conditioning step, with 2 g L(-1) of FeCl3 · 6H2O at pH 5, allowed removing 63% of COD, 80% of turbidity and 74% of total polyphenols. Combining the coagulation/flocculation pre-treatment with Fenton reagent, it was possible to reach 89% of COD removal in 96 h. Moreover, coagulation/flocculation combined with solar photo-Fenton revealed higher DOC (75%) reductions than single solar photo-Fenton (54%). In the combined treatment (coagulation/flocculation and solar photo-Fenton), it was reached a DOC reduction of 50% after the chemical oxidation, with 110 kJ L(-1) of accumulated UV energy and a H2O2 consumption of 116 mM. Toxicity and biodegradability assays were performed to evaluate possible variations along the oxidation processes. After the combined treatment, the leachate under study presented non-toxicity but biodegradability increased. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Kinetics of Acid Orange 7 oxidation by using carbon fiber and reticulated vitreous carbon in an electro-Fenton process.

    Science.gov (United States)

    Ramírez-Pereda, Blenda; Álvarez-Gallegos, Alberto; Rangel-Peraza, Jesús Gabriel; Bustos-Terrones, Yaneth A

    2018-05-01

    In this study, a micro-scale parallel plate reactor was built to electrochemically generate hydrogen peroxide (H 2 O 2 ) and to develop the Fenton reaction in situ, for the treatment of toxic organic pollutants. Two types of carbon materials were compared and used as cathodes: unidirectional carbon fiber (CF) and reticulated vitreous carbon (RVC). As anode, a stainless steel mesh was used. The results of H 2 O 2 were experimentally compared by means of electrogeneration process. RVC cathode with dimensions of 2.5 × 1 × 5 cm (170 mA and variable voltage V = 2.0-2.7) and 180 min produced 5.3 mM H 2 O 2 , with an H 2 O 2 production efficiency of 54%. Unidirectional carbon fiber cathode produced 7.5 mM of H 2 O 2 (96% of H 2 O 2 production efficiency) when a voltage of 1.8 V was applied during 180 min to a total area of 480 cm 2 of this material. Acid Orange 7 (AO7) was degraded to a concentration of 0.16 mM during the first 40 min of the process, which represented 95% of the initial concentration. Electrolysis process removed nearly 100% of the AO7 using both cathodes at the end of these experiments (180 min). Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Kaolinite adsorption-regeneration system for dyestuff treatment by Fenton based processes.

    Science.gov (United States)

    Rosales, Emilio; Anasie, Delia; Pazos, Marta; Lazar, Iuliana; Sanromán, M Angeles

    2018-05-01

    The regeneration and reuse of adsorbents is a subject of interest nowadays in order to reduce the pollution and the wastes generated in the adsorption wastewater treatment. In this work, the regeneration of the spent kaolinite by different advanced oxidation processes (Fenton, electro-Fenton and electrokinetic-Fenton) was evaluated. Initially, it was confirmed the ability of a low cost clayey material, kaolinite, for the adsorption of model dye such as Rhodamine B showing Freundlich isotherm fitting. Then, the regeneration and consequent degradation of the pollutant in the adsorbent by Fenton based processes was carried out. The role of different parameters affecting the regeneration process (H 2 O 2 :Fe 2+ ratio, liquid:solid ratio) were evaluated. Working at 100:1 H 2 O 2 :Fe 2+ ratio and 30min near complete dye removal (around 97%) from kaolinite was obtained by Fenton treatment. After that, a two-stage treatment for adsorption-regeneration was evaluated during five treatment cycles demonstrating its viability for regeneration of the adsorbent through dye degradation. Based on the successful application of Fenton technique, the improvement of the treatment by electro-Fenton and electrokinetic-Fenton were studied for different solid:liquid ratios achieving satisfactory regeneration values. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Treatment of real paracetamol wastewater by fenton process

    Directory of Open Access Journals (Sweden)

    Dalgic Gamze

    2017-01-01

    Full Text Available The study investigated the pretreatment of real paracetamol (PCT wastewater of a pharmaceutical industry by Fenton process. At the best experimental conditions (COD/H2O2 = 1/1, Fe+2/H2O2 = 1/70, settling method:centrifuging, pH 6 at settling step, 92.7, 92.7, 95.5, 99.1, 99.9 and 99.4% of chemical oxygen demand (COD, total organic carbon (TOC, 5-day biological oxygen demand (BOD5, PCT, para-amino phenol (PAP and aniline were removed, respectively. Changes in the concentrations of these parameters were also investigated for both oxidation and settling steps of Fenton process. It was found that COD and TOC were removed at the settling step (precipitation whereas PCT, PAP and aniline were removed at the oxidation step. Mass balance calculations were also studied to show the mass distributions of COD in different phases (gas + foam, effluent and sludge. Fenton process was found as an effective method for the pretreatment of real PCT wastewater for discharging in a determined collective treatment plant.

  16. Iron crystallization in a fluidized-bed Fenton process.

    Science.gov (United States)

    Boonrattanakij, Nonglak; Lu, Ming-Chun; Anotai, Jin

    2011-05-01

    The mechanisms of iron precipitation and crystallization in a fluidized-bed reactor were investigated. Within the typical Fenton's reagent dosage and pH range, ferric ions as a product from ferrous ion oxidation would be supersaturated and would subsequently precipitate out in the form of ferric hydroxide after the initiation of the Fenton reaction. These precipitates would simultaneously crystallize onto solid particles in a fluidized-bed Fenton reactor if the precipitation proceeded toward heterogeneous nucleation. The heterogeneous crystallization rate was controlled by the fluidized material type and the aging/ripening period of the crystallites. Iron crystallization onto the construction sand was faster than onto SiO(2), although the iron removal efficiencies at 180 min, which was principally controlled by iron hydroxide solubility, were comparable. To achieve a high iron removal rate, fluidized materials have to be present at the beginning of the Fenton reaction. Organic intermediates that can form ferro-complexes, particularly volatile fatty acids, can significantly increase ferric ion solubility, hence reducing the crystallization performance. Therefore, the fluidized-bed Fenton process will achieve exceptional performance with respect to both organic pollutant removal and iron removal if it is operated with the goal of complete mineralization. Crystallized iron on the fluidized media could slightly retard the successive crystallization rate; thus, it is necessary to continuously replace a portion of the iron-coated bed with fresh media to maintain iron removal performance. The iron-coated construction sand also had a catalytic property, though was less than those of commercial goethite. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Degradation alternatives for a commercial fungicide in water: biological, photo-Fenton, and coupled biological photo-Fenton processes.

    Science.gov (United States)

    López-Loveira, Elsa; Ariganello, Federico; Medina, María Sara; Centrón, Daniela; Candal, Roberto; Curutchet, Gustavo

    2017-11-01

    Imazalil (IMZ) is a widely used fungicide for the post-harvest treatment of citrus, classified as "likely to be carcinogenic in humans" for EPA, that can be only partially removed by conventional biological treatment. Consequently, specific or combined processes should be applied to prevent its release to the environment. Biological treatment with adapted microorganism consortium, photo-Fenton, and coupled biological photo-Fenton processes were tested as alternatives for the purification of water containing high concentration of the fungicide and the coadjutants present in the commercial formulation. IMZ-resistant consortium with the capacity to degrade IMZ in the presence of a C-rich co-substrate was isolated from sludge coming from a fruit packaging company wastewater treatment plant. This consortium was adapted to resist and degrade the organics present in photo-Fenton-oxidized IMZ water solution. Bacteria colonies from the consortia were isolated and identified. The effect of H 2 O 2 initial concentration and dosage on IMZ degradation rate, average oxidation state (AOS), organic acid concentration, oxidation, and mineralization percentage after photo-Fenton process was determined. The application of biological treatment to the oxidized solutions notably decreased the total organic carbon (TOC) in solution. The effect of the oxidation degree, limited by H 2 O 2 concentration and dosage, on the percentage of mineralization obtained after the biological treatment was determined and explained in terms of changes in AOS. The concentration of H 2 O 2 necessary to eliminate IMZ by photo-Fenton and to reduce TOC and chemical oxygen demand (COD) by biological treatment, in order to allow the release of the effluents to rivers with different flows, was estimated.

  18. Effects of reaction conditions on nuclear laundry water treatment in Fenton process

    International Nuclear Information System (INIS)

    Vilve, Miia; Hirvonen, Arja; Sillanpaeae, Mika

    2009-01-01

    This study presents the efficiency of Fenton process in the degradation of organic compounds of nuclear laundry water. The influence of Fe 2+ and hydrogen peroxide ratio, hydrogen peroxide dose, pH and treatment time were investigated. The degradation of non-ionic surfactant and other organic compounds was analysed as COD, TOC and molecular weight distribution (MWD). The most cost-effective degradation conditions were at H 2 O 2 /Fe 2+ stoichiometric molar ratio of 2 with 5 min mixing and H 2 O 2 dose of 1000 mg l -1 . With the initial pH of 6, the reductions of COD and TOC were 85% and 69%, respectively. However, the removal of the organic compounds was mainly carried out by Fenton-based Fe 3+ coagulation rather than Fenton oxidation. Fenton process proved to be much more efficient than previously performed ozone-based oxidation processes.

  19. Sono-photo-Fenton oxidation of bisphenol-A over a LaFeO3 perovskite catalyst.

    Science.gov (United States)

    Dükkancı, Meral

    2018-01-01

    In this study, oxidation of bisphenol-A (IUPAC name - 2,2-(4,4-dihydroxyphenyl, BPA), which is an endocrine disrupting phenolic compound used in the polycarbonate plastic and epoxy resin industry, was investigated using sono-photo-Fenton process under visible light irradiation in the presence of an iron containing perovskite catalyst, LaFeO 3 . The catalyst prepared by sol-gel method, calcined at 500°C showed a catalytic activity in BPA oxidation using sono-photo-Fenton process with a degradation degree and a chemical oxygen demand (COD) reduction of 21.8% and 11.2%, respectively. Degradation of BPA was studied by using individual and combined advanced oxidation techniques including sonication, heterogeneous Fenton reaction and photo oxidation over this catalyst to understand the effect of each process on degradation of BPA. It was seen, the role of sonication was very important in hybrid sono-photo-Fenton process due to the pyrolysis and sonoluminescence effects caused by ultrasonic irradiation. The prepared LaFeO 3 perovskite catalyst was a good sonocatalyst rather than a photocatalyst. Sonication was not only the effective process to degrade BPA but also it was the cost effective process in terms of energy consumption. The studies show that the energy consumption is lower in the sono-Fenton process than those in the photo-Fenton and sono-photo- Fenton processes. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. For the Fenton process in a sequential downflow and upflow system to treat textile dyeing wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Bae, W.K.; Ko, G.B.; Cho, S.J. [Dept. of Civil and Environmental Engineering, Hanyang Univ., Kyounggi (Korea); Lee, S.H. [Dept. of Environmental Engineering, Sangmyung Univ., Cheonan (Korea)

    2003-07-01

    Wastewater from textile dyeing industry is characterized by high temperature, pH, pollution loading such as color and COD which are containing refractory, toxic and high molecular weight compounds. It is therefore, presumed to be very resistant to microbial degradation. Textile dyeing wastewater is therefore, presumed to be very resistant to microbial degradation. Combined processes are usually applied, which are chemical oxidation and biological process for textile dyeing wastewater in order to satisfy water quality standards. Fenton process as advanced oxidation process is well known as effective process for the removal of color and recalcitrant organics. However, the exactly predominant reaction mechanisms during Fenton process are not well explained among coagulation, oxidation and sedimentation so far. This research attempts to evaluate the predominant reaction with comparable results of ferric coagulation and oxidation for the Fenton process. (orig.)

  1. Application of the photo-fenton process to the mineralization of phthalic anhydride in aqueous medium

    International Nuclear Information System (INIS)

    Trabelsi Souissi, Souhaila; Oturan, N.; Oturan, M. A; Bellakhal, N.

    2009-01-01

    A photochemical method for the oxidation of persistent organic pollutants (POPs) present in liquid effluents of plastic industry is described. This method, called p hoto-Fenton , involves the generation of hydroxyl radicals by coupling the Fenton reaction and photochemistry, .OH radicals thus formed react rapidly with organic pollutants leading to their oxidation until their total mineralization. In this study, we applied the photo-Fenton process for the removal of phthalic anhydride (plasticizer). In this way, an optimization of experimental parameters (namely the ratio R = [H 2 O 2 ]/[Fe 3+ ] and Fe 3+ initial concentration) was performed. Under optimal conditions, the kinetic of mineralization of phthalic anhydride by .OH has been studied. All results confirm the efficiency of photo-Fenton process for the decontamination of liquid effluents loaded with plasticizers.

  2. Stabilization of hydrogen peroxide using tartaric acids in Fenton and fenton-like oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Hyung Suk; Kim, Jeong-Jin; Kim, Young-Hun [Andong National University, Andong (Korea, Republic of)

    2016-03-15

    The stabilization of hydrogen peroxide is a key factor in the efficiency of a Fenton reaction. The stability of hydrogen peroxide was evaluated in a Fenton reaction and Fenton-like reactions in the presence of tartaric acid as a stabilizer. The interactions between ferrous or ferric iron and tartaric acid were observed through spectroscopic monitoring at variable pH around pKa{sub 1} and pKa{sub 2} of the stabilizer. Ferric iron had a strong interaction with the stabilizer, and the strong interaction was dominant above pKa{sub 2}. At a low pH, below pKa{sub 1}, the stabilizing effect was at its maximum and the prolonged life-time of hydrogen peroxide gave a higher efficiency to the oxidative degradation of nitrobenzene. In Fenton-like reactions with hematite, the acidic conditions caused dissolution of iron from an iron oxide, and an increase in iron species was the result. Tartaric acid showed a stabilizing effect on hydrogen peroxide in the Fentonlike system. The stabilization by tartaric acid might be due to an inhibition of catalytic activity of dissolved iron, and the stabilization strongly depends on the ionization state of the stabilizer.

  3. Stabilization of hydrogen peroxide using tartaric acids in Fenton and fenton-like oxidation

    International Nuclear Information System (INIS)

    Oh, Hyung Suk; Kim, Jeong-Jin; Kim, Young-Hun

    2016-01-01

    The stabilization of hydrogen peroxide is a key factor in the efficiency of a Fenton reaction. The stability of hydrogen peroxide was evaluated in a Fenton reaction and Fenton-like reactions in the presence of tartaric acid as a stabilizer. The interactions between ferrous or ferric iron and tartaric acid were observed through spectroscopic monitoring at variable pH around pKa 1 and pKa 2 of the stabilizer. Ferric iron had a strong interaction with the stabilizer, and the strong interaction was dominant above pKa 2 . At a low pH, below pKa 1 , the stabilizing effect was at its maximum and the prolonged life-time of hydrogen peroxide gave a higher efficiency to the oxidative degradation of nitrobenzene. In Fenton-like reactions with hematite, the acidic conditions caused dissolution of iron from an iron oxide, and an increase in iron species was the result. Tartaric acid showed a stabilizing effect on hydrogen peroxide in the Fentonlike system. The stabilization by tartaric acid might be due to an inhibition of catalytic activity of dissolved iron, and the stabilization strongly depends on the ionization state of the stabilizer.

  4. IN-SITU FENTON OXIDATION: A CRITICAL ANALYSIS

    Science.gov (United States)

    In-situ Fenton oxidation (ISFO) is a rapidly emerging technology which involves the injection of hydrogen peroxide (H2O2) and other chemical reagents into the subsurface for the purpose of oxidizing and transforming contaminants. ISFO is being applied at an increasing number of ...

  5. Performance of Fluidized bed Fenton process in Degrading Acid Blue 113

    Science.gov (United States)

    Bello, M. M.; Raman, A. A.

    2017-06-01

    The performance of a fluidized bed Fenton process in degrading Acid Blue 113 (AB 113) was investigated. Fluidized bed Fenton process is a modification of conventional Fenton oxidation, aimed at reducing sludge generation and improving process performance. Response surface methodology was used to study the effects of operational parameter on the color removal from the dye. Dimensionless factors, Dye/Fe2+, H2O2/Fe2+ and pH were used as the independent variables in Box-Behnken Design (BDD). Reduced quadratic model was developed to predict the color removal. The process could remove up to 99 % of the initial color. The most significant factor for color removal was found to be Dye/Fe2+, followed by H2O2/Fe2+. Unlike conventional Fenton, the initial pH of the solution does not have a significant effect on the color removal.

  6. Treatment of textile effluent by chemical (Fenton's Reagent) and biological (sequencing batch reactor) oxidation

    International Nuclear Information System (INIS)

    Rodrigues, Carmen S.D.; Madeira, Luis M.; Boaventura, Rui A.R.

    2009-01-01

    The removal of organic compounds and colour from a synthetic effluent simulating a cotton dyeing wastewater was evaluated by using a combined process of Fenton's Reagent oxidation and biological degradation in a sequencing batch reactor (SBR). The experimental design methodology was first applied to the chemical oxidation process in order to determine the values of temperature, ferrous ion concentration and hydrogen peroxide concentration that maximize dissolved organic carbon (DOC) and colour removals and increase the effluent's biodegradability. Additional studies on the biological oxidation (SBR) of the raw and previously submitted to Fenton's oxidation effluent had been performed during 15 cycles (i.e., up to steady-state conditions), each one with the duration of 11.5 h; Fenton's oxidation was performed either in conditions that maximize the colour removal or the increase in the biodegradability. The obtained results allowed concluding that the combination of the two treatment processes provides much better removals of DOC, BOD 5 and colour than the biological or chemical treatment alone. Moreover, the removal of organic matter in the integrated process is particularly effective when Fenton's pre-oxidation is carried out under conditions that promote the maximum increase in wastewater biodegradability.

  7. Electrochemical treatment of Acid Red 1 by electro-Fenton and photoelectro-Fenton processes

    Directory of Open Access Journals (Sweden)

    Camilo González-Vargas

    2014-12-01

    Full Text Available Small volumes (100 mL of acidic aqueous solutions with 30-200 mg L-1 TOC of the toxic azo dye Acid Red 1 (AR1 have been comparatively treated by various electrochemical advanced oxidation processes (EAOPs. The electrolytic system consisted of a BDD anode able to produce ·OH and an air-diffusion cathode that generated H2O2, which subsequently reacted with added Fe2+ to yield additional ·OH from Fenton’s reaction. Under optimized conditions (i.e., 1.0 mM Fe2+, 60 mA cm-2, pH 3.0, 35 ºC, the analysis of the initial rates for decolourization and AR1 decay assuming a pseudo-first-order kinetics revealed a much higher rate constant for photoelectro-Fenton (PEF, ~ 2.7x10-3 s-1 compared to electro-Fenton (EF, ~ 0.6x10-3 s-1. Mineralization after 180 min was also greater in the former treatment (90 % vs 63 %. The use of UV radiation in PEF contributed to Fe(III photoreduction as well as to photodecarboxylation of refractory intermediates, yielding a mineralization current efficiency as high as 85% during the treatment of solutions of 200 mg L-1 TOC. Primary reaction intermediates included three aromatic derivatives with the initial naphthalenic structure and four molecules only featuring benzenic rings, which were totally mineralized in PEF. 

  8. Photonic efficiency of the photodegradation of paracetamol in water by the photo-Fenton process.

    Science.gov (United States)

    Yamal-Turbay, E; Ortega, E; Conte, L O; Graells, M; Mansilla, H D; Alfano, O M; Pérez-Moya, M

    2015-01-01

    An experimental study of the homogeneous Fenton and photo-Fenton degradation of 4-amidophenol (paracetamol, PCT) is presented. For all the operation conditions evaluated, PCT degradation is efficiently attained by both Fenton and photo-Fenton processes. Also, photonic efficiencies of PCT degradation and mineralization are determined under different experimental conditions, characterizing the influence of hydrogen peroxide (H2O2) and Fe(II) on both contaminant degradation and sample mineralization. The maximum photonic degradation efficiencies for 5 and 10 mg L(-1) Fe(II) were 3.9 (H2O2 = 189 mg L(-1)) and 5 (H2O2 = 378 mg L(-1)), respectively. For higher concentrations of oxidant, H2O2 acts as a "scavenger" radical, competing in pollutant degradation and reducing the reaction rate. Moreover, in order to quantify the consumption of the oxidizing agent, the specific consumption of the hydrogen peroxide was also evaluated. For all operating conditions of both hydrogen peroxide and Fe(II) concentration, the consumption values obtained for Fenton process were always higher than the corresponding values observed for photo-Fenton. This implies a less efficient use of the oxidizing agent for dark conditions.

  9. Fenton-Like Oxidation of Malachite Green Solutions: Kinetic and Thermodynamic Study

    Directory of Open Access Journals (Sweden)

    Saeedeh Hashemian

    2013-01-01

    Full Text Available Oxidation by Fenton-like (Fe3+/H2O2 reactions is proven to be an economically feasible process for destruction of a variety of hazardous pollutants in wastewater. In this study, the degradation and mineralization of malachite green dye are reported using Fenton-like reaction. The effects of different parameters like pH of the solution, the initial concentrations of Fe3+, H2O2, and dye, temperature, and added electrolytes (Cl− and on the oxidation of the dye were investigated. Optimized condition was determined. The efficiency of 95.5% degradation of MAG after 15 minutes of reaction at pH 3 was obtained. TOC removal indicates partial and insignificant mineralization of malachite green dye. The results of experiments showed that degradation of malachite green dye in Fenton-like oxidation process can be described with a pseudo-second-order kinetic model. The thermodynamic constants of the Fenton oxidation process were evaluated. The results implied that the oxidation process was feasible, spontaneous, and endothermic. The results will be useful for designing the treatment systems of various dye-containing wastewaters.

  10. CONTAMINANT ADSORPTION AND OXIDATION VIA FENTON REACTION

    Science.gov (United States)

    A ground water treatment process is proposed involving two cgemical processes: adsorption and oxidation. Adsorption of an organic compound onto granulated activated carbon (GAC) containing iron conveniently results in immobilizing and concentrating contaminants from the ground w...

  11. Degradation of flumequine by the Fenton and photo-Fenton processes: Evaluation of residual antimicrobial activity

    International Nuclear Information System (INIS)

    Rodrigues-Silva, Caio; Maniero, Milena Guedes; Rath, Susanne; Guimarães, José Roberto

    2013-01-01

    Flumequine is a broad-spectrum antimicrobial agent of the quinolone class, and it is widely used as a veterinary drug in food-producing animals. The presence of flumequine in the environment may contribute to the development of drug resistant bacterial strains. In this study, water samples fortified with flumequine (500 μg L −1 ) were degraded using the Fenton and photo-Fenton processes. The maximum degradation efficiency for flumequine by the Fenton process was approximately 40% (0.5 mmol L −1 Fe(II), 2.0 mmol L −1 H 2 O 2 and 15 min). By applying UV radiation (photo-Fenton process), the efficiency reached more than 94% in 60 min when 0.25 mmol L −1 Fe(II) and 10.0 mmol L −1 H 2 O 2 were used. Under these conditions, the Fenton process was able to reduce the biological activity, whereas the photo-Fenton process eliminated almost all of the antimicrobial activity because it was not detected. Four byproducts with an m/z of 244, 238, 220 and 202 were identified by mass spectrometry, and a degradation pathway for flumequine was proposed. The byproducts were derived from decarboxylation and defluorination reactions and from modifications in the alkylamino chain of the fluoroquinolone. - Highlights: ► Photo-Fenton process achieved the maximum performance, degrading 94% of flumequine. ► As the flumequine concentration decreased, antimicrobial activity also decreased. ► Four byproducts with m/z of 244, 238, 220 and 202 were identified. ► A degradation pathway for flumequine was proposed

  12. Degradation of flumequine by the Fenton and photo-Fenton processes: Evaluation of residual antimicrobial activity

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues-Silva, Caio; Maniero, Milena Guedes [School of Civil Engineering, Architecture and Urbanism, University of Campinas — UNICAMP, P.O. Box 6021, CEP 13083-852, Campinas, SP (Brazil); Rath, Susanne [Chemistry Institute, University of Campinas — UNICAMP, P.O. Box 6154, CEP 13084-971, Campinas, SP (Brazil); Guimarães, José Roberto, E-mail: jorober@fec.unicamp.br [School of Civil Engineering, Architecture and Urbanism, University of Campinas — UNICAMP, P.O. Box 6021, CEP 13083-852, Campinas, SP (Brazil)

    2013-02-15

    Flumequine is a broad-spectrum antimicrobial agent of the quinolone class, and it is widely used as a veterinary drug in food-producing animals. The presence of flumequine in the environment may contribute to the development of drug resistant bacterial strains. In this study, water samples fortified with flumequine (500 μg L{sup −1}) were degraded using the Fenton and photo-Fenton processes. The maximum degradation efficiency for flumequine by the Fenton process was approximately 40% (0.5 mmol L{sup −1} Fe(II), 2.0 mmol L{sup −1} H{sub 2}O{sub 2} and 15 min). By applying UV radiation (photo-Fenton process), the efficiency reached more than 94% in 60 min when 0.25 mmol L{sup −1} Fe(II) and 10.0 mmol L{sup −1} H{sub 2}O{sub 2} were used. Under these conditions, the Fenton process was able to reduce the biological activity, whereas the photo-Fenton process eliminated almost all of the antimicrobial activity because it was not detected. Four byproducts with an m/z of 244, 238, 220 and 202 were identified by mass spectrometry, and a degradation pathway for flumequine was proposed. The byproducts were derived from decarboxylation and defluorination reactions and from modifications in the alkylamino chain of the fluoroquinolone. - Highlights: ► Photo-Fenton process achieved the maximum performance, degrading 94% of flumequine. ► As the flumequine concentration decreased, antimicrobial activity also decreased. ► Four byproducts with m/z of 244, 238, 220 and 202 were identified. ► A degradation pathway for flumequine was proposed.

  13. Evaluation of Fenton Process in Removal of Direct Red 81

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Baghapour

    2016-01-01

    Full Text Available Background: Dyes are visible materials and are considered as one of the hazardous components that make up the industrial waste. Dye compounds in natural water, even in very low concentrations, will lead to environmental problems. Azo dyes are compounds with one or more –N=N– groups and are used in textile industry. Because of its low price, solubility, and stability, azo dyes are widely used in the textile industry. Direct Red 81 (DR81 is one of the azo dyes, which is removed from bodies of water, using various methods. This study aimed to assess DR81 dye removal by Fenton oxidation and the effects of various parameters on this process. Methods: Decolorization tests by Fenton oxidation were performed at dye concentrations of 50, 500, 100 and 1000 mg/L; hydrogen peroxide concentrations of 0, 10, 30, 60 and 120 mg/L; iron (II sulfate heptahydrate concentrations of 0, 3, 5, 20 and 50 mg/L; and pH levels of 3, 5, 7 and 10 for durations of 5, 10, 20, 30, 60 and 180 minutes. Results: The optimal condition occurred at a dye concentration of 20 mg/L, hydrogen peroxide concentration of 120 mg/L, bivalent iron concentration of 100 mg/L, pH of 3, and duration of 30 minutes. Under such conditions, the maximum dye removal rate was 88.98%. Conclusion: The results showed that DR81 could be decomposed and removed by Fenton oxidation. In addition, the removal of Direct Red 81 (DR81 depends on several factors such as dye concentration, reaction time, concentrations of hydrogen peroxide and iron, and pH

  14. Comparison of Fenton and sono-Fenton bisphenol A degradation

    International Nuclear Information System (INIS)

    Ioan, Iordache; Wilson, Steven; Lundanes, Elsa; Neculai, Aelenei

    2007-01-01

    Degradation of bisphenol A (BPA) was carried out with the Fenton reagent with and without additional sonochemical treatment. The Fenton and the sono-Fenton decomposition of BPA showed that ultrasound irradiation of wastewater improved the wet oxidation process of 25 mg l -1 BPA solutions. The sonochemical degradation of BPA was monitored using UV absorption and large volume injection packed capillary LC measurements

  15. Optimization of radiolytic degradation of sulfadiazine by combining Fenton and gamma irradiation processes

    International Nuclear Information System (INIS)

    Rivas-Ortiz, Iram Barbaro; Cruz-Gonzalez, German; Manduca-Artiles, Michel; Jauregui-Haza, U.J.

    2017-01-01

    Gamma radiation (GR) is a promising technique, among known advanced oxidation processes, degrading water contaminants. Nevertheless, few authors report the degradation of sulfonamides by GR, and limited information exists concerning the use of GR in the case of sulfadiazine (SDZ). The objectives of this work are (1) evaluating GR as an alternative method for treating wastewater contaminated with SDZ and examinating the intensification of GR with oxidants (H 2 O 2 or Fenton reagent). GR was performed with a high-activity 60 Co source. The gamma radiation/Fenton process gave the best result, leading to total SDZ removal and high (74.13%) pollutant mineralization. (author)

  16. Photo-assisted Fenton type processes for the degradation of phenol: A kinetic study

    International Nuclear Information System (INIS)

    Kusic, Hrvoje; Koprivanac, Natalija; Bozic, Ana Loncaric; Selanec, Iva

    2006-01-01

    In this study the application of advanced oxidation processes (AOPs), dark Fenton and photo-assisted Fenton type processes; Fe 2+ /H 2 O 2 , Fe 3+ /H 2 O 2 , Fe 0 /H 2 O 2 , UV/Fe 2+ /H 2 O 2 , UV/Fe 3+ /H 2 O 2 and UV/Fe 0 /H 2 O 2 , for degradation of phenol as a model organic pollutant in the wastewater was investigated. A detail kinetic modeling which describes the degradation of phenol was performed. Mathematical models which predict phenol decomposition and formation of primary oxidation by-products: catechol, hydroquinone and benzoquinone, by applied processes were developed. The study also consist the modeling of mineralization kinetic of the phenol solution by applied AOPs. This part, besides well known reactions of Fenton and photo-Fenton chemistry, involves additional reactions which describe removal of iron from catalytic cycle through formation of ferric complexes and its regeneration induced by UV radiation. Phenol decomposition kinetic was monitored by HPLC analysis and total organic carbon content measurements (TOC). Complete phenol removal was obtained by all applied processes. Residual TOC by applied Fenton type processes ranged between 60.2 and 44.7%, while the efficiency of those processes was significantly enhanced in the presence of UV light, where residual TOC ranged between 15.2 and 2.4%

  17. Use of Fenton oxidation to improve the biodegradability of a pharmaceutical wastewater

    International Nuclear Information System (INIS)

    Tekin, Huseyin; Bilkay, Okan; Ataberk, Selale S.; Balta, Tolga H.; Ceribasi, I. Haluk; Sanin, F. Dilek; Dilek, Filiz B.; Yetis, Ulku

    2006-01-01

    The applicability of Fenton's oxidation to improve the biodegradability of a pharmaceutical wastewater to be treated biologically was investigated. The wastewater was originated from a factory producing a variety of pharmaceutical chemicals. Treatability studies were conducted under laboratory conditions with all chemicals (having COD varying from 900 to 7000 mg/L) produced in the factory in order to determine the operational conditions to utilize in the full-scale treatment plant. Optimum pH was determined as 3.5 and 7.0 for the first (oxidation) and second stage (coagulation) of the Fenton process, respectively. For all chemicals, COD removal efficiency was highest when the molar ratio of H 2 O 2 /Fe 2+ was 150-250. At H 2 O 2 /Fe 2+ ratio of 155, 0.3 M H 2 O 2 and 0.002 M Fe 2+ , provided 45-65% COD removal. The wastewater treatment plant that employs Fenton oxidation followed by aerobic degradation in sequencing batch reactors (SBR), built after these treatability studies provided an overall COD removal efficiency of 98%, and compliance with the discharge limits. The efficiency of the Fenton's oxidation was around 45-50% and the efficiency in the SBR system which has two reactors each having a volume of 8 m 3 and operated with a total cycle time of 1 day, was around 98%, regarding the COD removal

  18. Degradation of malachite green in aqueous solution by Fenton process.

    Science.gov (United States)

    Hameed, B H; Lee, T W

    2009-05-30

    In this study, advanced oxidation process utilizing Fenton's reagent was investigated for degradation of malachite green (MG). The effects of different reaction parameters such as the initial MG concentration, initial pH, the initial hydrogen peroxide concentration, the initial ferrous concentration and the reaction temperature on the oxidative degradation of MG have been investigated. The optimal reacting conditions were experimentally found to be pH 3.40, initial hydrogen peroxide concentration=0.50mM and initial ferrous concentration=0.10mM for initial MG concentration of 20mg/L at 30 degrees C. Under optimal conditions, 99.25% degradation efficiency of dye in aqueous solution was achieved after 60 min of reaction.

  19. Comparison in decoloration efficiency among radiation, ultraviolet ray and Fenton oxidation treatment for aqueous solution of dyes

    International Nuclear Information System (INIS)

    Shimokawa, Toshishige; Sawai, Takeshi

    1984-01-01

    To establish the methods of oxidation and decomposition treatment for dyeing waste water, the processes by radiation, ultraviolet ray and Fenton oxidation were examined comparatively for the decoloration efficiency. The dyes tested were commercially available reactive dyes, RBO-3R, DBR-BB, MBY-6GS and RBB-R. In the radiation process, the dye solution was irradiated with gamma ray of cobalt-60 while blowing air through it. Radiation process and Fenton oxidation were excellent for decoloration. Ultraviolet ray was low in the treatment efficiency, so it is not practical. In the radiation process, the addition of a reagent and the adjustment of pH are not required unlike the case of the Fenton oxidation process. Its continuous operation is also possible, so it is a highly practical means. (Mori, K.)

  20. Personal Review: Progress and prospect in electro-Fenton process for wastewater treatment

    Institute of Scientific and Technical Information of China (English)

    JIANG Cheng-chun; ZHANG Jia-fa

    2007-01-01

    As a novel advanced oxidation process (AOP), electro-Fenton process is powerful for degrading most organic compounds including toxic and non-biodegradable ones, and so has attracted great attention. This paper reviews this process in detail including the mechanism, electrolytic bath, electrode materials, aerations and operation parameters. The application of electro-Fenton method in wastewater treatment is evaluated and summarized. Future work in this field is suggested, and three main directions of new electrode exploitation, development of assisted technologies and mechanistic study should be strengthened.

  1. Electro-Fenton oxidation of reverse osmosis concentrate from sanitary landfill leachate: Evaluation of operational parameters.

    Science.gov (United States)

    Fernandes, Annabel; Labiadh, Lazhar; Ciríaco, Lurdes; Pacheco, Maria José; Gadri, Abdellatif; Ammar, Salah; Lopes, Ana

    2017-10-01

    The electro-Fenton oxidation of a concentrate from reverse osmosis of a sanitary landfill leachate, with an initial chemical oxygen demand (COD) of 42 g L -1 , was carried out using a carbon-felt cathode and a boron doped diamond anode. The influence of the applied current intensity, initial pH and dissolved iron initial concentration on the electro-Fenton process was assessed. For the experimental conditions used, results showed that the initial pH is the parameter that more strongly influences the current efficiency of the electro-Fenton process, being this influence more pronounced on the oxidation rate than on the mineralization rate of the organic matter. The increase in iron initial concentration was found to be detrimental, since the natural amount of iron present in the effluent, 73 mg L -1 of total iron and 61 mg L -1 of dissolved iron, was sufficient to ensure the electro-Fenton process at the applied intensities - 0.2-1.4 A. For the more favourable conditions studied, initial pH of 3 and natural iron concentration, it was found an increase in the organic load and nitrogen removals with the applied current intensity. For the highest current intensity applied, a COD removal of 16.7 g L -1 was achieved after 8-h experiments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Sequential Combination of Electro-Fenton and Electrochemical Chlorination Processes for the Treatment of Anaerobically-Digested Food Wastewater.

    Science.gov (United States)

    Shin, Yong-Uk; Yoo, Ha-Young; Kim, Seonghun; Chung, Kyung-Mi; Park, Yong-Gyun; Hwang, Kwang-Hyun; Hong, Seok Won; Park, Hyunwoong; Cho, Kangwoo; Lee, Jaesang

    2017-09-19

    A two-stage sequential electro-Fenton (E-Fenton) oxidation followed by electrochemical chlorination (EC) was demonstrated to concomitantly treat high concentrations of organic carbon and ammonium nitrogen (NH 4 + -N) in real anaerobically digested food wastewater (ADFW). The anodic Fenton process caused the rapid mineralization of phenol as a model substrate through the production of hydroxyl radical as the main oxidant. The electrochemical oxidation of NH 4 + by a dimensionally stable anode (DSA) resulted in temporal concentration profiles of combined and free chlorine species that were analogous to those during the conventional breakpoint chlorination of NH 4 + . Together with the minimal production of nitrate, this confirmed that the conversion of NH 4 + to nitrogen gas was electrochemically achievable. The monitoring of treatment performance with varying key parameters (e.g., current density, H 2 O 2 feeding rate, pH, NaCl loading, and DSA type) led to the optimization of two component systems. The comparative evaluation of two sequentially combined systems (i.e., the E-Fenton-EC system versus the EC-E-Fenton system) using the mixture of phenol and NH 4 + under the predetermined optimal conditions suggested the superiority of the E-Fenton-EC system in terms of treatment efficiency and energy consumption. Finally, the sequential E-Fenton-EC process effectively mineralized organic carbon and decomposed NH 4 + -N in the real ADFW without external supply of NaCl.

  3. The reactor design and comparison of Fenton, electro-Fenton and photoelectro-Fenton processes for mineralization of benzene sulfonic acid (BSA)

    International Nuclear Information System (INIS)

    Ting, W.-P.; Lu, M.-C.; Huang, Y.-H.

    2008-01-01

    A new approach for promoting ferric reduction efficiency using a different electrochemical cell and the photoelectro-Fenton process has been developed. The use of UVA light and electric current as electron donors can efficiently initiate the Fenton reaction. Benzene sulfonic acid (BSA) was the target compound in this study. The parameters investigated to evaluate the reactor design include the electrode working area, electrode distance, energy consumption. Furthermore, the study also contains the intermediates and the mineralization efficiency of electrolysis, Fenton, electro-Fenton and photoelectro-Fenton process. Oxalic acid, the major intermediate of aromatic compound degradation, can complex with ferric ions. Meanwhile, a double cathode reactor could increase the current efficiency by 7%, which would translate to greater ferrous production and a higher degradation rate. Although the current efficiency of an electrode distance 5.5 cm device is 19% higher than 3.0 cm, results show that after 2 h of electrolysis the electronic expense using an electrode gap of 5.5 cm is much higher than 3.0 cm. The final TOC removal efficiency was 46, 64 and 72% using the Fenton, electro-Fenton and photoelectron-Fenton processes, respectively

  4. Combined treatment of retting flax wastewater using Fenton oxidation and granular activated carbon

    OpenAIRE

    Abou-Elela, Sohair I.; Ali, Mohammed Eid M.; Ibrahim, Hanan S.

    2016-01-01

    The process of retting flax produces a huge amount of wastewater which is characterized with bad unpleasant smell and high concentration of organic materials. Treatment of such waste had always been difficult because of the presence of refractory organic pollutants such as lignin. In this study, treatment of retting wastewater was carried out using combined system of Fenton oxidation process followed by adsorption on granular activated carbon (GAC). The effects of operating condition on Fento...

  5. Fenton oxidation treatment of spent wash-off liquor for reuse in reactive dying

    International Nuclear Information System (INIS)

    Mangat, A.; Shaikh, I.A.; Ahmed, F.; Baqar, M

    2014-01-01

    The use of clean and high quality water in textile dyeing process is very expensive. In this study, the potential of reusing Fenton treated wash-off wastewater generated at the end of reactive dyeing was investigated. The treated wastewater was used in several dyeings employing three widely used reactive dyes, C. I. Reactive Yellow 145, C. I. Reactive Red 194, and C. I. Reactive Blue 221. Experimental results showed that at acidic pH (3.5) using optimized quantities of FeSO/sub 4/ and H/sub 2/O/sub 2/, Fenton process yielded a significant reduction (80-99%) of colour and COD in 30 minutes of treatment time. New dyeings were then carried out in Fenton decolourized wash-off wastewater, and dyed fabric samples were subjected to quality evaluations in terms of wash fastness, crock fastness, and colour difference properties (delta L*, delta c*, delta h*, and delta E*). This study concluded that Fenton oxidation was an efficient method for the treatment of textile wash-off wastewater, and treated liquor can be effectively recycled in next dyeing, without compromising quality parameters. This method proved to be an eco-friendly process owing to the fact that it did not use any fresh water. (author)

  6. Removal of organic pollutants from produced water using Fenton oxidation

    Directory of Open Access Journals (Sweden)

    Afzal Talia

    2018-01-01

    Full Text Available Produced water (PW is the largest stream of wastewater from oil and gas exploration. It is highly polluted and requires proper treatment before disposal. The main objective of this study was to investigate the effectiveness of Fenton oxidation in degradation of organic matter in PW. The role of operating factors viz., H2O2 concentration (0.12 × 10-3 moles/L to 3 moles/L, [H2O2]/[Fe2+] molar ratio (2 to 75, and reaction time (30 to 200 minutes, on COD removal was determined through a series of batch experiments conducted in acidic environment at room temperature. The experiments were conducted with 500 mL PW samples in 1L glass beakers covered on the outside with aluminum foil to protect them from sunlight. Pre-decided amounts of ferrous sulfate heptahydrate (FeSO4.7H2O and hydrogen peroxide (H2O2 were added to initiate the Fenton reaction. An increase in COD removal was observed with increase in reaction time and [H2O2]/[Fe2+] molar ratio. COD removal also increased with H2O2 concentration up to 0.01 moles/L; further increase in H2O2 concentration decreased the COD removal efficiency. Over 90% COD removal was achieved under optimum reaction conditions. The study indicates that Fenton oxidation is effective for remediation of PW in terms of organic matter removal.

  7. Removal of organic pollutants from produced water using Fenton oxidation

    Science.gov (United States)

    Afzal, Talia; Hasnain Isa, Mohamed; Mustafa, Muhammad Raza ul

    2018-03-01

    Produced water (PW) is the largest stream of wastewater from oil and gas exploration. It is highly polluted and requires proper treatment before disposal. The main objective of this study was to investigate the effectiveness of Fenton oxidation in degradation of organic matter in PW. The role of operating factors viz., H2O2 concentration (0.12 × 10-3 moles/L to 3 moles/L), [H2O2]/[Fe2+] molar ratio (2 to 75), and reaction time (30 to 200 minutes), on COD removal was determined through a series of batch experiments conducted in acidic environment at room temperature. The experiments were conducted with 500 mL PW samples in 1L glass beakers covered on the outside with aluminum foil to protect them from sunlight. Pre-decided amounts of ferrous sulfate heptahydrate (FeSO4.7H2O) and hydrogen peroxide (H2O2) were added to initiate the Fenton reaction. An increase in COD removal was observed with increase in reaction time and [H2O2]/[Fe2+] molar ratio. COD removal also increased with H2O2 concentration up to 0.01 moles/L; further increase in H2O2 concentration decreased the COD removal efficiency. Over 90% COD removal was achieved under optimum reaction conditions. The study indicates that Fenton oxidation is effective for remediation of PW in terms of organic matter removal.

  8. Degradation of black liquor from bioethanol process using coagulation and Fenton-like methods

    Science.gov (United States)

    Muryanto, Muryanto; Sari, Ajeng Arum; Abimanyu, Haznan

    2017-01-01

    Black liquor is one of the main by-products of the pretreatment process in bioethanol production from oil palm empty fruit bunches. Black liquor wastewater releases black coloured effluent with high chemical oxygen demand (COD) and low dissolved oxygen (DO). It had a distinctive dark coloration, high alkalinity (pH=13), high organic content (COD > 50,000 ppm) and a high solid content (TSS > 5,000 ppm). Lignin destruction can be done by using high oxidation from OH radical system such as advanced oxidation processes (AOPs). Thereafter, the high concentration of COD, color, and TSS can be removed. The general aim of the present investigation was to determine degradation of black liquor wastewater by using a combined coagulation and Fenton-like methods. In this research, we use Poly Aluminum Chloride (PAC) as a coagulant and FeCl3.6H2O and H2O2 for Fenton-like's reagent. The process was conducted in jar test at 200 rpm for 30 minutes and after that slowly mixed for 2 hours and left for sedimentation 24 hours. 50 ml black liquor was added with variation dose of 1-5% PAC, and 10 % Fenton-like reagent. Hydroxyl radical was generated by the Fenton-like's reagent (ratio FeCl3.6H2O : H2O2 was varied). The highest decolorization of black liquor 70 % was obtained under 5% PAC coagulant. The pH of the wastewater was reduced from 13.00 to 8.07 after the addition of the coagulant. The decolorization of original black liquor was approximately 58% through the Fenton-like process. The combination of PAC and Fenton-like reagent has able to enhance the decolorization of black liquor up to 97%.

  9. Combined photo-Fenton-SBR process for antibiotic wastewater treatment

    Energy Technology Data Exchange (ETDEWEB)

    Elmolla, Emad S., E-mail: em_civil@yahoo.com [Department of Civil Engineering, Faculty of Engineering, Al-Azhar University, Cairo (Egypt); Chaudhuri, Malay [Department of Civil Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia)

    2011-09-15

    Highlights: {center_dot} The work focused on hazardous wastewater (antibiotic wastewater) treatment. {center_dot} Complete degradation of the antibiotics achieved by the treatment process. {center_dot} The SBR performance was found to be very sensitive to BOD{sub 5}/COD ratio below 0.40. {center_dot} Combined photo-Fenton-SBR process is a feasible treatment process for the antibiotic wastewater. - Abstract: The study examined combined photo-Fenton-SBR treatment of an antibiotic wastewater containing amoxicillin and cloxacillin. Optimum H{sub 2}O{sub 2}/COD and H{sub 2}O{sub 2}/Fe{sup 2+} molar ratio of the photo-Fenton pretreatment were observed to be 2.5 and 20, respectively. Complete degradation of the antibiotics occurred in one min. The sequencing batch reactor (SBR) was operated at different hydraulic retention times (HRTs) with the wastewater treated under different photo-Fenton operating conditions (H{sub 2}O{sub 2}/COD and H{sub 2}O{sub 2}/Fe{sup 2+} molar ratio). The SBR performance was found to be very sensitive to BOD{sub 5}/COD ratio of the photo-Fenton treated wastewater. Statistical analysis of the results indicated that it was possible to reduce the Fe{sup 2+} dose and increase the irradiation time of the photo-Fenton pretreatment. The best operating conditions of the combined photo-Fenton-SBR treatment were observed to be H{sub 2}O{sub 2}/COD molar ratio 2, H{sub 2}O{sub 2}/Fe{sup 2+} molar ratio 150, irradiation time 90 min and HRT of 12 h. Under the best operating conditions, 89% removal of sCOD with complete nitrification was achieved and the SBR effluent met the discharge standards.

  10. Combined photo-Fenton-SBR process for antibiotic wastewater treatment

    International Nuclear Information System (INIS)

    Elmolla, Emad S.; Chaudhuri, Malay

    2011-01-01

    Highlights: · The work focused on hazardous wastewater (antibiotic wastewater) treatment. · Complete degradation of the antibiotics achieved by the treatment process. · The SBR performance was found to be very sensitive to BOD 5 /COD ratio below 0.40. · Combined photo-Fenton-SBR process is a feasible treatment process for the antibiotic wastewater. - Abstract: The study examined combined photo-Fenton-SBR treatment of an antibiotic wastewater containing amoxicillin and cloxacillin. Optimum H 2 O 2 /COD and H 2 O 2 /Fe 2+ molar ratio of the photo-Fenton pretreatment were observed to be 2.5 and 20, respectively. Complete degradation of the antibiotics occurred in one min. The sequencing batch reactor (SBR) was operated at different hydraulic retention times (HRTs) with the wastewater treated under different photo-Fenton operating conditions (H 2 O 2 /COD and H 2 O 2 /Fe 2+ molar ratio). The SBR performance was found to be very sensitive to BOD 5 /COD ratio of the photo-Fenton treated wastewater. Statistical analysis of the results indicated that it was possible to reduce the Fe 2+ dose and increase the irradiation time of the photo-Fenton pretreatment. The best operating conditions of the combined photo-Fenton-SBR treatment were observed to be H 2 O 2 /COD molar ratio 2, H 2 O 2 /Fe 2+ molar ratio 150, irradiation time 90 min and HRT of 12 h. Under the best operating conditions, 89% removal of sCOD with complete nitrification was achieved and the SBR effluent met the discharge standards.

  11. Degradation of dyestuff materials by fenton oxidation, Part 4

    International Nuclear Information System (INIS)

    Shahrour, Kh.; Hachem, Ch.; Karabet, F.

    2008-01-01

    The oxidative degradation of various kinds of dyes (Azo carmine B, Tartrazine, Calcon, Methyle Orange, and Coomassie Brilliant Blue G 250, Methylene Blue, Bismark Brown Y(G) and Black 5) have been studied using Fenton's reagent (Fe 2+ and H 2 O 2 ). Many experiments were carried out on Azo carmine B as a model with initial concentration of 10 -4 to investigate the process's optimal conditions, pH, H 2 O 2 dosage, Fe 2+ dosage , temperature. The optimal conditions found were: pH=3, [H 2 O 2 ]=3 x 10 -3 M, [Fe 2+ ]=10 -4 M, t=60 Centigrade. under these contritions it was observed that Azo carmine B can be degraded at high extent (96.46%) after 50 min, however, the mineralization reached only (31.2%) in term of TOC and (41.1%) in term of COD. Results show that dyes are decomposed in two-stage reaction. In the first stage (Fe 2= /H 2 O 2 ) dyes decomposes rapidly within 0.5-5 min and the reaction obeys the pseudo-first-order. In the second stage (Fe 3+ /H 2 O 2 ) the dye decomposition is somewhat less rapidly, and the reaction follows the first order rate kinetic with respect to the dye concentration. (author)

  12. Evaluation of the mercaptobenzothiazole degradation by combined adsorption process and Fenton reaction using iron mining residue.

    Science.gov (United States)

    Martins, Adriana Lau da Silva; Teixeira, Luís Alberto César; da Fonseca, Fabiana Valéria; Yokoyama, Lídia

    2017-08-01

    The present study investigated the degradation of mercaptobenzothiazole (MBT), evaluating homogeneous and heterogeneous systems. An iron mineral residue from the desliming step of iron mining was used as a source in the Fenton-like reaction (advanced oxidation process). A granulometric analysis of the residue was performed and yielded fractions with high hematite (Fe 2 O 3 ) and low quartz content in sieves from 74 to below 44 mm. In this particle size range, the hematite content from 58.9% to 67.4% and the Brunauer-Emmett-Teller area from 0.1345 to 1.3137 m 2  g -1 were obtained. The zeta potential curves as a function of pH were obtained for the residue, the MBT solution and mixtures thereof. The adsorption of MBT in the residue and its degradation through the Fenton-like reaction were investigated. Adsorption tests and the Fenton-like reaction were carried out, where the MBT species and the residue are oppositely charged, yielding, respectively, 10% MBT adsorption on the surface of the residue and 100% MBT degradation by the Fenton-like reaction at pH 3, hydrogen peroxide concentration of 25 mg L -1 , residue concentration of 3 g L -1 , 200 rpm and 25°C, from a 100 mg L -1 MBT solution. MBT degradation was found to occur mainly by the heterogeneous Fenton-like process.

  13. Ultrasound coupled with Fenton oxidation pre-treatment of sludge to release organic carbon, nitrogen and phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Changxiu [School of Environment, Tsinghua University, Beijing 100084 (China); Jiang, Jianguo, E-mail: jianguoj@mail.tsinghua.edu.cn [School of Environment, Tsinghua University, Beijing 100084 (China); Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China (China); Collaborative Innovation Center for Regional Environmental Quality, Tsinghua University, Beijing (China); Li, De' an [School of Environment, Tsinghua University, Beijing 100084 (China)

    2015-11-01

    We focused on the effects of ultrasound and Fenton reagent in ultrasonic coupling Fenton oxidation (U + F) pre-treatment processes on the disintegration of wastewater treatment plant sludge. The results demonstrated that U + F treatment could significantly increase soluble COD, TOC, total N, proteins, total P and PO{sub 4}{sup 3−} concentrations in sludge supernatant. This method was more effective than ultrasonic (U) or Fenton oxidation (F) treatment alone. U + F treatment increased the soluble COD by 2.1- and 1.4-fold compared with U and F alone, respectively. U + F treatment increased the total N and P by 1.7- and 2.2-fold, respectively, compared with F alone. After U + F treatment, sludge showed a considerably finer particle size and looser microstructure based on scanning electron microscopy, and the highest OH· signal intensity increased from 568.7 by F treatment to 1106.3 using electron spin resonance. This demonstrated that U + F treatment induces disintegration of sludge and release of organic carbon, nitrogen and phosphorus better. - Highlights: • Combined ultrasound–Fenton pre-treatment was proposed for sludge disintegration. • Ultrasound–Fenton significantly increased carbon, nitrogen and phosphorus release. • Higher level of OH· was detected after combined disintegration than Fenton.

  14. Ultrasound coupled with Fenton oxidation pre-treatment of sludge to release organic carbon, nitrogen and phosphorus

    International Nuclear Information System (INIS)

    Gong, Changxiu; Jiang, Jianguo; Li, De'an

    2015-01-01

    We focused on the effects of ultrasound and Fenton reagent in ultrasonic coupling Fenton oxidation (U + F) pre-treatment processes on the disintegration of wastewater treatment plant sludge. The results demonstrated that U + F treatment could significantly increase soluble COD, TOC, total N, proteins, total P and PO 4 3− concentrations in sludge supernatant. This method was more effective than ultrasonic (U) or Fenton oxidation (F) treatment alone. U + F treatment increased the soluble COD by 2.1- and 1.4-fold compared with U and F alone, respectively. U + F treatment increased the total N and P by 1.7- and 2.2-fold, respectively, compared with F alone. After U + F treatment, sludge showed a considerably finer particle size and looser microstructure based on scanning electron microscopy, and the highest OH· signal intensity increased from 568.7 by F treatment to 1106.3 using electron spin resonance. This demonstrated that U + F treatment induces disintegration of sludge and release of organic carbon, nitrogen and phosphorus better. - Highlights: • Combined ultrasound–Fenton pre-treatment was proposed for sludge disintegration. • Ultrasound–Fenton significantly increased carbon, nitrogen and phosphorus release. • Higher level of OH· was detected after combined disintegration than Fenton

  15. Removal of organic pollutants from industrial wastewater by applying photo-Fenton oxidation technology

    OpenAIRE

    Ebrahiem E. Ebrahiem; Mohammednoor N. Al-Maghrabi; Ahmed R. Mobarki

    2017-01-01

    The general strategy of this study was based on evaluation of the possibility of applying advanced photo-oxidation technique (Fenton oxidation process) for removal of the residuals organic pollutants present in cosmetic wastewater. The different parameters that affect the chemical oxidation process for dyes in their aqueous solutions were studied by using Fenton’s reaction. These parameters are pH, hydrogen peroxide (H2O2) dose, ferrous sulfate (FeSO4·7H2O) dose, Initial dye concentration, an...

  16. Fenton oxidation to remediate PAHs in contaminated soils: A critical review of major limitations and counter-strategies.

    Science.gov (United States)

    Usman, M; Hanna, K; Haderlein, S

    2016-11-01

    Fenton oxidation constitutes a viable remediation strategy to remove polycyclic aromatic hydrocarbons (PAHs) in contaminated soils. This review is intended to illustrate major limitations associated with this process like acidification, PAH unavailability, and deterioration of soil quality along with associated factors, followed by a critical description of various developments to overcome these constraints. Considering the limitation that its optimal pH is around 3, traditional Fenton treatment could be costly, impractical in soil due to the high buffering capacity of soils and associated hazardous effects. Use of various chelating agents (organic or inorganic) allowed oxidation at circumneutral pH but factors like higher oxidant demand, cost and toxicity should be considered. Another alternative is the use of iron minerals that can catalyze Fenton-like oxidation over a wide range of pH, but mobility of these particles in soils (i.e. saturated and unsaturated zones) should be investigated prior to in-situ applications. The PAH-unavailability is the crucial limitation hindering their effective degradation. Research data is compiled describing various strategies to address this issue like the use of availability enhancement agents, extraction or thermal pretreatment. Last section of this review is devoted to describe the effects of various developments in Fenton treatment onto soil quality and native microbiota. Finally, research gaps are discussed to suggest future directions in context of applying Fenton oxidation to remediate contaminated soils. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Assessment of the advanced oxidation process , photo-fenton, on the degradation of polyaromatics hydrocarbons contained on the aqueous part of oil in superficial sea water; Avaliacao do processo oxidativo avancado, foto-fenton, na degradacao dos hidrocarbonetos poliaromaticos contidos na fracao soluvel do petroleo em agua superficial salina

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Rita C.R. da; Silva, Valdinete L. da; Paim, Ana Paula Silveira [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Rocha, Otidene R.S. da; Duarte, Marcia M.L. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2008-07-01

    The pollution for oil has been one of the main ambient problems of the last decades. It exists an increasing interest in the study of the destination and forms of disappearance of the constituent hydrocarbons of the oil aiming at the development of more efficient methods of removal of the same ones of the environment. With objective to evaluate the process photo-fenton, in the treatment of the contaminated saline superficial water with polyaromatics hydrocarbons (HPAs) contained in the crude oil, mounted an experiment using reactor of black light, the hydrogen peroxide as oxidant agent. After the degradation the samples had been submitted to the analysis in the GC-MS, and for the 31 specters it was observed that the best ones resulted had been gotten when mmol of H{sub 2}O{sub 2} in 8 was used h of exposition to the irradiation and with pH of the equal system the 4. In the specter of this assay the characteristic peaks of the HPAs disappear completely or appear in a lowly intensities, proving that it had rupture of aromatical rings consequently and the degradation of the same ones or that its concentrations meet below of the limit of detention of the equipment. Soon, with the gotten results it can be concluded that the POAs, in special the process photo-fenton, is presented as a viable alternative in the contaminated saline superficial water treatment with the HPAs contained in the rude oil. (author)

  18. Sodium hypochlorite as an alternative to hydrogen peroxide in Fenton process for industrial scale.

    Science.gov (United States)

    Behin, Jamshid; Akbari, Abbas; Mahmoudi, Mohsen; Khajeh, Mehdi

    2017-09-15

    In present work, the treatment of aromatic compounds of simulated wastewater was performed by Fenton and NaOCl/Fe 2+ processes. The model solution was prepared based on the wastewater composition of Diisocyanate unit of Karoon Petrochemical Company/Iran containing Diamino-toluenes, Nitro-phenol, Mononitro-toluene, Nitro-cresol, and Dinitro-toluene. Experiments were conducted in a batch mode to examine the effects of operating variables such as pH, oxidant dosages, ferrous ion concentration and numbers of feeding on COD removal. Taguchi experimental design was used to determine the optimum conditions. The COD removal efficiency under optimum conditions (suggested by Taguchi design) in Fenton and NaOCl/Fe 2+ processes was 88.7% and 83.4%, respectively. The highest contribution factor in Fenton process belongs to pH (47.47%) and in NaOCl/Fe 2+ process belongs to NaOCl/pollutants (50.26%). High regression coefficient (R 2 : 0.98) obtained for Taguchi method, indicates that models are statistically significant and are in well agreement with each other. The NaOCl/Fe 2+ process utilizing a conventional oxidant, in comparison to hydrogen peroxide, is an efficient cost effective process for COD removal from real wastewater, although the removal efficiency is not as high as in Fenton process; however it is a suitable process to replace Fenton process in industrial scale for wastewater involved aromatic compounds with high COD. This process was successfully applied in Karoon Petrochemical Company/Iran. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Fenton oxidative decolorization of the azo dye Direct Blue 15 in aqueous solution

    DEFF Research Database (Denmark)

    Sun, Jian-Hui; Shi, Shao-Hui; Lee, Yi-Fan

    2009-01-01

    In this paper, the application of Fenton oxidation process for the decolorization of an azo dye Direct Blue 15 (DB15) in aqueous solution was investigated. The effect of initial pH, dosage of H2O2, H2O2/Fe2+ and H2O2/dye ratios and the reaction temperature on the decolorization efficiency...... = 60: 1 and temperature = 30 degrees C. Under the optimal conditions, 4.7 x 10(-5) mol/L of the DB15 aqueous solution can be completely decolorized by Fenton oxidation within 50-min reaction time and the decolorization kinetic rate constant k was determined as 0.1694 min(-1). Additionally increasing...... the reaction temperature from 20 to 40 degrees C showed a positive effect on the decolorization efficiency of DB15. The present study can provide guidance to relational industry operators and planners to effectively treat the DB15 contaminated wastewater by Fenton oxidation process. (C) 2009 Elsevier B. V. All...

  20. Roles of free radicals in NO oxidation by Fenton system and the enhancement on NO oxidation and H2O2 utilization efficiency.

    Science.gov (United States)

    Zhao, Haiqian; Dong, Ming; Wang, Zhonghua; Wang, Huaiyuan; Qi, Hanbing

    2018-06-20

    Low H 2 O 2 utilization efficiency is the main problem when Fenton system was used to oxidize NO in flue gas. To understand the behavior of the free radicals during NO oxidation process in Fenton system is crucial to solving this problem. The oxidation capacity of ·OH and HO 2 · on NO in Fenton system was compared and the useless consumption path of ·OH and HO 2 · that caused the low utilization efficiency of H 2 O 2 were studied. A method to enhance the oxidation ability and H 2 O 2 utilization efficiency by adding reducing additives in Fenton system was proposed. The results showed that both of ·OH and HO 2 · were active substances that oxidize NO. However, the oxidation ability of ·OH radicals was stronger. The vast majority of ·OH and HO 2 · was consumed by rapid reaction ·OH+HO 2 ·→H 2 O+O 2 , which was the primary reason for the low utilization efficiency of H 2 O 2 in Fenton system. Hydroxylamine hydrochloride and ascorbic acid could accelerate the conversion of Fe 3+ to Fe 2+ , thereby increase the generation rate of ·OH and decrease the generation rate of HO 2 ·. As a result, the oxidation ability and H 2 O 2 utilization efficiency were enhanced.

  1. ADVANTAGES/DISADVANTAGES FOR ISCO METHODS IN-SITU FENTON OXIDATION IN-SITU PERMANGANATE OXIDATION

    Science.gov (United States)

    The advantages and disadvantages of in-situ Fenton oxidation and in-situ permanganate oxidation will be presented. This presentation will provide a brief overview of each technology and a detailed analysis of the advantages and disadvantages of each technology. Included in the ...

  2. Treating leachate with advanced oxidation: applying Fenton's reagent; Oxidaciones avanzadas para el tratamiento de lixiviado: aplicacion del Reactivo de Fenton

    Energy Technology Data Exchange (ETDEWEB)

    Maranonn Ruiz, I.; Sancho Seuma, L.

    2003-07-01

    The present study investigates the removal of refractory organics by Advanced Oxidation Process: Fenton's Reaction. A batch test protocol was designed to study the oxidation and coagulation in Fenton Reaction. The batch tests were conducted to determine the optimum conditions for the plant operation such as pH, H{sub 2}O{sub 2} dosage, FeSO{sub 4} dosage and contact time. It was found that the highest removal efficiencies of COD were with the oxidation at acid pH around 3 and the coagulation at basic pH around 8, few minutes of treatment time, the initial concentrations of H{sub 2}O{sub 2} were in the range 68-1550 mg/l and the different dosages of FeSO{sub 4} were in the range 487-3038 mg/l. They were added in determinate proportions to get the highest efficiency of producing OH, DBO{sub 5}/DQO ratio was decreased from 0,3 to 0,1. Therefore Fenton's reaction process is a very effective means for a pretreatment or tertiary treatment of biological methods. (Author) 20 refs.

  3. Pretreatment of furfural industrial wastewater by Fenton, electro-Fenton and Fe(II)-activated peroxydisulfate processes: a comparative study.

    Science.gov (United States)

    Yang, C W; Wang, D; Tang, Q

    2014-01-01

    The Fenton, electro-Fenton and Fe(II)-activated peroxydisulfate (PDS) processes have been applied for the treatment of actual furfural industrial wastewater in this paper. Through the comparative study of the three processes, a suitable pretreatment technology for actual furfural wastewater treatment was obtained, and the mechanism and dynamics process of this technology is discussed. The experimental results show that Fenton technology has a good and stable effect without adjusting pH of furfural wastewater. At optimal conditions, which were 40 mmol/L H₂O₂ initial concentration and 10 mmol/L Fe²⁺ initial concentration, the chemical oxygen demand (COD) removal rate can reach 81.2% after 90 min reaction at 80 °C temperature. The PDS process also has a good performance. The COD removal rate could attain 80.3% when Na₂S₂O₈ initial concentration was 4.2 mmol/L, Fe²⁺ initial concentration was 0.1 mol/L, the temperature remained at 70 °C, and pH value remained at 2.0. The electro-Fenton process was not competent to deal with the high-temperature furfural industrial wastewater and only 10.2% COD was degraded at 80 °C temperature in the optimal conditions (2.25 mA/cm² current density, 4 mg/L Na₂SO₄, 0.3 m³/h aeration rate). For the Fenton, electro-Fenton and PDS processes in pretreatment of furfural wastewater, their kinetic processes follow the pseudo first order kinetics law. The pretreatment pathways of furfural wastewater degradation are also investigated in this study. The results show that furfural and furan formic acid in furfural wastewater were preferentially degraded by Fenton technology. Furfural can be degraded into low-toxicity or nontoxic compounds by Fenton pretreatment technology, which could make furfural wastewater harmless and even reusable.

  4. Decolourisation of dyes under electro-Fenton process using Fe alginate gel beads

    Energy Technology Data Exchange (ETDEWEB)

    Rosales, E.; Iglesias, O.; Pazos, M. [Department of Chemical Engineering, University of Vigo, Isaac Newton Building, Campus As Lagoas, Marcosende 36310, Vigo (Spain); Sanroman, M.A., E-mail: sanroman@uvigo.es [Department of Chemical Engineering, University of Vigo, Isaac Newton Building, Campus As Lagoas, Marcosende 36310, Vigo (Spain)

    2012-04-30

    Highlights: Black-Right-Pointing-Pointer Catalytic activity of Fe alginate gel beads for the remediation of wastewater was tested. Black-Right-Pointing-Pointer New electro-Fenton process for the remediation of polluted wastewater. Black-Right-Pointing-Pointer Continuous dye treatment without operational problem with high removal. - Abstract: This study focuses on the application of electro-Fenton technique by use of catalytic activity of Fe alginate gel beads for the remediation of wastewater contaminated with synthetic dyes. The Fe alginate gel beads were evaluated for decolourisation of two typical dyes, Lissamine Green B and Azure B under electro-Fenton process. After characterization of Fe alginate gel beads, the pH effect on the process with Fe alginate beads and a comparative study of the electro-Fenton process with free Fe and Fe alginate bead was done. The results showed that the use of Fe alginate beads increases the efficiency of the process; moreover the developed particles show a physical integrity in a wide range of pH (2-8). Around 98-100% of dye decolourisation was obtained for both dyes by electro-Fenton process in successive batches. Therefore, the process was performed with Fe alginate beads in a bubble continuous reactor. High color removal (87-98%) was attained for both dyes operating at a residence time of 30 min, without operational problems and maintaining particle shapes throughout the oxidation process. Consequently, the stable performance of Fe alginate beads opens promising perspectives for fast and economical treatment of wastewater polluted by dyes or similar organic contaminants.

  5. Decolourisation of dyes under electro-Fenton process using Fe alginate gel beads

    International Nuclear Information System (INIS)

    Rosales, E.; Iglesias, O.; Pazos, M.; Sanromán, M.A.

    2012-01-01

    Highlights: ► Catalytic activity of Fe alginate gel beads for the remediation of wastewater was tested. ► New electro-Fenton process for the remediation of polluted wastewater. ► Continuous dye treatment without operational problem with high removal. - Abstract: This study focuses on the application of electro-Fenton technique by use of catalytic activity of Fe alginate gel beads for the remediation of wastewater contaminated with synthetic dyes. The Fe alginate gel beads were evaluated for decolourisation of two typical dyes, Lissamine Green B and Azure B under electro-Fenton process. After characterization of Fe alginate gel beads, the pH effect on the process with Fe alginate beads and a comparative study of the electro-Fenton process with free Fe and Fe alginate bead was done. The results showed that the use of Fe alginate beads increases the efficiency of the process; moreover the developed particles show a physical integrity in a wide range of pH (2–8). Around 98–100% of dye decolourisation was obtained for both dyes by electro-Fenton process in successive batches. Therefore, the process was performed with Fe alginate beads in a bubble continuous reactor. High color removal (87–98%) was attained for both dyes operating at a residence time of 30 min, without operational problems and maintaining particle shapes throughout the oxidation process. Consequently, the stable performance of Fe alginate beads opens promising perspectives for fast and economical treatment of wastewater polluted by dyes or similar organic contaminants.

  6. Bio-Electro-Fenton process for the degradation of Non-Steroidal Anti-Inflammatory Drugs in wastewater

    DEFF Research Database (Denmark)

    Nadais, Helena; Li, Xiaohu; Alves, Nadine

    2018-01-01

    Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) are ubiquitous municipal wastewater pollutants of which several are resistant to degradation in conventional wastewater treatment, and represent a major environmental health concern worldwide. An alternative treatment, the bio-electro-Fenton process......, has received increasing attention in past years. In this process the strong oxidant •HO is formed using the electrons derived from bacterial oxidation of organic substrate. In this work, a laboratory scale microbial electrolysis cell based bio-electro-Fenton process was developed for the treatment...

  7. Iron oxide-mediated semiconductor photocatalysis vs. heterogeneous photo-Fenton treatment of viruses in wastewater. Impact of the oxide particle size.

    Science.gov (United States)

    Giannakis, Stefanos; Liu, Siting; Carratalà, Anna; Rtimi, Sami; Talebi Amiri, Masoud; Bensimon, Michaël; Pulgarin, César

    2017-10-05

    The photo-Fenton process is recognized as a promising technique towards microorganism disinfection in wastewater, but its efficiency is hampered at near-neutral pH operating values. In this work, we overcome these obstacles by using the heterogeneous photo-Fenton process as the default disinfecting technique, targeting MS2 coliphage in wastewater. The use of low concentrations of iron oxides in wastewater without H 2 O 2 (wüstite, maghemite, magnetite) has demonstrated limited semiconductor-mediated MS2 inactivation. Changing the operational pH and the size of the oxide particles indicated that the isoelectric point of the iron oxides and the active surface area are crucial in the success of the process, and the possible underlying mechanisms are investigated. Furthermore, the addition of low amounts of Fe-oxides (1mgL -1 ) and H 2 O 2 in the system (1, 5 and 10mgL -1 ) greatly enhanced the inactivation process, leading to heterogeneous photo-Fenton processes on the surface of the magnetically separable oxides used. Additionally, photo-dissolution of iron in the bulk, lead to homogeneous photo-Fenton, further aided by the complexation by the dissolved organic matter in the solution. Finally, we assess the impact of the presence of the bacterial host and the difference caused by the different iron sources (salts, oxides) and the Fe-oxide size (normal, nano-sized). Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Application of Electro-Fenton Technology to Remediation of Polluted Effluents by Self-Sustaining Process

    Directory of Open Access Journals (Sweden)

    Maria Ángeles Fernández de Dios

    2014-01-01

    Full Text Available The applicability of electro-Fenton technology to remediation of wastewater contaminated by several organic pollutants such as dyes and polycyclic aromatic hydrocarbons has been evaluated using iron-enriched zeolite as heterogeneous catalyst. The electro-Fenton technology is an advanced oxidation process that is efficient for the degradation of organic pollutants, but it suffers from the high operating costs due to the need for power investment. For this reason, in this study microbial fuel cells (MFCs were designed in order to supply electricity to electro-Fenton processes and to achieve high treatment efficiency at low cost. Initially, the effect of key parameters on the MFC power generation was evaluated. Afterwards, the degradation of Reactive Black 5 dye and phenanthrene was evaluated in an electro-Fenton reactor, containing iron-enriched zeolite as catalyst, using the electricity supplied by the MFC. Near complete dye decolourization and 78% of phenanthrene degradation were reached after 90 min and 30 h, respectively. Furthermore, preliminary reusability tests of the developed catalyst showed high degradation levels for successive cycles. The results permit concluding that the integrated system is adequate to achieve high treatment efficiency with low electrical consumption.

  9. Application of Electro-Fenton Technology to Remediation of Polluted Effluents by Self-Sustaining Process

    Science.gov (United States)

    Fernández de Dios, Maria Ángeles; Iglesias, Olaia; Pazos, Marta; Sanromán, Maria Ángeles

    2014-01-01

    The applicability of electro-Fenton technology to remediation of wastewater contaminated by several organic pollutants such as dyes and polycyclic aromatic hydrocarbons has been evaluated using iron-enriched zeolite as heterogeneous catalyst. The electro-Fenton technology is an advanced oxidation process that is efficient for the degradation of organic pollutants, but it suffers from the high operating costs due to the need for power investment. For this reason, in this study microbial fuel cells (MFCs) were designed in order to supply electricity to electro-Fenton processes and to achieve high treatment efficiency at low cost. Initially, the effect of key parameters on the MFC power generation was evaluated. Afterwards, the degradation of Reactive Black 5 dye and phenanthrene was evaluated in an electro-Fenton reactor, containing iron-enriched zeolite as catalyst, using the electricity supplied by the MFC. Near complete dye decolourization and 78% of phenanthrene degradation were reached after 90 min and 30 h, respectively. Furthermore, preliminary reusability tests of the developed catalyst showed high degradation levels for successive cycles. The results permit concluding that the integrated system is adequate to achieve high treatment efficiency with low electrical consumption. PMID:24723828

  10. Use of Pillared Clay-Based Catalysts for Wastewater Treatment through Fenton-Like Processes

    OpenAIRE

    J. Herney-Ramírez; Luis M. Madeira

    2010-01-01

    Clays, both natural and physical-chemically modified, are attractive materials for the preparation of supported catalysts. In this chapter, a review is made regarding the use of pillared interlayered clays (PILCs) in heterogeneous Fenton-like advanced oxidation processes. Their applications in pollutants degradation is summarized, with particular emphasis on the effect of the main operating conditions (e.g., initial H2O2 or parent compound concentration, catalyst load, pH, or temperature) on ...

  11. Iron oxide nanotube layer fabricated with electrostatic anodization for heterogeneous Fenton like reaction

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Jun-Won; Park, Jae-Woo, E-mail: jaewoopark@hanyang.ac.kr

    2014-05-01

    Highlights: • Iron oxide nanotube was newly fabricated with potentiostatic anodization of Fe{sup 0} foil. • Cyanide was oxidized more effectively with the iron oxide nanotube and H{sub 2}O{sub 2}, resulting in fast oxidation of cyanide and cyanate. • This nanotube of Fe{sub 2}O{sub 3} on Fe{sup 0} metal can replace conventional particulate iron catalysts in Fenton-like processes. - Abstract: Iron oxide nanotubes (INT) were fabricated with potentiostatic anodization of zero valent iron foil in 1 M Na{sub 2}SO{sub 4} containing 0.5 wt% NH{sub 4}F electrolyte, holding the potential at 20, 40, and 60 V for 20 min, respectively. Field emission scanning electron microscopy and X-ray diffractometry were used to evaluate the morphology and crystalline structure of the INT film. The potential of 40 V for 20 min was observed to be optimal to produce an optimal catalytic film. Cyanide dissolved in water was degraded through the Fenton-like reaction using the INT film with hydrogen peroxide (H{sub 2}O{sub 2}). In case of INT-40 V in the presence of H{sub 2}O{sub 2} 3%, the first-order rate constant was found to be 1.7 × 10{sup −2} min{sup −1}, and 1.2 × 10{sup −2} min{sup −1} with commercial hematite powder. Degradation of cyanide was much less with only H{sub 2}O{sub 2}. Therefore, this process proposed in this work can be an excellent alternative to traditional catalysts for Fenton-like reaction.

  12. Experimental Study on Treatment of Dyeing Wastewater by Activated Carbon Adsorption, Coagulation and Fenton Oxidation

    Science.gov (United States)

    Xiaoxu, SUN; Jin, XU; Xingyu, LI

    2017-12-01

    In this paper dyeing waste water was simulated by reactive brilliant blue XBR, activated carbon adsorption process, coagulation process and chemical oxidation process were used to treat dyeing waste water. In activated carbon adsorption process and coagulation process, the water absorbance values were measured. The CODcr value of water was determined in Fenton chemical oxidation process. Then, the decolorization rate and COD removal rate were calculated respectively. The results showed that the optimum conditions of activated carbon adsorption process were as follows: pH=2, the dosage of activated carbon was 1.2g/L, the adsorption reaction time was 60 min, and the average decolorization rate of the three parallel experiments was 85.30%. The optimum conditions of coagulation experiment were as follows: pH=8~9, PAC dosage was 70mg/L, stirring time was 20min, standing time was 45min, the average decolorization rate of the three parallel experiments was 74.48%. The optimum conditions for Fenton oxidation were Fe2+ 0.05g/L, H2O2 (30%) 14mL/L, pH=3, reaction time 40min. The average CODcr removal rate was 69.35% in three parallel experiments. It can be seen that in the three methods the activated carbon adsorption treatment of dyeing wastewater was the best one.

  13. Current advances and trends in electro-Fenton process using heterogeneous catalysts - A review.

    Science.gov (United States)

    Poza-Nogueiras, Verónica; Rosales, Emilio; Pazos, Marta; Sanromán, M Ángeles

    2018-06-01

    Over the last decades, advanced oxidation processes have often been used alone, or combined with other techniques, for remediation of ground and surface water pollutants. The application of heterogeneous catalysis to electrochemical advanced oxidation processes is especially useful due to its efficiency and environmental safety. Among those processes, electro-Fenton stands out as the one in which heterogeneous catalysis has been broadly applied. Thus, this review has introduced an up-to-date collation of the current knowledge of the heterogeneous electro-Fenton process, highlighting recent advances in the use of different catalysts such as iron minerals (pyrite, magnetite or goethite), prepared catalysts by the load of metals in inorganic and organic materials, nanoparticles, and the inclusion of catalysts on the cathode. The effects of physical-chemical parameters as well as the mechanisms involved are critically assessed. Finally, although the utilization of this process to remediation of wastewater overwhelmingly outnumber other utilities, several applications have been described in the context of regeneration of adsorbent or the remediation of soils as clear examples of the feasibility of the electro-Fenton process to solve different environmental problems. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. UV/Fenton photo-oxidation of Drimarene Dark Red (DDR) containing textile-dye wastewater

    Science.gov (United States)

    Hudaya, T.; Anthonios, J.; Septianto, E.

    2016-11-01

    Textile dye wastewater contains organic pollutants which are non-biodegradable, characterized by low BOD/COD ratio of typically Advanced Oxidation Processes (AOPs). One of the AOPs method which is the UV/H2O2/Fe2+ (or UV/Fenton) offers not only relatively low cost but also quite effective (in terms of color removal and reaction time) treatment. This particular research aimed to optimize the conditions of UV/Fenton photo-oxidation process for Drimarene Dark Red containing textile- dye wastewater. The two main operating conditions to be optimized were the initial concentration of H2O2 ranged between 0.022-0.078 %-w and the mol ratio of Fe2+: H2O2 was varied from 1: 13 up to 1: 45, using the Central Composite Design experimental matrix. The photo-oxidation was carried out at the optimum pH of 3 from some previous experiments. The best processing conditions of the photo-oxidation of Drimarene Dark Red (DDR) were found at the initial concentration of H2O2 at 0.050%-w and the mole ratio Fe2+: H2O2 of 1: 22. Under these conditions, the measured 2nd order pseudo-rate constantwas 0.021 M-1.min-1. The DDR color removal of 90% was surprisingly achievable within only 10 minutes reaction time.

  15. Oxidative Degradation of Phenol containing Wastewater using Fenton Reagent, Permanganate and Ultraviolet Radiation

    International Nuclear Information System (INIS)

    Abd El-Rahman, N.M.; Talaat, H.A.; Sorour, M.H.

    1999-01-01

    Phenol containing wastewaters are generated by numerous industrial units including integrated steel mills, textile mills, plastic production, etc. The present work is targeted to explore the viable oxidation techniques for degradation of phenolic wastewater. Three modes of treatment have been adopted in this study, namely, sole oxidant mode using Fenton reagent or permanganate, UV-assisted oxidation and two consequent chemical oxidation steps. Results indicated the superiority of fenton reagent over KMnO 4 oxidation in the sole oxidant mode. On the other hand, UV-assisted KMnO 4 oxidation enables almost complete COD reduction. Dual chemical oxidation mode employing KMnO 4 oxidation followed by Fenton reagent is also an efficient oxidative degradation system

  16. Electrochemical destruction of chlorophenoxy herbicides by anodic oxidation and electro-Fenton using a boron-doped diamond electrode

    International Nuclear Information System (INIS)

    Brillas, Enric; Boye, Birame; Sires, Ignasi; Garrido, Jose Antonio; Rodriguez, Rosa Maria; Arias, Conchita; Cabot, Pere-Lluis; Comninellis, Christos

    2004-01-01

    The degradation of herbicides 4-chlorophenoxyacetic acid (4-CPA), 4-chloro-2-methylphenoxyacetic acid (MCPA), 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) in aqueous medium of pH 3.0 has been comparatively studied by anodic oxidation and electro-Fenton using a boron-doped diamond (BDD) anode. All solutions are totally mineralized by electro-Fenton, even at low current, being the process more efficient with 1 mM Fe 2+ as catalyst. This is due to the production of large amounts of oxidant hydroxyl radical (OH·) on the BDD surface by water oxidation and from Fenton's reaction between added Fe 2+ and H 2 O 2 electrogenerated at the O 2 -diffusion cathode. The herbicide solutions are also completely depolluted by anodic oxidation. Although a quicker degradation is found at the first stages of electro-Fenton, similar times are required for achieving overall mineralization in both methods. The decay kinetics of all herbicides always follows a pseudo first-order reaction. Reversed-phase chromatography allows detecting 4-chlorophenol, 4-chloro-o-cresol, 2,4-dichlorophenol and 2,4,5-trichlorophenol as primary aromatic intermediates of 4-CPA, MCPA, 2,4-D and 2,4,5-T, respectively. Dechlorination of these products gives Cl - , which is slowly oxidized on BDD. Ion-exclusion chromatography reveals the presence of persistent oxalic acid in electro-Fenton by formation of Fe 3+ -oxalato complexes, which are slowly destroyed by OH· adsorbed on BDD. In anodic oxidation, oxalic acid is mineralized practically at the same rate as generated

  17. Enhancement of activated sludge disintegration and dewaterability by Fenton process

    Science.gov (United States)

    Heng, G. C.; Isa, M. H.

    2016-06-01

    Municipal and industrial wastewater treatment plants produce large amounts of sludge. This excess sludge is an inevitable drawback inherent to the activated sludge process. In this study, the waste activated sludge was obtained from the campus wastewater treatment plant at Universiti Teknologi PETRONAS (UTP), Malaysia. Fenton pretreatment was optimized by using the response surface methodology (RSM) to study the effects of three operating conditions including the dosage of H2O2 (g H2O2/kg TS), the molar ratio of H2O2/Fe2+ and reaction time. The optimum operating variables to achieve MLVSS removal 65%, CST reduction 28%, sCOD 11000 mg/L and EPS 500 mg/L were: 1000 g H2O2/kg TS, H2O2/Fe2+ molar ratio 70 and reaction time 45 min. Fenton process was proved to be able to enhance the sludge disintegration and dewaterability.

  18. Removal of azo dye using Fenton and Fenton-like processes: Evaluation of process factors by Box-Behnken design and ecotoxicity tests.

    Science.gov (United States)

    Fernandes, Neemias Cintra; Brito, Lara Barroso; Costa, Gessyca Gonçalves; Taveira, Stephânia Fleury; Cunha-Filho, Marcílio Sérgio Soares; Oliveira, Gisele Augusto Rodrigues; Marreto, Ricardo Neves

    2018-06-06

    The conventional treatment of textile effluents is usually inefficient in removing azo dyes and can even generate more toxic products than the original dyes. The aim of the present study was to optimize the process factors in the degradation of Disperse Red 343 by Fenton and Fenton-like processes, as well as to investigate the ecotoxicity of the samples treated under optimized conditions. A Box-Behnken design integrated with the desirability function was used to optimize dye degradation, the amount of residual H 2 O 2 [H 2 O 2residual ], and the ecotoxicity of the treated samples (lettuce seed, Artemia salina, and zebrafish in their early-life stages). Dye degradation was affected only by catalyst concentration [Fe] in both the Fenton and Fenton-like processes. In the Fenton reaction, [H 2 O 2residual ] was significantly affected by initial [H 2 O 2 ] and its interaction with [Fe]; however, in the Fenton-like reaction, it was affected by initial [H 2 O 2 ] only. A. salina mortality was affected by different process factors in both processes, which suggests the formation of different toxic products in each process. The desirability function was applied to determine the best process parameters and predict the responses, which were confirmed experimentally. Optimal conditions facilitated the complete degradation of the dye without [H 2 O 2residual ] or toxicity for samples treated with the Fenton-like process, whereas the Fenton process induced significant mortality for A. salina. Results indicate that the Fenton-like process is superior to the Fenton reaction to degrade Disperse Red 343. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Feasibility of bioleaching combined with Fenton oxidation to improve sewage sludge dewaterability.

    Science.gov (United States)

    Liu, Changgeng; Zhang, Panyue; Zeng, Chenghua; Zeng, Guangming; Xu, Guoyin; Huang, Yi

    2015-02-01

    A novel joint method of bioleaching with Fenton oxidation was applied to condition sewage sludge. The specific resistance to filtration (SRF) and moisture of sludge cake (MSC) were adopted to evaluate the improvement of sludge dewaterability. After 2-day bioleaching, the sludge pH dropped to about 2.5 which satisfied the acidic condition for Fenton oxidation. Meanwhile, the SRF declined from 6.45×10(10) to 2.07×10(10) s2/g, and MSC decreased from 91.42% to 87.66%. The bioleached sludge was further conditioned with Fenton oxidation. From an economical point of view, the optimal dosages of H2O2 and Fe2+ were 0.12 and 0.036 mol/L, respectively, and the optimal reaction time was 60 min. Under optimal conditions, SRF, volatile solids reduction, and MSC were 3.43×10(8) s2/g, 36.93%, and 79.58%, respectively. The stability and settleability of sewage sludge were both improved significantly. Besides, the results indicated that bioleaching-Fenton oxidation was more efficient in dewatering the sewage sludge than traditional Fenton oxidation. The sludge conditioning mechanisms by bioleaching-Fenton oxidation might mainly include the flocculation effects and the releases of extracellular polymeric substances-bound water and intercellular water. Copyright © 2014. Published by Elsevier B.V.

  20. Advanced landfill leachate treatment using iron-carbon microelectrolysis- Fenton process: Process optimization and column experiments

    International Nuclear Information System (INIS)

    Wang, Liqun; Yang, Qi; Wang, Dongbo; Li, Xiaoming; Zeng, Guangming; Li, Zhijun; Deng, Yongchao; Liu, Jun; Yi, Kaixin

    2016-01-01

    Highlights: • Fe-C microelectrolysis-Fenton process is proposed to pretreat landfill leachate. • Operating variables are optimized by response surface methodology (RSM). • 3D-EEMs and MW distribution explain the mechanism of enhanced biodegradability. • Fixed-bed column experiments are performed at different flow rates. - Abstract: A novel hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor was proposed for the pretreatment of mature landfill leachate. This reactor, combining microelectrolysis with Fenton process, revealed high treatment efficiency. The operating variables, including Fe-C dosage, H_2O_2 concentration and initial pH, were optimized by the response surface methodology (RSM), regarding the chemical oxygen demand (COD) removal efficiency and biochemical oxygen demand: chemical oxygen demand (BOD_5/COD) as the responses. The highest COD removal (74.59%) and BOD_5/COD (0.50) was obtained at optimal conditions of Fe-C dosage 55.72 g/L, H_2O_2 concentration 12.32 mL/L and initial pH 3.12. Three-dimensional excitation and emission matrix (3D-EEM) fluorescence spectroscopy and molecular weight (MW) distribution demonstrated that high molecular weight fractions such as refractory fulvic-like substances in leachate were effectively destroyed during the combined processes, which should be attributed to the combination oxidative effect of microelectrolysis and Fenton. The fixed-bed column experiments were performed and the breakthrough curves at different flow rates were evaluated to determine the practical applicability of the combined process. All these results show that the hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor is a promising and efficient technology for the treatment of mature landfill leachate.

  1. Advanced landfill leachate treatment using iron-carbon microelectrolysis- Fenton process: Process optimization and column experiments

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Liqun, E-mail: 691127317@qq.com [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Yang, Qi, E-mail: yangqi@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Wang, Dongbo [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Li, Xiaoming, E-mail: xmli121x@hotmail.com [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Zeng, Guangming; Li, Zhijun; Deng, Yongchao; Liu, Jun; Yi, Kaixin [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China)

    2016-11-15

    Highlights: • Fe-C microelectrolysis-Fenton process is proposed to pretreat landfill leachate. • Operating variables are optimized by response surface methodology (RSM). • 3D-EEMs and MW distribution explain the mechanism of enhanced biodegradability. • Fixed-bed column experiments are performed at different flow rates. - Abstract: A novel hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor was proposed for the pretreatment of mature landfill leachate. This reactor, combining microelectrolysis with Fenton process, revealed high treatment efficiency. The operating variables, including Fe-C dosage, H{sub 2}O{sub 2} concentration and initial pH, were optimized by the response surface methodology (RSM), regarding the chemical oxygen demand (COD) removal efficiency and biochemical oxygen demand: chemical oxygen demand (BOD{sub 5}/COD) as the responses. The highest COD removal (74.59%) and BOD{sub 5}/COD (0.50) was obtained at optimal conditions of Fe-C dosage 55.72 g/L, H{sub 2}O{sub 2} concentration 12.32 mL/L and initial pH 3.12. Three-dimensional excitation and emission matrix (3D-EEM) fluorescence spectroscopy and molecular weight (MW) distribution demonstrated that high molecular weight fractions such as refractory fulvic-like substances in leachate were effectively destroyed during the combined processes, which should be attributed to the combination oxidative effect of microelectrolysis and Fenton. The fixed-bed column experiments were performed and the breakthrough curves at different flow rates were evaluated to determine the practical applicability of the combined process. All these results show that the hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor is a promising and efficient technology for the treatment of mature landfill leachate.

  2. Winery wastewater treatment by a combined process: long term aerated storage and Fenton's reagent.

    Science.gov (United States)

    Lucas, Marco S; Mouta, Maria; Pirra, António; Peres, José A

    2009-01-01

    The degradation of the organic pollutants present in winery wastewater was carried out by the combination of two successive steps: an aerobic biological process followed by a chemical oxidation process using Fenton's reagent. The main goal of this study was to evaluate the temporal characteristics of solids and chemical oxygen demand (COD) present in winery wastewater in a long term aerated storage bioreactor. The performance of different air dosage daily supplied to the biologic reactor, in laboratory and pilot scale, were examined. The long term hydraulic retention time, 11 weeks, contributed remarkably to the reduction of COD (about 90%) and the combination with the Fenton's reagent led to a high overall COD reduction that reached 99.5% when the mass ratio (R = H(2)O(2)/COD) used was equal to 2.5, maintaining constant the molar ratio H(2)O(2)/Fe(2+)=15.

  3. Heterogeneous photo-Fenton oxidation with natural clays for phenol and tyrosol remediation

    Directory of Open Access Journals (Sweden)

    Djeffal L.

    2013-09-01

    Full Text Available Due to their excellent properties, clays have been widely used in several applications, particularly in catalysis. In this paper, three clays were used as heterogeneous photo-Fenton catalysts for phenol and tyrosol oxidations. Particular attention was given to the effect of the main operating conditions on the process performance. A total conversion was obtained for both organic pollutants with studied catalysts in 20 minutes reaction. For phenol, a total organic carbon (TOC conversion of 93% was obtained using sieved and calcined smectite clay. The TOC conversion was 60% for tyrosol with the same catalyst. Clays were characterized by chemical analysis, BET, XRD, TPR and SEM.

  4. Combined treatment of retting flax wastewater using Fenton oxidation and granular activated carbon

    Directory of Open Access Journals (Sweden)

    Sohair I. Abou-Elela

    2016-07-01

    Full Text Available The process of retting flax produces a huge amount of wastewater which is characterized with bad unpleasant smell and high concentration of organic materials. Treatment of such waste had always been difficult because of the presence of refractory organic pollutants such as lignin. In this study, treatment of retting wastewater was carried out using combined system of Fenton oxidation process followed by adsorption on granular activated carbon (GAC. The effects of operating condition on Fenton oxidation process such as hydrogen peroxide and iron concentration were investigated. In addition, kinetic study of the adsorption process was elaborated. The obtained results indicated that degradation of organic matters follows a pseudo-first order reaction with regression coefficient of 0.98. The kinetic model suggested that the rate of reaction was highly affected by the concentration of hydrogen peroxide. Moreover, the results indicated that the treatment module was very efficient in removing the organic and inorganic pollutants. The average percentage removal of chemical oxygen demand (COD, total suspended solid (TSS, oil, and grease was 98.60%, 86.60%, and 94.22% with residual values of 44, 20, and 5 mg/L, respectively. The treated effluent was complying with the National Regulatory Standards for wastewater discharge into surface water or reuse in the retting process.

  5. Degradation of trans-ferulic acid in acidic aqueous medium by anodic oxidation, electro-Fenton and photoelectro-Fenton

    Energy Technology Data Exchange (ETDEWEB)

    Flores, Nelly; Sirés, Ignasi; Garrido, José Antonio; Centellas, Francesc; Rodríguez, Rosa María; Cabot, Pere Lluís; Brillas, Enric, E-mail: brillas@ub.edu

    2016-12-05

    Highlights: • trans-Ferulic acid degradation by EAOPs using a stirred BDD/air-diffusion cell. • Slow substrate abatement and poor mineralization by AO-H{sub 2}O{sub 2}. • 98% Mineralization by PEF, but with rapid and similar substrate decay than by EF. • Quicker degradation by SPEF due to the more potent photolytic action of sunlight. • Reaction pathway with four primary aromatic products and three final carboxylic acids. - Abstract: Solutions of pH 3.0 containing trans-ferulic acid, a phenolic compound in olive oil mill wastewater, have been comparatively degraded by anodic oxidation with electrogenerated H{sub 2}O{sub 2} (AO-H{sub 2}O{sub 2}), electro-Fenton (EF) and photoelectro-Fenton (PEF). Trials were performed with a BDD/air-diffusion cell, where oxidizing ·OH was produced from water discharge at the BDD anode and/or in the solution bulk from Fenton’s reaction between cathodically generated H{sub 2}O{sub 2} and added catalytic Fe{sup 2+}. The substrate was very slowly removed by AO-H{sub 2}O{sub 2}, whereas it was very rapidly abated by EF and PEF, at similar rate in both cases, due to its fast reaction with ·OH in the bulk. The AO-H{sub 2}O{sub 2} process yielded a slightly lower mineralization than EF, which promoted the accumulation of barely oxidizable products like Fe(III) complexes. In contrast, the fast photolysis of these latter species under irradiation with UVA light in PEF led to an almost total mineralization with 98% total organic carbon decay. The effect of current density and substrate concentration on the performance of all treatments was examined. Several solar PEF (SPEF) trials showed its viability for the treatment of wastewater containing trans-ferulic acid at larger scale. Four primary aromatic products were identified by GC–MS analysis of electrolyzed solutions, and final carboxylic acids like fumaric, acetic and oxalic were detected by ion-exclusion HPLC. A reaction sequence for trans-ferulic acid mineralization

  6. Natural soil mediated photo Fenton-like processes in treatment of pharmaceuticals: Batch and continuous approach.

    Science.gov (United States)

    Changotra, Rahil; Rajput, Himadri; Dhir, Amit

    2017-12-01

    This paper manifests the potential viability of soil as a cost-free catalyst in photo-Fenton-like processes for treating pharmaceuticals at large scale. Naturally available soil without any cost intensive modification was utilized as a catalyst to degrade pharmaceuticals, specifically ornidazole (ORZ) and ofloxacin (OFX). Soil was characterized and found enriched with various iron oxides like hematite, magnetite, goethite, pyrite and wustite, which contributes toward enhanced dissolution of Fe 3+ than Fe 2+ in the aqueous solution resulting in augmented rate of photo-Fenton reaction. The leached iron concentration in solution was detected during the course of experiments. The degradation of ORZ and OFX was assessed in solar induced batch experiments using H 2 O 2 as oxidant and 95% ORZ and 92% OFX removal was achieved. Elevated efficiencies were achieved due to Fe 2+ /Fe 3+ cycling, producing more hydroxyl radical leading to the existence of homogeneous and heterogeneous reactions simultaneously. The removal efficiency of solar photo-Fenton like process was also compared to photo-Fenton process with different irradiation sources (UV-A and UV-B) and were statistically analysed. Continuous-scale studies were conducted employing soil either in the form of soil beads or as a thin layer spread on the surface of baffled reactor. Soil beads were found to have satisfactory reusability and stability. 84 and 79% degradation of ORZ and OFX was achieved using soil as thin layer while with soil beads 71 and 68% degradation, respectively. HPLC and TOC study confirmed the efficient removal of both the compounds. Toxicity assessment demonstrates the inexistence of toxic intermediates during the reaction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Mineralization of herbicide 3,6-dichloro-2-methoxybenzoic acid in aqueous medium by anodic oxidation, electro-Fenton and photoelectro-Fenton

    International Nuclear Information System (INIS)

    Brillas, Enric; Banos, Miguel Angel; Garrido, Jose Antonio

    2003-01-01

    The mineralization of acidic aqueous solutions with 230 and 115 ppm of herbicide 3,6-dichloro-2-methoxybenzoic acid (dicamba) in 0.05 M Na 2 SO 4 of pH 3.0 has been studied by electro-Fenton and photoelectro-Fenton using a Pt anode and an O 2 -diffusion cathode, where oxidizing hydroxyl radicals are produced from Fenton's reaction between added Fe 2+ and H 2 O 2 generated by the cathode. While electro-Fenton only yields 60-70% mineralization, photoelectro-Fenton allows a fast and complete depollution of herbicide solutions, even at low currents, by the action of UV irradiation. In both treatments, the initial chlorine is rapidly released to the medium as chloride ion. Comparative electrolyses by anodic oxidation in the absence and presence of electrogenerated H 2 O 2 give very poor degradation. The dicamba decay follows a pseudo-first-order reaction, as determined by reverse-phase chromatography. Formic, maleic and oxalic acids have been detected in the electrolyzed solutions by ion-exclusion chromatography. In electro-Fenton, all formic acid is transformed into CO 2 , and maleic acid is completely converted into oxalic acid, remaining stable Fe 3+ -oxalato complexes in the solution. The fast mineralization of such complexes by UV light explains the highest oxidative ability of photoelectro-Fenton

  8. Treatment of amoxicillin by O3/Fenton process in a rotating packed bed.

    Science.gov (United States)

    Li, Mo; Zeng, Zequan; Li, Yingwen; Arowo, Moses; Chen, Jianfeng; Meng, Hong; Shao, Lei

    2015-03-01

    In this study, simulated amoxicillin wastewater was treated by the O3/Fenton process in a rotating packed bed (RPB) and the results were compared with the Fenton process and the O3 followed by Fenton (O3 + Fenton) process. The chemical oxygen demand (COD) removal rate and the ratio of 5-day biological oxygen demand to chemical oxygen demand (BOD5/COD) in the O3/Fenton process were approximately 17% and 26%, respectively, higher than those in the O3 + Fenton process with an initial pH of 3. The COD removal rate of the amoxicillin solution reached maximum at the Fe(II) concentration of 0.6 mM, temperature of 25 °C, rotation speed of 800 rpm and initial pH of 3. The BOD5/COD of the amoxicillin solution increased from 0 to 0.38 after the solution was treated by the O3/Fenton process. Analysis of the intermediates indicated that the pathway of amoxicillin degradation in the O3/Fenton process was similar to that in the O3 + Fenton process. Contrast experiment results showed that amoxicillin degradation was significantly intensified in the RPB. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Advanced landfill leachate treatment using iron-carbon microelectrolysis- Fenton process: Process optimization and column experiments.

    Science.gov (United States)

    Wang, Liqun; Yang, Qi; Wang, Dongbo; Li, Xiaoming; Zeng, Guangming; Li, Zhijun; Deng, Yongchao; Liu, Jun; Yi, Kaixin

    2016-11-15

    A novel hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor was proposed for the pretreatment of mature landfill leachate. This reactor, combining microelectrolysis with Fenton process, revealed high treatment efficiency. The operating variables, including Fe-C dosage, H2O2 concentration and initial pH, were optimized by the response surface methodology (RSM), regarding the chemical oxygen demand (COD) removal efficiency and biochemical oxygen demand: chemical oxygen demand (BOD5/COD) as the responses. The highest COD removal (74.59%) and BOD5/COD (0.50) was obtained at optimal conditions of Fe-C dosage 55.72g/L, H2O2 concentration 12.32mL/L and initial pH 3.12. Three-dimensional excitation and emission matrix (3D-EEM) fluorescence spectroscopy and molecular weight (MW) distribution demonstrated that high molecular weight fractions such as refractory fulvic-like substances in leachate were effectively destroyed during the combined processes, which should be attributed to the combination oxidative effect of microelectrolysis and Fenton. The fixed-bed column experiments were performed and the breakthrough curves at different flow rates were evaluated to determine the practical applicability of the combined process. All these results show that the hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor is a promising and efficient technology for the treatment of mature landfill leachate. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Improving degradation of paracetamol by integrating gamma radiation and Fenton processes.

    Science.gov (United States)

    Cruz-González, Germán; Rivas-Ortiz, Iram B; González-Labrada, Katia; Rapado-Paneque, Manuel; Chávez-Ardanza, Armando; Nuevas-Paz, Lauro; Jáuregui-Haza, Ulises J

    2016-10-14

    Degradation of paracetamol (N-(4-hydroxiphenyl)acetamide) in aqueous solution by gamma radiation, gamma radiation/H2O2 and gamma radiation/Fenton processes was studied. Parameters affecting the radiolysis of paracetamol such as radiation dose, initial concentration of pollutant, pH and initial oxidant concentration were investigated. Gamma radiation was performed using a (60)Co source irradiator. Paracetamol degradation and mineralization increased with increasing absorbed radiation dose, but decreased with increasing initial concentration of the drug in aqueous solution. The addition of H2O2 resulted in an increased effect on irradiation-driven paracetamol degradation in comparison with the performance of the irradiation-driven process alone: paracetamol removal increased from 48.9% in the absence of H2O2 to 95.2% for H2O2 concentration of 41.7 mmol/L. However, the best results were obtained with gamma radiation/Fenton process with 100% of the drug removal at 5 kGy, for optimal H2O2 and Fe(2+) concentrations at 13.9 and 2.3 mmol/L, respectively, with a high mineralization of 63.7%. These results suggest gamma radiation/H2O2 and gamma radiation/Fenton processes as promising methods for paracetamol degradation in polluted wastewaters.

  11. The oxidative response and viable reaction mechanism of the textile dyes by fenton reagent

    International Nuclear Information System (INIS)

    Masooda, Q.; Hijira, T.; Sitara, M.; Sehar, M.; Sundus, A.; Mohsin, A.

    2017-01-01

    The mechanism of the degradation of the Reactive Red 239 and Reactive Blue 19 by Fenton reagent was studied by advanced oxidation process in aqueous medium. The spectroscopic technique was adopted for the measurements of dye concentration. Moreover they were determined at 540 nm and 590 nm, respectively. Kinetics of the reaction was studied under the effect of concentration of reactive dyes, concentration of oxidant were followed under pseudo first order condition and found to influence the catalytic mechanism. The pH of the medium, vibrant response of several cations and anions and influence of ionic strength on the reaction kinetics were also monitored. Physical evidences for the degradation and mineralization of the dyes were evaluated by Lime water test, Ring Test and TLC test also confirmed the degradation of dye. Inhibitory effects of dyes were observed by CO3-, HCO3-, HPO42-, Cl-, I- Al3+ and Na+. Thermodynamic activation parameters in the oxidation reaction were studied and mode of mechanism was suggested on the basic of these parameters. This study explored the safe and eco friendly degradation of the textile dyes under Pseudo first order rate constant. It was observed that Fenton assisted degradation of the dyes under controlled conditions was found to be favorable for the treatment of textile wastewater. Moreover compared to other chemical methods it is effective and harmless to the environment. (author)

  12. Photo-Fenton and Fenton-like processes for the treatment of the antineoplastic drug 5-fluorouracil under simulated solar radiation.

    Science.gov (United States)

    Koltsakidou, Α; Antonopoulou, M; Sykiotou, M; Εvgenidou, Ε; Konstantinou, I; Lambropoulou, D A

    2017-02-01

    In the present study, photo-Fenton and Fenton-like processes were investigated for the degradation and mineralization of the antineoplastic drug 5-fluorouracil (5-FU). For the optimization of photo-Fenton treatment under simulated solar light (SSL) radiation, the effects of several operating parameters (i.e., 5-FU concentration, Fe 3+ , and oxidant concentration) on the treatment efficiency were studied. According to the results, SSL/[Fe(C 2 Ο 4 ) 3 ] 3- /Η 2 Ο 2 process was the most efficient, since faster degradation of 5-FU and higher mineralization percentages were achieved. All the applied processes followed quite similar transformation routes which include defluorination-hydroxylation as well as pyrimidine ring opening, as demonstrated by the transformation products identified by high resolution mass spectrometry analysis. The toxicity of the treated solutions was evaluated using the Microtox assay. In general, low toxicity was recorded for the initial solution and the solution at the end of the photocatalytic treatment, while an increase in the overall toxicity was observed only at the first stages of SSL/Fe 3+ /Η 2 Ο 2 and SSL/Fe 3+ /S 2 O 8 2- processes.

  13. Decontamination of unsymmetrical dimethylhydrazine waste water by hydrodynamic cavitation-induced advanced Fenton process.

    Science.gov (United States)

    Torabi Angaji, Mahmood; Ghiaee, Reza

    2015-03-01

    A pilot scale hydrodynamic cavitation (HC) reactor, using iron metal blades, as the heterogeneous catalyst, with no external source of H₂O₂ was developed for catalytic decontamination of unsymmetrical dimethylhydrazine (UDMH) waste water. In situ generation of Fenton reagents suggested an induced advanced Fenton process (IAFP) to explain the enhancing effect of the used catalyst in the HC process. The effects of the applied catalyst, pH of the initial solution (1.0-9.7), initial UDMH concentration (2-15 mg/l), inlet pressure (5.5-7.8bar), and downstream pressure (2-6 bar), have been investigated. The results showed that the highest cavitation yield can be obtained at pH 3 and initial UDMH concentration of 10mg/l. Also, an increase in the inlet pressure would lead to an increase in the extent of UDMH degradation. In addition, the optimum value of 3 bar was determined for the downstream pressure that resulted to 98.6% degradation of UDMH after 120 min of processing time. Neither n-nitrosodimethylamine (NDMA) nor any other toxic byproduct (/end-product) was observed in the investigated samples. Formic acid and acetic acid, as well as nitromethane, were identified as oxidation by-products. The present work has conclusively established that hydrodynamic cavitation in combination with Fenton's chemistry can be effectively used for the degradation of UDMH. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Evaluation of adsorption and Fenton-adsorption processes for landfill leachate treatment

    OpenAIRE

    San Pedro-Cedillo, L.; Méndez-Novelo, R.I.; Rojas-Valencia, M.N.; Barceló-Quintal, M.; Castillo-Borges, E.R.; Sauri-Riancho, M.R.; Marrufo-Gómez, J.M.

    2015-01-01

    The objective of this research was to compare the adsorption and Fenton-adsorption treatments for the removal of contaminants in leachate from landfills and thus determine the most efficient one. The adsorption process with granular activated carbon was tested in two types of samples: raw leachate and leachate treated by Fenton. The results showed color, chemical oxygen demand (COD), total nitrogen and total organic carbon (TOC) removal rates higher than 99% through the Fenton-adsorption proc...

  15. Electro-Fenton and photoelectro-Fenton degradations of the drug beta-blocker propranolol using a Pt anode: Identification and evolution of oxidation products

    Energy Technology Data Exchange (ETDEWEB)

    Isarain-Chavez, Eloy; Cabot, Pere Lluis; Centellas, Francesc; Rodriguez, Rosa Maria; Arias, Conchita; Garrido, Jose Antonio [Laboratori d' Electroquimica dels Materials i del Medi Ambient, Departament de Quimica Fisica, Facultat de Quimica, Universitat de Barcelona, Marti i Franques 1-11, 08028 Barcelona (Spain); Brillas, Enric, E-mail: brillas@ub.edu [Laboratori d' Electroquimica dels Materials i del Medi Ambient, Departament de Quimica Fisica, Facultat de Quimica, Universitat de Barcelona, Marti i Franques 1-11, 08028 Barcelona (Spain)

    2011-01-30

    The beta-blocker propranolol hydrochloride has been degraded by electrochemical advanced oxidation processes like electro-Fenton (EF) and photoelectro-Fenton (PEF) using a single cell with a Pt anode and an air diffusion cathode (ADE) for H{sub 2}O{sub 2} electrogeneration and a combined system containing the above Pt/ADE pair coupled in parallel to a Pt/carbon-felt (CF) cell. Organics are mainly oxidized with hydroxyl radical ({center_dot}OH) formed from Fenton's reaction between added Fe{sup 2+} and electrogenerated H{sub 2}O{sub 2}. The PEF treatment in Pt/ADE-Pt/CF system yields almost total mineralization because {center_dot}OH production is enhanced by Fe{sup 2+} regeneration from Fe{sup 3+} reduction at the CF cathode and Fe(III) complexes with generated carboxylic acids are rapidly photodecarboxylated under UVA irradiation. Lower mineralization degree is found for PEF in Pt/ADE cell due to the little influence of UVA light on Fe{sup 2+} regeneration. The homologous EF processes are much less potent as a result of the persistence of Fe(III)-carboxylate complexes. Aromatic intermediates such as 1-naphthol, 1,4-naphthoquinone and phthalic acid and generated carboxylic acids such as pyruvic, glycolic, malonic, maleic, oxamic, oxalic and formic are identified. While chloride ion remains stable, NH{sub 4}{sup +} and NO{sub 3}{sup -} ions are released to the medium. A reaction sequence for propranolol hydrochloride mineralization is proposed.

  16. Decolorization of Diazo Dye Ponceau S by Fenton Process

    Directory of Open Access Journals (Sweden)

    Muhammad Muslim

    2013-12-01

    Full Text Available An attempt has been taken to decolorize and mineralize Ponceau S (PS, a diazo dye, in aqueous solution by Fenton process. Effects of solution pH, concentrations of H2O2, Fe(II and PS on the decolorization of PS have also been studied through batch experiments. About 90% decolorization was found under the optimal conditions [PS]: [H2O2]: [Fe(II] = 1:12:2 and [H2O2]/[Fe(II] = 6 at pH 2.85 in 40 minutes. The overall results revealed that mineralization was rather slower as compared with the decolorization.

  17. Enhancement of Fenton oxidation for removing organic matter from hypersaline solution by accelerating ferric system with hydroxylamine hydrochloride and benzoquinone.

    Science.gov (United States)

    Peng, Siwei; Zhang, Weijun; He, Jie; Yang, Xiaofang; Wang, Dongsheng; Zeng, Guisheng

    2016-03-01

    Fenton oxidation is generally inhibited in the presence of a high concentration of chloride ions. This study investigated the feasibility of using benzoquinone (BQ) and hydroxylamine hydrochloride (HA) as Fenton enhancers for the removal of glycerin from saline water under ambient temperature by accelerating the ferric system. It was found that organics removal was not obviously affected by chloride ions of low concentration (less than 0.1mol/L), while the mineralization rate was strongly inhibited in the presence of a large amount of chloride ions. In addition, ferric hydrolysis-precipitation was significantly alleviated in the presence of HA and BQ, and HA was more effective in reducing ferric ions into ferrous ions than HA, while the H2O2 decomposition rate was higher in the BQ-Fenton system. Electron spin resonance analysis revealed that OH production was reduced in high salinity conditions, while it was enhanced after the addition of HA and BQ (especially HA). This study provided a possible solution to control and alleviate the inhibitory effect of chloride ions on the Fenton process for organics removal. Copyright © 2015. Published by Elsevier B.V.

  18. Improvement of biodegradability of oil wastewater contained PAM by pretreatment with Fenton oxidation

    International Nuclear Information System (INIS)

    Bao, M.; Wang, N.

    2008-01-01

    The use of polymer flooding in enhanced oil recovery operations has resulted in higher levels of polyacrylamide (PAM) found in oil wastewater. PAM is harmful to the environment, particularly the monomer acrylamide that is generated from PAM degradation. In this study, PAM derived from oil wastewater was pretreated by Fenton oxidation. This oxidation method is based on the use of a mixture of H 2 O 2 and iron salts which produce hydroxyl radicals in acidic conditions. The method offers a cost-effective source of hydroxyl radicals, using easy-to-handle reagents. The purpose of this study was to transform PAM to biodegradable intermediums. The optimal conditions for the Fenton reactions were also determined and described. Under optimal conditions, the removal ratios of PAM and chemical oxygen demand (COD) were 83.8 and 77 per cent respectively. It was concluded that Fenton's oxidation is an effective treatment to improved the biodegradability of PAM. 14 refs., 1 tab., 7 figs

  19. A highly energy-efficient flow-through electro-Fenton process for organic pollutants degradation

    International Nuclear Information System (INIS)

    Ma, Liang; Zhou, Minghua; Ren, Gengbo; Yang, Weilu; Liang, Liang

    2016-01-01

    Highlights: • A highly energy-efficient flow-through electro-Fenton reactor was designed. • It had high H 2 O 2 yield and low energy consumption for organic pollutants degradation. • The effect of operational parameters was optimized and possible process mechanism was studied. • The novel system performed wide practicability and potential for organic pollutants degradation. - Abstract: A highly energy-efficient flow-through Electro-Fenton (E-Fenton) reactor for oxidation of methylene blue (MB) from aqueous solution was designed using a perforated DSA as anode and the graphite felt modified by carbon black and polytetrafluoroethylene (PTFE) as cathode for the in situ generation of H 2 O 2 . The modified cathode had a high H 2 O 2 production with low energy consumption, which was characterized by scanning electron microscopy (SEM), nitrogen adsorption-desorption study and contact angle. The flow-through E-Fenton system was compared to the flow-by and regular one, and confirmed to be best on MB removal and TOC degradation. The operational parameters such as current density, pH, Fe 2+ concentration and flow rate were optimized. The MB and TOC removal efficiency of the effluents could keep above 90% and 50%, respectively, and the energy consumption was 23.0 kWh/kgTOC at the current density of 50 mA, pH 3, 0.3 mM Fe 2+ , and the flow rate of 7 mL/min. ·OH was proved to be the main oxidizing species in this system. After 5 times operation, the system, especially cathode, still showed good stability. Five more organic pollutants including orange II (OG), tartrazine, acetylsalicylic acid (ASA), tetracycline (TC) and 2,4-dichlorophen (2,4-DCP) were investigated and the electric energy consumption (EEC) was compared with literatures. All results demonstrated that this flow-through E-Fenton system was energy-efficient and potential for degradation of organic pollutants.

  20. Influence of ultrasonication and Fenton oxidation pre-treatment on rheological characteristics of wastewater sludge.

    Science.gov (United States)

    Pham, T T H; Brar, S K; Tyagi, R D; Surampalli, R Y

    2010-01-01

    The effect of ultrasonication and Fenton oxidation as physico-chemical pre-treatment processes on the change of rheology of wastewater sludge was investigated in this study. Pre-treated and raw sludges displayed non-Newtonian rheological behaviour with shear thinning as well as thixotropic properties for total solids ranging from 10 g/L to 40 g/L. The rheological models, namely, Bingham plastic, Casson law, NCA/CMA Casson, IPC Paste, and power law were also studied to characterize flow of raw and pre-treated sludges. Among all rheological models, the power law was more prominent in describing the rheology of the sludges. Pre-treatment processes resulted in a decrease in pseudoplasticity of sludge due to the decrease in consistency index K varying from 42.4 to 1188, 25.6 to 620.4 and 52.5 to 317.9; and increase in flow behaviour index n changing from 0.5 to 0.35, 0.62 to 0.55 and 0.63 to 0.58, for RS, UlS and FS, respectively at solids concentration 10-40 g/L. The correlation between improvement of biodegradability and dewaterability, decrease in viscosity, and change in particle size as a function of sludge pre-treatment process was also investigated. Fenton oxidation facilitated sludge filterability resulting in capillary suction time values which were approximately 50% of the raw sludges, whereas ultrasonication with high input energy deteriorated the filterability. Biodegradability was also enhanced by the pre-treatment processes and the maximum value was obtained (64%, 77% and 73% for raw, ultrasonicated and Fenton oxidized sludges, respectively) at total solids concentration of 25 g/L. Hence, pre-treatment of wastewater sludge modified the rheological properties so that: (1) the flowability of sludge was improved for transport through the treatment train (via pipes and pumps); (2) the dewaterability of wastewater sludge was enhanced for eventual disposal and; (3) the assimilation of nutrients by microorganisms for further value-addition was increased.

  1. Removal of organic pollutants from industrial wastewater by applying photo-Fenton oxidation technology

    Directory of Open Access Journals (Sweden)

    Ebrahiem E. Ebrahiem

    2017-05-01

    Full Text Available The general strategy of this study was based on evaluation of the possibility of applying advanced photo-oxidation technique (Fenton oxidation process for removal of the residuals organic pollutants present in cosmetic wastewater. The different parameters that affect the chemical oxidation process for dyes in their aqueous solutions were studied by using Fenton’s reaction. These parameters are pH, hydrogen peroxide (H2O2 dose, ferrous sulfate (FeSO4·7H2O dose, Initial dye concentration, and time. The optimum conditions were found to be: pH 3, the dose of 1 ml/l H2O2 and 0.75 g/l for Fe(II and Fe(III and reaction time 40 min. Finally, chemical oxygen demands (COD, before and after oxidation process was measured to ensure the entire destruction of organic dyes during their removal from wastewater. The experimental results show that Fenton’s oxidation process successfully achieved very good removal efficiency over 95%.

  2. Application of Acid Cracking and Fenton Processes inTreating Olive Mill Wastewater

    Directory of Open Access Journals (Sweden)

    Majid Aliabadi

    2006-03-01

    Full Text Available In recent years, the growth in the industries of olive oil extraction has brought about a number of environmental problems. The waste water resulting from olive oil extraction can not be naturally degraded due to the presence of phenol, volatile fatty acids, catchin, and other recalcitrants.In recent years advanced oxidation processes based on hydroxyl radical are paid special attention by scientific, research and industrial centers to degrade the pollutants. In this study, a combination of acid cracking and advanced oxidation process in terms of Fenton process have been studied. Results showed that acid cracking can remove 97, 47, 30, 63 and 57 percent of Turbidity, COD, Total Phenols, Color and Aromaticity, respectively. Fenton process in pH=3 at optimal conditions can remove 57, 97, 18 and 32 percent of COD, Total Phenols, Color and Aromaticity, respectively. Necessary time of reaction was 4 hrs and optimum concentration of H2O2 and Fe2+ ions was determined 0. 5 M and 0.02 M, respectively. Increasing temperature in the range of 25-35°C and type of iron used(ferric or ferrous has no considerable effect in  the efficiency of the process.

  3. Optimization of Fenton oxidation for the removal of methyl parathion in aqueous solution

    Directory of Open Access Journals (Sweden)

    Roli Saini

    2016-09-01

    Full Text Available In the present study, for the treatment of methyl parathion, Fenton oxidation is adopted. The aims of this study were (a to assess the removal efficiency in terms of chemical oxygen demand (COD, (b to scrutinize the influence of different parameters: initial pH, concentrations of H2O2 and Fe2+ and, (c response surface methodology (RSM was used to design the Fenton process. Three-level central composite design (CCD was applied in designing the experiments to observe the effects of most important operating factors. The enactment of the model was judged with the analysis of variance (ANOVA. A quadratic model was used to represent the experimental data. The predicted values and experimental values were found to be in good agreement with the (R2 = 0.9891 and Adj-R2 = 0.9877, which define the propriety of the model. The characteristic of methyl parathion bearing wastewater was concentration 30 mg/L, COD 440 mg/L, pH 6.5. Maximum removal efficiency was perceived at acidic pH value 3.

  4. Improvement of COD and color removal from UASB treated poultry manure wastewater using Fenton's oxidation

    International Nuclear Information System (INIS)

    Yetilmezsoy, Kaan; Sakar, Suleyman

    2008-01-01

    The applicability of Fenton's oxidation as an advanced treatment for chemical oxygen demand (COD) and color removal from anaerobically treated poultry manure wastewater was investigated. The raw poultry manure wastewater, having a pH of 7.30 (±0.2) and a total COD of 12,100 (±910) mg/L was first treated in a 15.7 L of pilot-scale up-flow anaerobic sludge blanket (UASB) reactor. The UASB reactor was operated for 72 days at mesophilic conditions (32 ± 2 deg. C) in a temperature-controlled environment with three different hydraulic retention times (HRT) of 15.7, 12 and 8.0 days, and with organic loading rates (OLR) between 0.650 and 1.783 kg COD/(m 3 day). Under 8.0 days of HRT, the UASB process showed a remarkable performance on total COD removal with a treatment efficiency of 90.7% at the day of 63. The anaerobically treated poultry manure wastewater was further treated by Fenton's oxidation process using Fe 2+ and H 2 O 2 solutions. Batch tests were conducted on the UASB effluent samples to determine the optimum operating conditions including initial pH, effects of H 2 O 2 and Fe 2+ dosages, and the ratio of H 2 O 2 /Fe 2+ . Preliminary tests conducted with the dosages of 100 mg Fe 2+ /L and 200 mg H 2 O 2 /L showed that optimal initial pH was 3.0 for both COD and color removal from the UASB effluent. On the basis of preliminary test results, effects of increasing dosages of Fe 2+ and H 2 O 2 were investigated. Under the condition of 400 mg Fe 2+ /L and 200 mg H 2 O 2 /L, removal efficiencies of residual COD and color were 88.7% and 80.9%, respectively. Under the subsequent condition of 100 mg Fe 2+ /L and 1200 mg H 2 O 2 /L, 95% of residual COD and 95.7% of residual color were removed from the UASB effluent. Results of this experimental study obviously indicated that nearly 99.3% of COD of raw poultry manure wastewater could be effectively removed by a UASB process followed by Fenton's oxidation technology used as a post-treatment unit

  5. Improvement of COD and color removal from UASB treated poultry manure wastewater using Fenton's oxidation.

    Science.gov (United States)

    Yetilmezsoy, Kaan; Sakar, Suleyman

    2008-03-01

    The applicability of Fenton's oxidation as an advanced treatment for chemical oxygen demand (COD) and color removal from anaerobically treated poultry manure wastewater was investigated. The raw poultry manure wastewater, having a pH of 7.30 (+/-0.2) and a total COD of 12,100 (+/-910) mg/L was first treated in a 15.7 L of pilot-scale up-flow anaerobic sludge blanket (UASB) reactor. The UASB reactor was operated for 72 days at mesophilic conditions (32+/-2 degrees C) in a temperature-controlled environment with three different hydraulic retention times (HRT) of 15.7, 12 and 8.0 days, and with organic loading rates (OLR) between 0.650 and 1.783 kg COD/(m3day). Under 8.0 days of HRT, the UASB process showed a remarkable performance on total COD removal with a treatment efficiency of 90.7% at the day of 63. The anaerobically treated poultry manure wastewater was further treated by Fenton's oxidation process using Fe2+ and H2O2 solutions. Batch tests were conducted on the UASB effluent samples to determine the optimum operating conditions including initial pH, effects of H2O2 and Fe2+ dosages, and the ratio of H2O2/Fe2+. Preliminary tests conducted with the dosages of 100 mg Fe2+/L and 200 mg H2O2/L showed that optimal initial pH was 3.0 for both COD and color removal from the UASB effluent. On the basis of preliminary test results, effects of increasing dosages of Fe2+ and H2O2 were investigated. Under the condition of 400 mg Fe2+/L and 200 mg H2O2/L, removal efficiencies of residual COD and color were 88.7% and 80.9%, respectively. Under the subsequent condition of 100 mg Fe2+/L and 1200 mg H2O2/L, 95% of residual COD and 95.7% of residual color were removed from the UASB effluent. Results of this experimental study obviously indicated that nearly 99.3% of COD of raw poultry manure wastewater could be effectively removed by a UASB process followed by Fenton's oxidation technology used as a post-treatment unit.

  6. Design of a visible light driven photo-electrochemical/electro-Fenton coupling oxidation system for wastewater treatment

    International Nuclear Information System (INIS)

    Ding, Xing; Ai, Zhihui; Zhang, Lizhi

    2012-01-01

    Highlights: ► Coupling PEC and EF oxidation significantly improves pollutant degradation efficiency. ► The degradation of the PEC/EF system was increased by 154%. ► The instantaneous current efficiency of the PEC/EF system was increased by 26%. - Abstract: In this study, we report on a photo-electrochemical/electro-Fenton oxidation (PEC/EF) system by coupling visible light driven photo-electrochemical oxidation (PEC) and electro-Fenton oxidation (EF) in an undivided cell. Bi 2 WO 6 nanoplates deposited on FTO glass (Bi 2 WO 6 /FTO) and Fe-Fe 2 O 3 core–shell nanowires supported on activated carbon fiber (Fe-Fe 2 O 3 /ACF) were used as the anode and the cathode in the PEC/EF system, respectively. This novel PEC/EF system showed much higher activity than the single PEC and EF systems on degradation of rhodamine B in aqueous solution at natural pH. Moreover, the degradation and the instantaneous current efficiencies of the PEC/EF system were increased by 154% and 26% in comparison with the sum of those of single PEC and EF systems, respectively. These significant enhancements could be attributed to the synergetic effect from better separation of photo-generated carriers in the photo-anode and the transfer of photo-electrons to the oxygen diffusion cathode to generate more electro-generated H 2 O 2 and hydroxyl radicals on the Fenton cathode. The better separation of photo-generated carriers contribute more to the overall degradation enhancement than the photo-electrons generated H 2 O 2 and the subsequent Fenton reaction on the cathode during the PEC/EF process.

  7. Combining micelle-clay sorption to solar photo-Fenton processes for domestic wastewater treatment.

    Science.gov (United States)

    Brienza, Monica; Nir, Shlomo; Plantard, Gael; Goetz, Vincent; Chiron, Serge

    2018-06-08

    A tertiary treatment of effluent from a biological domestic wastewater treatment plant was tested by combining filtration and solar photocatalysis. Adsorption was carried out by a sequence of two column filters, the first one filled with granular activated carbon (GAC) and the second one with granulated nano-composite of micelle-montmorillonite mixed with sand (20:100, w/w). The applied solar advanced oxidation process was homogeneous photo-Fenton photocatalysis using peroxymonosulfate (PMS) as oxidant agent. This combination of simple, robust, and low-cost technologies aimed to ensure water disinfection and emerging contaminants (ECs, mainly pharmaceuticals) removal. The filtration step showed good performances in removing dissolved organic matter and practically removing all bacteria such as Escherichia coli and Enterococcus faecalis from the secondary treated water. Solar advanced oxidation processes were efficient in elimination of trace levels of ECs. The final effluent presented an improved sanitary level with acceptable chemical and biological characteristics for irrigation.

  8. Coupling Fenton and biological oxidation for the removal of nitrochlorinated herbicides from water.

    Science.gov (United States)

    Sanchis, S; Polo, A M; Tobajas, M; Rodriguez, J J; Mohedano, A F

    2014-02-01

    The combination of Fenton and biological oxidation for the removal of the nitrochlorinated herbicides alachlor, atrazine and diuron in aqueous solution has been studied. The H2O2 dose was varied from 20 to 100% of the stoichiometric amount related to the initial chemical oxygen demand (COD). The effluents from Fenton oxidation were analyzed for ecotoxicity, biodegradability, total organic carbon (TOC), COD and intermediate byproducts. The chemical step resulted in a significant improvement of the biodegradability in spite of its negligible or even slightly negative effect on the ecotoxicity. Working at 60% of the stoichiometric H2O2 dose allowed obtaining highly biodegradable effluents in the cases of alachlor and atrazine. That dose was even lower (40% of the stoichiometric) for diuron. The subsequent biological treatment was carried out in a sequencing batch reactor (SBR) and the combined Fenton-biological treatment allowed up to around 80% of COD reduction. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Kinetics of imidazolium-based ionic liquids degradation in aqueous solution by Fenton oxidation.

    Science.gov (United States)

    Domínguez, Carmen M; Munoz, Macarena; Quintanilla, Asunción; de Pedro, Zahara M; Casas, Jose A

    2017-10-15

    In the last few years, several works dealing with Fenton oxidation of ionic liquids (ILs) have proved the capability of this technology for their degradation, achieving complete ILs removal and non-toxic effluents. Nevertheless, very little is known about the kinetics of this process, crucial for its potential application. In this work, the effect of several operating conditions, including reaction temperature (50-90 °C), catalyst load (10-50 mg L -1 Fe 3+ ), initial IL concentration (100-2000 mg L -1 ), and hydrogen peroxide dose (10-200% of the stoichiometric amount for the complete IL mineralization) on 1-butyl-3-methylimidazolium chloride ([C 4 mim]Cl) oxidation has been investigated. Under the optimum operating conditions (T = 90 °C; [Fe 3+ ] 0  = 50 mg L -1 ; [H 2 O 2 ] 0  = 100% of the stoichiometric amount), the complete removal of [C 4 mim]Cl (1000 mg L -1 ) was achieved at 1.5-min reaction time. From the experimental results, a potential kinetic model capable to describe the removal of imidazolium-based ILs by Fenton oxidation has been developed. By fitting the proposed model to the experimental data, the orders of the reaction with respect to IL initial concentration, Fe 3+ amount and H 2 O 2 dose were found to be close to 1, with an apparent activation energy of 43.3 kJ mol -1 . The model resulted in a reasonable fit within the wide range of operating conditions tested in this work.

  10. Treatment of hazardous landfill leachate using Fenton process followed by a combined (UASB/DHS) system.

    Science.gov (United States)

    Ismail, Sherif; Tawfik, Ahmed

    2016-01-01

    Fenton process for pre-treatment of hazardous landfill leachate (HLL) was investigated. Total, particulate and soluble chemical oxygen demand (CODt, CODp and CODs) removal efficiency amounted to 67%, 47% and 64%, respectively, at pH value of 3.5, molar ratio (H2O2/Fe(2+)) of 5, H2O2 dosage of 25 ml/L and contact time of 15 min. Various treatment scenarios were attempted and focused on studying the effect of pre-catalytic oxidation process on the performance of up-flow anaerobic sludge blanket (UASB), UASB/down-flow hanging sponge (DHS) and DHS system. The results obtained indicated that pre-catalytic oxidation process improved the CODt removal efficiency in the UASB reactor by a value of 51.4%. Overall removal efficiencies of CODt, CODs and CODp were 80 ± 6%, 80 ± 7% and 78 ± 16% for UASB/DHS treating pre-catalytic oxidation effluent, respectively. The removal efficiencies of CODt, CODs and CODp were, respectively, decreased to 54 ± 2%, 49 ± 2% and 71 ± 16% for UASB/DHS system without pre-treatment. However, the results for the combined process (UASB/DHS) system is almost similar to those obtained for UASB reactor treating pre-catalytic oxidation effluent. The DHS system achieved average removal efficiencies of 52 ± 4% for CODt, 51 ± 4% for CODs and 52 ± 15% for CODp. A higher COD fractions removal was obtained when HLL was pre-treated by Fenton reagent. The combined processes provided a removal efficiency of 85 ± 1% for CODt, 85 ± 1% for CODs and 83 ± 8% for CODp. The DHS system is not only effective for organics degradation but also for ammonia oxidation. Almost complete ammonia (NH4-N) removal (92 ± 3.6%) was occurred and the nitrate production amounted to 37 ± 6 mg/L in the treated effluent. This study strongly recommends applying Fenton process followed by DHS system for treatment of HLL.

  11. Decolorization of Diazo Dye Ponceau S by Fenton Process

    International Nuclear Information System (INIS)

    Muslim, M.; Habib, M.A.; Islam, T.S.A.; Mahmood, A.J.; Ismail, I.M.I.

    2013-01-01

    An attempt has been taken to decolorize and mineralize Ponceau S (PS), a diazo dye, in aqueous solution by Fenton process. Effects of solution pH, concentrations of H/sub 2/O/sub 2/, Fe(II) and PS on the decolorization of PS have also been studied through batch experiments. About 90percentage decolorization was found under the optimal conditions (PS): (H/sub 2/O/sub 2/): (Fe(II)) = 1:12:2 and (H/sub 2/O/sub 2/)/(Fe(II)) = 6 at pH 2.85 in 40 minutes. The overall results revealed that mineralization was rather slower as compared with the decolorization. (author)

  12. Aerobic SMBR/reverse osmosis system enhanced by Fenton oxidation for advanced treatment of old municipal landfill leachate.

    Science.gov (United States)

    Zhang, Guoliang; Qin, Lei; Meng, Qin; Fan, Zheng; Wu, Dexin

    2013-08-01

    A novel combined process of Fenton oxidation, submerged membrane bioreactor (SMBR) and reverse osmosis (RO) was applied as an appropriate option for old municipal landfill leachate treatment. Fenton process was designed to intensively solve the problem of non-biodegradable organic pollutant removal and low biodegradability of leachate, although the removal of ammonia-nitrogen was similar to 10%. After SMBR treatment, it not only presented a higher removal efficiency of organics, but also exhibited high ammonia-nitrogen removal of 80% on average. The variation of extracellular polymeric substance (EPS) content, zeta potential, and particle size of flocs after Fenton effluent continually fed in SMBR was found to be benefit for alleviating membrane fouling. Finally, three kinds of RO membranes (RE, CPA, and BW) were applied to treat SMBR effluents and successfully met wastewater re-utilization requirement. Compared with simple RO process, the troublesome membrane fouling can be effectively reduced in the combined process. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Treatment of real effluents from the pharmaceutical industry: A comparison between Fenton oxidation and conductive-diamond electro-oxidation.

    Science.gov (United States)

    Pérez, J F; Llanos, J; Sáez, C; López, C; Cañizares, P; Rodrigo, M A

    2017-06-15

    Wastewater produced in pharmaceutical manufacturing plants (PMPs), especially the one coming from organic-synthesis facilities, is characterized by its large variability due to the wide range of solvents and chemical reagents used in the different stages of the production of medicines. Normally, the toxicity of the organic compounds prevent the utilization of biological processes and more powerful treatments are needed becoming advanced oxidation processes (AOPs) a valid alternative. In this work, the efficiency in abatement of pollution by Fenton oxidation (FO) and conductive-diamond electro-oxidation (CDEO) are compared in the treatment of 60 real effluents coming from different processes carried out in a pharmaceutical facility, using standardized tests. In 80% of the samples, CDEO was found to be more efficient than FO and in the remaining 20%, coagulation was found to exhibit a great significance in the COD abatement mechanism during FO, pointing out the effectiveness of the oxidation promoted by the electrochemical technology. Mean oxidation state of carbon was found to be a relevant parameter to understand the behavior of the oxidation technologies. It varied inversely proportional to efficiency in FO and it showed practically no influence in the case of CDEO. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Iron Amendment and Fenton Oxidation of MTBE-Spent Granular Activated Carbon

    Science.gov (United States)

    Fenton-driven regeneration of Methyl tert-butyl ether (MTBE)-spent granular activated carbon (GAC) involves Fe amendment to the GAC to catalyze H2O2 reactions and to enhance the rate of MTBE oxidation and GAC regeneration. Four forms of iron (ferric sulfate, ferric chloride, fer...

  15. Photo oxidative degradation of azure-B by sono-photo-Fenton and photo-Fenton reagents

    Directory of Open Access Journals (Sweden)

    Prahlad Vaishnave

    2014-12-01

    Full Text Available A model for the decomposition of azure-B by photo-Fenton reagent in the presence of ultrasound in homogeneous aqueous solution has been described. The photochemical decomposition rate of azure-B is markedly increased in the presence of ultrasound. It is a rather inexpensive reagent for wastewater treatment. The effect of different variables like the concentration of ferric ion, concentration of dye, hydrogen peroxide, pH, light intensity etc. on the reaction rate has been observed. The progress of the sono-photochemical degradation was monitored spectrophotometrically. The optimum sono-photochemical degradation conditions were experimentally determined. The results showed that the dye was completely oxidized and degraded into CO2 and H2O. A suitable tentative mechanism for sono-photochemical bleaching of azure-B by sono-photo-Fenton’s reaction has been proposed.

  16. Case study of the application of Fenton process to highly polluted wastewater from power plant.

    Science.gov (United States)

    Pliego, Gema; Zazo, Juan A; Casas, Jose A; Rodriguez, Juan J

    2013-05-15

    This work investigates the application of Fenton process to the treatment of a highly polluted industrial wastewater resulting from the pipeline cleaning in a power plant. This effluent is characterized by a high chemical oxygen demand (COD>40 g/L), low biodegradability and quite a high iron concentration (around 3g/L) this coming from pipeline corrosion. The effect of the initial reaction temperature (between 50 and 90 °C) and the way of feeding H2O2 on the mineralization percentage and the efficiency of H2O2 consumption has been analyzed. With the stoichiometric amount of H2O2 relative to initial COD, fed in continuous mode, more than 90% COD reduction was achieved at 90 °C. That was accompanied by a dramatic improvement of the biodegradability. Thus, a combined treatment based on semicontinuous high-temperature Fenton oxidation (SHTF) and conventional aerobic biological treatment would allow fulfilling the COD and ecotoxicity regional limits for industrial wastewaters into de municipal sewer system. For the sake of comparison, catalytic wet air oxidation was also tested with poor results (less than 30% COD removal at 140 °C and 8 atm oxygen pressure). Copyright © 2013 Elsevier B.V. All rights reserved.

  17. An overview on the removal of synthetic dyes from water by electrochemical advanced oxidation processes.

    Science.gov (United States)

    Nidheesh, P V; Zhou, Minghua; Oturan, Mehmet A

    2018-04-01

    Wastewater containing dyes are one of the major threats to our environment. Conventional methods are insufficient for the removal of these persistent organic pollutants. Recently much attention has been received for the oxidative removal of various organic pollutants by electrochemically generated hydroxyl radical. This review article aims to provide the recent trends in the field of various Electrochemical Advanced Oxidation Processes (EAOPs) used for removing dyes from water medium. The characteristics, fundamentals and recent advances in each processes namely anodic oxidation, electro-Fenton, peroxicoagulation, fered Fenton, anodic Fenton, photoelectro-Fenton, sonoelectro-Fenton, bioelectro-Fenton etc. have been examined in detail. These processes have great potential to destroy persistent organic pollutants in aqueous medium and most of the studies reported complete removal of dyes from water. The great capacity of these processes indicates that EAOPs constitute a promising technology for the treatment of the dye contaminated effluents. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Complete removal of AHPS synthetic dye from water using new electro-fenton oxidation catalyzed by natural pyrite as heterogeneous catalyst.

    Science.gov (United States)

    Labiadh, Lazhar; Oturan, Mehmet A; Panizza, Marco; Hamadi, Nawfel Ben; Ammar, Salah

    2015-10-30

    The mineralization of a new azo dye - the (4-amino-3-hydroxy-2-p-tolylazo-naphthalene-1-sulfonic acid) (AHPS) - has been studied by a novel electrochemical advanced oxidation process (EAOP), consisting in electro-Fenton (EF) oxidation, catalyzed by pyrite as the heterogeneous catalyst - the so-called 'pyrite-EF'. This solid pyrite used as heterogeneous catalyst instead of a soluble iron salt, is the catalyst the system needs for production of hydroxyl radicals. Experiments were performed in an undivided cell equipped with a BDD anode and a commercial carbon felt cathode to electrogenerate in situ H2O2 and regenerate ferrous ions as catalyst. The effects on operating parameters, such as applied current, pyrite concentration and initial dye content, were investigated. AHPS decay and mineralization efficiencies were monitored by HPLC analyses and TOC measurements, respectively. Experimental results showed that AHPS was quickly oxidized by hydroxyl radicals (OH) produced simultaneously both on BDD surface by water discharge and in solution bulk from electrochemically assisted Fenton's reaction with a pseudo-first-order reaction. AHPS solutions with 175 mg L(-1) (100 mg L(-1) initial TOC) content were then almost completely mineralized in 8h. Moreover, the results demonstrated that, under the same conditions, AHPS degradation by pyrite electro-Fenton process was more powerful than the conventional electro-Fenton process. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Supported Nanosized α-FeOOH Improves Efficiency of Photoelectro-Fenton Process with Reaction-Controlled pH Adjustment for Sustainable Water Treatment

    Directory of Open Access Journals (Sweden)

    Chuan Wang

    2012-01-01

    Full Text Available The overall photoelectro-Fenton (PE-Fenton process for water treatment with neutral initial pH includes three steps of pH reduction, PE-Fenton reaction, and pH elevation. Reaction-controlled pH adjustment (RCpA, which utilizes the intrinsic electrochemical reactions instead of chemical addition, has been employed to lower the pH, maintain the lowered pH for the Fenton reaction, and recover the pH for final effluent discharge. This study demonstrated that the overall efficiency of this sustainable PE-Fenton process was improved by rapidly recycling the iron substance. Nanosized iron oxide was prepared and employed to ensure such rapid recycling. SEM and XRD results showed that the as-prepared iron oxide was α-FeOOH with 20 nm in size. The experimental results of dimethyl phthalate (DMP degradation showed that diatomite-supported α-FeOOH (N-α-FeOOH/diatomite could efficiently reduce the DMP concentration and total organic carbon. Furthermore, compared with Fe3+, the N-α-FeOOH/diatomite saved 160 min for iron settlement at 20 mg L−1 DMP concentration. Also, with the increment in the initial DMP concentration, extra energy consumed by the individual step of PE-Fenton reaction using the N-α-FeOOH/diatomite became negligible compared with that using free iron ions with the increment in the initial DMP concentration. This development is expected to be a major step of the PE-Fenton process with RCpA towards actual water treatment.

  20. Combined heterogeneous Electro-Fenton and biological process for the treatment of stabilized landfill leachate.

    Science.gov (United States)

    Baiju, Archa; Gandhimathi, R; Ramesh, S T; Nidheesh, P V

    2018-03-15

    Treatment of stabilized landfill leachate is a great challenge due to its poor biodegradability. Present study made an attempt to treat this wastewater by combining electro-Fenton (E-Fenton) and biological process. E-Fenton treatment was applied prior to biological process to enhance the biodegradability of leachate, which will be beneficial for the subsequent biological process. This study also investigates the efficiency of iron molybdophosphate (FeMoPO) nanoparticles as a heterogeneous catalyst in E-Fenton process. The effects of initial pH, catalyst dosage, applied voltage and electrode spacing on Chemical Oxygen Demand (COD) removal efficiency were analyzed to determine the optimum conditions. Heterogeneous E-Fenton process gave 82% COD removal at pH 2, catalyst dosage of 50 mg/L, voltage 5 V, electrode spacing 3 cm and electrode area 25 cm 2 . Combined E-Fenton and biological treatment resulted an overall COD removal of 97%, bringing down the final COD to 192 mg/L. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Removal of organic pollutants in tannery wastewater from wet-blue fur processing by integrated Anoxic/Oxic (A/O) and Fenton: Process optimization

    DEFF Research Database (Denmark)

    Wang, Yong; Li, Weiguang; Angelidaki, Irini

    2014-01-01

    Treatment of tannery wastewater has been a challenge in remediation of aquatic environment in developing countries. Removal of organic pollutants in tannery wastewater from wet-blue fur processing was studied using integrated processes of Anoxic/Oxic and Fenton. Analysis of COD composition based...... 80%. In the subsequent Fenton oxidation, effects of initial pH and H2O2 dose on COD removal were investigated, and response surface methodology was adopted to obtain the optimal conditions as initial pH of 4.0, H2O2 dose of 14.0mM, H2O2:Fe2+ molar ratio of 10.6, and reaction time of 3h to achieve...... the highest COD removal of 55.87%. GC-MS analysis was carried out to observe the change of organic composition during Fenton oxidation, and most of the residual organic pollutants resistant to Fenton treatment belonged to organosilanes and saturated alkanes. This study will provide useful information...

  2. Tratamento de águas contaminadas por diesel/biodiesel utilizando processo Fenton Treatment of water contaminated by diesel/biodiesel using Fenton process

    Directory of Open Access Journals (Sweden)

    Teofani Koslides Mitre

    2012-06-01

    Full Text Available A contaminação de águas por misturas diesel/biodiesel pode causar grandes impactos ambientais, relacionados à presença de compostos orgânicos recalcitrantes e tóxicos, inviabilizando o uso de processos biológicos de tratamento. A avaliação da biodegradabilidade, nas proporções B0, B25, B50, B75 e B100 (os números especificam o percentual em massa de biodiesel na mistura, indicou que a adição de biodiesel em teores acima de 50% aumenta a biodegradabilidade, alcançando 60 e 80% para B50 e B75, respectivamente. Na aplicação do processo Fenton, a remoção da matéria orgânica foi superior a 80% em todas as misturas, exceto para B0, que apresentou remoção máxima de 50%. A oxidação por Fenton se ajustou a um modelo cinético de pseudo-segunda ordem em relação à concentração de matéria orgânica, e resultou em aumento da biodegradabilidade de até 150%.Waters contaminated with diesel/biodiesel and their blends can cause major environmental impacts, due to the presence of toxic and recalcitrant organic compounds, which invalidate the use of biological treatment processes. Evaluation of biodegradability of the blends B0, B25, B50, B75 and B100 (the numbers specify the mass percentage of biodiesel in the blend indicated that the addition of biodiesel at concentrations above 50% increased biodegradation, reaching 60 and 80% for B50 and B75, respectively. When the Fenton process was used, removal of organic matter was greater than 80 % in all blends, except for B0, which showed maximum removal of 60%. Oxidation by Fenton was fitted with a pseudo-second order kinetic model in relation to the concentration of organic matter and resulted in increased biodegradation of up to 150%.

  3. p-Chlorophenol Oxidation in Industrial Effluent by Ultrasonic/Fenton Technology

    Directory of Open Access Journals (Sweden)

    Abdolmotaleb Seid Mohammadi

    2012-01-01

    Full Text Available Phenolic compounds have become a cause for of worldwide concern due to their persistence, toxicity and health risks. Hence, removal of these pollutants from aqueous effluents is an important practical problem. Ultrasonic technology may be used for water and wastewater treatment as an advanced oxidation process. Application of this technology, leads to the decomposition of many organic compounds during cavitation process. The degradation of 4-chlorophenol in aqueous solution under sonolysis at 45 kHz coupled with fFenton process was is investigated. The oxidation rate was influenced by many factors, such as the pH value, the amount of hydrogen peroxide, catalyst (FeSO4 and initial p-chlorophenol concentration. The experimental results showed that the decomposition of p-chlorophenol was affected by the various reaction conditions. The optimum conditions obtained for the best degradation rate were pH=3, H2O2 concentration of 0.05 mol/L and 0.025 mmol/L for catalyst, respectively. Also it was observed that the degradation of p-chlorophenol depended on its initial concentration

  4. Identification of intermediates, acute toxicity removal, and kinetics investigation to the Ametryn treatment by direct photolysis (UV254), UV254/H2O2, Fenton, and photo-Fenton processes.

    Science.gov (United States)

    de Oliveira, Dirce Martins; Cavalcante, Rodrigo Pereira; da Silva, Lucas de Melo; Sans, Carme; Esplugas, Santiago; de Oliveira, Silvio Cesar; Junior, Amilcar Machulek

    2018-02-09

    This paper reports the degradation of 10 mg L -1 Ametryn solution with different advanced oxidation processes and by ultraviolet (UV 254 ) irradiation alone with the main objective of reducing acute toxicity and increase biodegradability. The investigated factors included Fe 2+ and H 2 O 2 concentrations. The effectiveness of the UV 254 and UV 254 /H 2 O 2 processes were investigated using a low-pressure mercury UV lamp (254 nm). Photo-Fenton process was explored using a blacklight blue lamp (BLB, λ = 365 nm). The UV 254 irradiation process achieved complete degradation of Ametryn solution after 60 min. The degradation time of Ametryn was greatly improved by the addition of H 2 O 2 . It is worth pointing out that a high rate of Ametryn removal was attained even at low concentrations of H 2 O 2 . The kinetic constant of the reaction between Ametryn and HO ● for UV 254 /H 2 O 2 was 3.53 × 10 8  L mol -1  s -1 . The complete Ametryn degradation by the Fenton and photo-Fenton processes was observed following 10 min of reaction for various combinations of Fe 2+ and H 2 O 2 under investigation. Working with the highest concentration (150 mg L -1 H 2 O 2 and 10 mg L -1 Fe 2+ ), around 30 and 70% of TOC removal were reached within 120 min of treatment by Fenton and photo-Fenton processes, respectively. Although it did not obtain complete mineralization, the intermediates formed in the degradation processes were hydroxylated and did not promote acute toxicity of Vibrio fischeri. Furthermore, a substantial improvement of biodegradability was obtained for all studied processes.

  5. Enhancement of Fenton and photo-Fenton processes at initial circumneutral pH for the degradation of the β-blocker metoprolol.

    Science.gov (United States)

    Romero, V; Acevedo, S; Marco, P; Giménez, J; Esplugas, S

    2016-01-01

    The need for acidification in the Fenton and photo-Fenton process is often outlined as one of its major drawbacks, thus in this work the acidification of the Metoprolol (MET) is avoided by the addition of resorcinol (RES), which is used to simulate model organic matter. The experiments were carried out at natural pH (6.2) with different Fe(2+) (1, 2.5, 5, and 10 mg/L) and H2O2 (25, 50, 125 and 150 mg/L) concentrations. The performance of MET and RES degradation was assessed along the reaction time. Working with the highest concentrations (5 and 10 mg/L of ferrous iron and 125 and 150 mg/L of H2O2) more than 90% of MET and RES removals were reached within 50 and 20 min of treatment, respectively, by Fenton process. However a low mineralization was achieved in both cases, likely, due to by-products accumulation. Regarding to photo-Fenton process, within 3 min with the highest iron and hydrogen peroxide concentrations, a complete MET degradation was obtained and 95% of RES conversion was achieved. Parameters such Total Organic Carbon, Chemical Oxygen Demand, and AOS were measured. Intermediates were identified and MET degradation path was proposed in the presence of resorcinol. Finally, a comparison between Fenton and photo-Fenton processes at acid pH and at initial circumneutral pH was discussed. The positive effect of RES on Fenton and photo-Fenton systems has been confirmed, allowing the work at circumneutral pH. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. A Comparative Analysis of 2-(Thiocyanomethylthio-Benzothiazole Degradation Using Electro-Fenton and Anodic Oxidation on a Boron-Doped Diamond Electrode

    Directory of Open Access Journals (Sweden)

    Armando Vázquez

    2018-01-01

    Full Text Available 2-(Thiocyanomethylthio-benzothiazole (TCMTB is used as fungicide in the paper, tannery, paint, and coatings industries, and its study is important as it is considered toxic to aquatic life. In this study, a comparison of direct anodic oxidation (AO using a boron-doped diamond electrode (BDD and electro-Fenton (EF processes for TCMTB degradation in acidic chloride and sulfate media using a FM01-LC reactor was performed. The results of the electrolysis processes studied in the FM01-LC reactor showed a higher degradation of TCMTB with the anodic oxidation process than with the electro-Fenton process, reaching 81% degradation for the former process versus 47% degradation for the latter process. This difference was attributed to the decrease in H2O2 during the EF process, due to parallel oxidation of chlorides. The degradation rate and current efficiency increased as a function of volumetric flow rate, indicating that convection promotes anodic oxidation and electro-Fenton processes. The results showed that both AO and EF processes could be useful strategies for TCMTB toxicity reduction in wastewaters.

  7. The study of a pilot-scale aerobic/Fenton/anoxic/aerobic process system for the treatment of landfill leachate.

    Science.gov (United States)

    Hu, Wenyong; Zhou, Yu; Min, Xiaobo; Liu, Jingyi; Li, Xinyu; Luo, Lin; Zhang, Jiachao; Mao, Qiming; Chai, Liyuan; Zhou, YaoYu

    2017-06-29

    In this study, a combined aerobic-Fenton-anoxic/aerobic system was designed for the remediation of raw landfill leachate in a pilot-scale experiment. This system included (i) a granular sludge biological oxidation procedure that achieves the accumulation of nitrite nitrogen ([Formula: see text]) under aerobic conditions; (ii) a Fenton process that improves the biodegradability of the biotreated leachate and (iii) an activated sludge biological oxidation component under anoxic and aerobic conditions. Additionally, a shortcut nitrification and denitrification pathway was achieved. The effects of free ammonia, temperature and pH on nitrite accumulation were discussed. The change in the biochemical oxygen demand/chemical oxygen demand ratio of the effluent after shortcut nitrification was also analysed. The microbial community in the reactor were also investigated. The problem of the lack of carbon source in the denitrification process can be solved by the Fenton reagent method. Moreover, it was beneficial to achieving nitrogen removal as well as the more extensive removal of organic matter. The treatment strategy employed in this study exhibited good results and provided the potential practical application for treating landfill leachate.

  8. Optimization of Fenton's oxidation of herbicide dicamba in water using response surface methodology

    Science.gov (United States)

    Sangami, Sanjeev; Manu, Basavaraju

    2017-12-01

    In this study Fenton's oxidation of dicamba in aqueous medium was investigated by using the response surface methodology. The influence of H2O2/COD ( A), H2O2/Fe2+ ( B), pH ( C) and reaction time ( D) as independent variables were studied on two responses (COD and dicamba removal efficiency). The dosage of H2O2 (5.35-17.4 mM) and Fe2+ (0.09-2.13 mM) were varied and optimum percentage removal of dicamba of 84.01% with H2O2 and Fe2+ dosage of 11.38 and 0.33 mM respectively. The whole oxidation process was monitored by high performance liquid chromatography (HPLC) along with liquid chromatography/mass spectrometry (LC/MS). It was found that 82% of dicamba was mineralized to oxalic acid, chloride ion, CO2 and H2O, which was confirmed with COD removal of 81.53%. The regression analysis was performed, in which standard deviation (2.74), coefficient of correlation ( R 2 = R_{adj}2) and adequate precision (>12) were in good agreement with model values. Finally, the treatment process was validated by performing the additional experiments.

  9. Research on the Treatment of Aluminum Alloy Chemical Milling Wastewater with Fenton Process

    Science.gov (United States)

    Zong-liang, Huang; Ru, Li; Peng, Luo; Jun-li, Gu

    2018-03-01

    The aluminum alloy chemical milling wastewater was treated by Fenton method. The effect of pH value, reaction time, rotational speed, H2O2 dosage, Fe2+ dosage and the molar ratio between H2O2 and Fe2+ on the COD removal rate of aluminum alloy chemical milling wastewater were investigated by single factor experiment and orthogonal experiment. The results showed that the optimum operating conditions for Fenton oxidation were as follows: the initial pH value was 3, the rotational speed was 250r/min, the molar ratio of H2O2 and Fe2+ was 8, the reaction time was 90 min. Under the optimum conditions, the removal rate of the wastewater’s COD is about 72.36%. In the reaction kinetics that aluminum alloy chemical milling wastewater was oxidized and degraded by Fenton method under the optimum conditions, the reaction sequence of the initial COD was 0.8204.

  10. Fenton Coagulation/Oxidation Using Fe2+ and Fe3+ Íons and Peracetic Acid for the Treatment of Wastewater

    Directory of Open Access Journals (Sweden)

    Grasiele Soares Cavallini

    2015-09-01

    Full Text Available The Fenton coagulation/oxidation process is divided into two steps: coagulation, in alkaline pH and oxidation, in acid pH. This configuration provides a reduction in oxidant concentration, due to the pretreatment conducted in the coagulation step. This study proposes the substitution of hydrogen peroxide (HP by peracetic acid (PAA in a Fenton coagulation process to treat sanitary sewage and provide its disinfection. The new combination is proposed in a single step and presented good results in removing turbidity (98.5%, apparent color (95.4%, phosphorus (100% and COD (58.2% even at the effluent natural pH, besides demonstrating higher reduction in E. coli when compared with the process that employs hydrogen peroxide. The formation of Fe3+ ions was shown to be responsible for the removal of the particulate material. DOI: http://dx.doi.org/10.17807/orbital.v7i3.626 

  11. IRON OPTIMIZATION FOR FENTON-DRIVEN OXIDATION OF MTBE-SPENT GRANULAR ACTIVATED CARBON

    Science.gov (United States)

    Fenton-driven chemical regeneration of granular activated carbon (GAC) is accomplished through the addition of H2O2 and iron (Fe) to spent GAC. The overall objective of this treatment process is to transform target contaminants into less toxic byproducts, re-establish the sorpti...

  12. Optimization of photo-Fenton process for the treatment of prednisolone.

    Science.gov (United States)

    Díez, Aida María; Ribeiro, Ana Sofia; Sanromán, Maria Angeles; Pazos, Marta

    2018-03-29

    Prednisolone is a widely prescribed synthetic glucocorticoid and stated to be toxic to a number of non-target aquatic organisms. Its extensive consumption generates environmental concern due to its detection in wastewater samples at concentrations ranged from ng/L to μg/L that requests the application of suitable degradation processes. Regarding the actual treatment options, advanced oxidation processes (AOPs) are presented as a viable alternative. In this work, the comparison in terms of pollutant removal and energetic efficiencies, between different AOPs such as Fenton (F), photo-Fenton (UV/F), photolysis (UV), and hydrogen peroxide/photolysis (UV/H 2 O 2 ), was carried out. Light diode emission (LED) was the selected source to provide the UV radiation. The UV/F process revealed the best performance, reaching high levels of both degradation and mineralization with low energy consumption. Its optimization was conducted and the operational parameters were iron and H 2 O 2 concentrations and the working volume. Using the response surface methodology with the Box-Behnken design, the effect of independent variables and their interactions on the process response were effectively evaluated. Different responses were analyzed taking into account the prednisolone removal (TOC and drug abatements) and the energy consumptions associated. The obtained model showed an improvement of the UV/F process when treating smaller volumes and when adding high concentrations of H 2 O 2 and Fe 2+ . The validation of this model was successfully carried out, having only 5% of discrepancy between the model and the experimental results. Finally, the performance of the process when having a real wastewater matrix was also tested, achieving complete mineralization and detoxification after 8 h. In addition, prednisolone degradation products were identified. Finally, the obtained low energy permitted to confirm the viability of the process.

  13. Comparative use of anodic oxidation, electro-Fenton and photoelectro-Fenton with Pt or boron-doped diamond anode to decolorize and mineralize Malachite Green oxalate dye

    International Nuclear Information System (INIS)

    El-Ghenymy, Abdellatif; Centellas, Francesc; Rodríguez, Rosa María; Cabot, Pere Lluís; Garrido, José Antonio; Sirés, Ignasi; Brillas, Enric

    2015-01-01

    Highlights: • Degradation of Malachite Green oxalate solutions at pH 3.0 by AO, AO-H 2 O 2 , EF and PEF. • A Pt anode leads to slower decolorization and mineralization than BDD. • Up to 97% mineralization by the most powerful PEF process with BDD at 100 mA cm −2 . • Study of the evolution of seven final short-chain aliphatic carboxylic acids. • Conversion of the initial N atoms of the dye mainly into NH 4 + , along with small amounts of NO 3 − . - Abstract: The degradation of 100 cm 3 of 177 mg dm −3 of the triphenylmethane dye Malachite Green oxalate at pH 3.0 was studied by anodic oxidation with stainless steel cathode (AO-SS), AO with air-diffusion cathode (AO-H 2 O 2 ), electro-Fenton (EF) and photoelectro-Fenton (PEF) with UVA light. The main oxidizing species were hydroxyl radicals formed from either water oxidation at the anode surface or in the bulk between added Fe 2+ and H 2 O 2 generated at the air-diffusion cathode. The use of a Pt anode led to slower decolorization and mineralization than BDD in all treatments because of the higher oxidation power of the latter. The decolorization was much faster for EF and PEF compared to AO-SS and AO-H 2 O 2 due to the contribution of hydroxyl radicals in the bulk. PEF allowed the quickest color removal by the rapid Fe 2+ regeneration from the photolysis of Fe(III) complexes with oxalate. The most powerful process was PEF with BDD, which yielded total decolorization in 6 min and 97% mineralization at 240 min operating at 100 mA cm −2 , thanks to hydroxyl radicals formed at the anode surface and in the bulk along with the photolytic action of UVA radiation. The evolution of final carboxylic acids like maleic, fumaric, succinic, acetic, oxalic, formic and oxamic was followed by ion-exclusion HPLC. All these acids and their Fe(III) complexes were removed more slowly with Pt anode. The initial N atoms of the dye were pre-eminently accumulated as NH 4 + ion, along with small amounts of NO 3 − ion.

  14. Anodic oxidation, electro-Fenton and photoelectro-Fenton degradations of pyridinium- and imidazolium-based ionic liquids in waters using a BDD/air-diffusion cell

    International Nuclear Information System (INIS)

    Garcia-Segura, Sergi; Lima, Álvaro Silva; Cavalcanti, Eliane Bezerra; Brillas, Enric

    2016-01-01

    Highlights: • Treatment of 1-butyl-4-methylpyridinium chloride and 1-ethyl-3-methylimidazolium chloride. • Almost total mineralization of both compounds by AO-H_2O_2, EF and PEF at high current density. • Release of NH_4"+ and NO_3"− in different proportion depending on the ionic liquid. • Large decay of initial Cl"− with main formation of ClO_3"− and, in lesser extent, of ClO_4"−. • Detection of primary heteroaromatic products and carboxylic acids generated. - Abstract: The degradation of two representative ionic liquids, 1-butyl-4-methylpyridinium chloride and 1-ethyl-3-methylimidazolium chloride, has been studied in 100 cm"3 of aqueous sulfate medium of pH 3.0 by electrochemical advanced oxidation processes (EAOPs) like anodic oxidation with electrogenerated H_2O_2 (AO-H_2O_2), electro-Fenton (EF) and photoelectro-Fenton (PEF). The electrolytic cell contained a boron-doped diamond (BDD) anode and an air diffusion cathode. The main oxidants were hydroxyl radicals formed at the anode surface from water discharge and in the bulk from Fenton’s reaction between generated H_2O_2 and added Fe"2"+. The solutions of both compounds underwent an almost total mineralization with 97% and 94% of dissolved organic abatement by the most powerful PEF at high current density, being similar and slightly lower for AO-H_2O_2 and EF, respectively. At low current density, the pyridinium-based ionic liquid showed similar mineralization rate by AO-H_2O_2 and PEF, whereas the imidazolium-based ionic liquid was more rapidly degraded in the sequence: AO-H_2O_2 < EF < PEF, where the positive effect of UVA irradiation in PEF was more apparent. The current efficiency decreased gradually with increasing current density in all EAOPs and its value was always superior for the latter compound. The NO_3"− and NH_4"+ concentrations produced in each process were quantified by ion chromatography. This technique confirmed a drastic oxidation of Cl"− contained in the parent

  15. Novel RGO/α-FeOOH supported catalyst for Fenton oxidation of phenol at a wide pH range using solar-light-driven irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ying, E-mail: yingwang@bnu.edu.cn [The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875 (China); Fang, Jiasheng, E-mail: fangfangcanfly@163.com [The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875 (China); School of Chemistry and Chemical Engineering, Southeast University, Jiangsu Optoelectronic Functional Materials and Engineering Laboratory, Nanjing 211189 (China); Crittenden, John C., E-mail: John.Crittenden@ce.gatech.edu [School of Civil and Environmental Engineering and the Brook Byers Institute for Sustainable Systems, Georgia Institute of Technology, Atlanta, GA 30332-0595 (United States); Shen, Chanchan [The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing 100875 (China)

    2017-05-05

    Graphical abstract: Schematic of the preparation of RF supported catalysts and the reaction mechanism for SLD Fenton catalytic degradation of aqueous phenol. - Highlights: • Novel SLD Fenton catalyst was synthesized via in-situ induced self-assembly process. • RGO improved light-harvesting capacity and enhanced electro-transport performance. • Visible light irradiation accelerated reaction and extended operating pHs (4.0–8.0). • H{sub 2}O{sub 2} reduction and H{sub 2}O oxidation yielded ·OH in Fe{sup Ⅱ}/Fe{sup Ⅲ} and Fe{sup Ⅲ}/Fe{sup Ⅳ} cycling process. - Abstract: A novel solar-light-driven (SLD) Fenton catalyst was developed by reducing the ferrous-ion onto graphene oxide (GO) and forming reduced graphene oxide/α-FeOOH composites (RF) via in-situ induced self-assembly process. The RF was supported on several mesoporous supports (i.e., Al-MCM-41, MCM-41 and γ-Al{sub 2}O{sub 3}). The activity, stability and energy use for phenol oxidation were systematically studied for a wide pH range. Furthermore, the catalytic mechanism at acid and alkaline aqueous conditions was also elucidated. The results showed that Fe(II) was reduced onto GO nanosheets and α-FeOOH crystals were formed during the self-assembly process. Compared with Fenton reaction without SLD irradiation, the visible light irradiation not only dramatically accelerated the rate of Fenton-based reactions, but also extended the operating pH for the Fenton reaction (from 4.0 to 8.0). The phenol oxidation on RF supported catalysts was fitting well with the pseudo-first-order kinetics, and needed low initiating energy, insensitive to the reacting temperature changes (273–318 K). The Al-MCM-41 supported RF was a more highly energy-efficient catalyst with the prominent catalytic activity at wide operating pHs. During the reaction, ·OH radicals were generated by the SLD irradiation from H{sub 2}O{sub 2} reduction and H{sub 2}O oxidation in the Fe{sup Ⅱ}/Fe{sup Ⅲ} and Fe{sup Ⅲ}/Fe{sup

  16. Reduction of COD in wastewater from an organized tannery industrial region by Electro-Fenton process

    International Nuclear Information System (INIS)

    Kurt, Ugur; Apaydin, Omer; Gonullu, M. Talha

    2007-01-01

    Advanced oxidation processes (AOPs) have led the way in the treatment of aqueous waste and are rapidly becoming the chosen technology for many applications. In this paper, COD reduction potential of leather tanning industry wastewaters by Electro-Fenton (EF) oxidation, as one of the AOPs, was experimentally evaluated. The wastewater sample was taken from an outlet of an equalization basin in a common treatment plant of an organized tannery industrial region in Istanbul, Turkey. Treatment of the wastewater was carried out by an electrochemical batch reactor equipped with two iron electrodes, which were connected parallel to each other. The oxidation process was studied for optimization of H 2 O 2 and the electricity consumptions were observed at different contact times under different pH conditions (3.0, 5.0 and 7.2). In each case, electricity consumption for decreased COD mass was estimated. In this process, COD was reduced by 60-70% within 10 min. By taking into consideration the local sewerage discharge limit, applicability of EF process for the tannery wastewaters was evaluated

  17. Reduction of COD in wastewater from an organized tannery industrial region by Electro-Fenton process

    Energy Technology Data Exchange (ETDEWEB)

    Kurt, Ugur [Yildiz Technical University, Environmental Engineering Department, 34349 Istanbul (Turkey)]. E-mail: ukurt@yildiz.edu.tr; Apaydin, Omer [Yildiz Technical University, Environmental Engineering Department, 34349 Istanbul (Turkey)]. E-mail: apaydin@yildiz.edu.tr; Gonullu, M. Talha [Yildiz Technical University, Environmental Engineering Department, 34349 Istanbul (Turkey)]. E-mail: gonul@yildiz.edu.tr

    2007-05-08

    Advanced oxidation processes (AOPs) have led the way in the treatment of aqueous waste and are rapidly becoming the chosen technology for many applications. In this paper, COD reduction potential of leather tanning industry wastewaters by Electro-Fenton (EF) oxidation, as one of the AOPs, was experimentally evaluated. The wastewater sample was taken from an outlet of an equalization basin in a common treatment plant of an organized tannery industrial region in Istanbul, Turkey. Treatment of the wastewater was carried out by an electrochemical batch reactor equipped with two iron electrodes, which were connected parallel to each other. The oxidation process was studied for optimization of H{sub 2}O{sub 2} and the electricity consumptions were observed at different contact times under different pH conditions (3.0, 5.0 and 7.2). In each case, electricity consumption for decreased COD mass was estimated. In this process, COD was reduced by 60-70% within 10 min. By taking into consideration the local sewerage discharge limit, applicability of EF process for the tannery wastewaters was evaluated.

  18. Pyrrolic-N-doped graphene oxide/Fe2O3 mesocrystal nanocomposite: Efficient charge transfer and enhanced photo-Fenton catalytic activity

    Science.gov (United States)

    Liu, Bing; Tian, Lihong; Wang, Ran; Yang, Jinfeng; Guan, Rong; Chen, Xiaobo

    2017-11-01

    Though α-Fe2O3 has attracted much attention in photocatalytic or Fenton-catalytic degradation of organic contaminants, its performance is still unsatisfactory due to fast recombination of electrons and holes in photocatalytic process and the difficult conversion of Fe(II) and Fe(III) in Fenton reaction. Herein, a pyrrolic N-doped graphene oxide/Fe2O3 mesocrystal (NG-Fe2O3) nanocomposite with good distribution is synthesized by a simple solvothermal method and adjusting the oxygen-containing groups on graphene oxide. The morphology of NG-Fe2O3 contributes to a relatively large BET surface area and an intimate contact between NG and Fe2O3. These two important factors along with the excellent electro-conductivity of pyrrolic-N doped GO result in the efficient separation of electron-hole pairs and fast conversion of Fe(II)and Fe(III) in photo-Fenton synergistic reaction. Thus, a remarkably improved photo-Fenton catalytic activity of NG-Fe2O3 is obtained. The degrading rate on methyl blue increases by 1.5 times and the conversion rate of glyphosate increases by 2.3 times under visible light irradiation, compared to pristine α-Fe2O3 mesocrystals.

  19. Synthetic olive mill wastewater treatment by Fenton's process in batch and continuous reactors operation.

    Science.gov (United States)

    Esteves, Bruno M; Rodrigues, Carmen S D; Madeira, Luís M

    2017-11-04

    Degradation of total phenol (TPh) and organic matter, (expressed as total organic carbon TOC), of a simulated olive mill wastewater was evaluated by the Fenton oxidation process under batch and continuous mode conditions. A mixture of six phenolic acids usually found in these agro-industrial wastewaters was used for this purpose. The study focused on the optimization of key operational parameters of the Fenton process in a batch reactor, namely Fe 2+ dosage, hydrogen peroxide concentration, pH, and reaction temperature. On the assessment of the process efficiency, > 99% of TPh and > 56% of TOC removal were attained when [Fe 2+ ] = 100 ppm, [H 2 O 2 ] = 2.0 g/L, T = 30 °C, and initial pH = 5.0, after 300 min of reaction. Under those operational conditions, experiments on a continuous stirred-tank reactor (CSTR) were performed for different space-time values (τ). TOC and TPh removals of 47.5 and 96.9%, respectively, were reached at steady-state (for τ = 120 min). High removal of COD (> 75%) and BOD 5 (> 70%) was achieved for both batch and CSTR optimum conditions; analysis of the BOD 5 /COD ratio also revealed an increase in the effluent's biodegradability. Despite the high removal of lumped parameters, the treated effluent did not met the Portuguese legal limits for direct discharge of wastewaters into water bodies, which indicates that coupled chemical-biological process may be the best solution for real olive mill wastewater treatment.

  20. An oxidative desulfurization method using ultrasound/Fenton's reagent for obtaining low and/or ultra-low sulfur diesel fuel

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Yongchuan; Qi, Yutai [Department of Applied Chemistry, School of Science, Harbin Institute of Technology, Harbin 115001 (China); Zhao, Dezhi [Department of Petroleum Chemical Engineering, Liaoning Shihua University, Fushun 113001 (China); Zhang, Huicheng [Fushun Research Institute of Petroleum and Petrochemicals of SINOPEC Corp., Fushun 113001 (China)

    2008-10-15

    The total development trend in the world is towards continuously lower of sulfur content as a quality standard of diesel fuels. Integrating of an oxidative desulfurization unit with a conventional hydrotreating unit can bring benefits to producing low and/or ultra-low sulfur diesel fuels. Using the hydrotreated Middle East diesel fuel as a feedstock, four processes of the oxidative desulfurization have been studied: a hydrogen peroxide-acetic acid system and a Fenton's reagent system both without/with ultrasound. Results showed that the oxidative desulfurization reaction mechanics fitted apparent first-order kinetics. The addition of Fenton's reagent could enhance the oxidative desulfurization efficiency for diesel fuels and sono-oxidation treatment in combination with Fenton's reagent shows a good synergistic effect. Under our best operating condition for the oxidative desulfurization: temperature 313 K, ultrasonic power 200 W, ultrasonic frequency 28 kHz, Fe{sup 2+}/H{sub 2}O{sub 2} 0.05 mol/mol, pH 2.10 in aqueous phase and reaction time 15 min, the sulfur content in the diesel fuels was decreased from 568.75 {mu}g/g to 9.50 {mu}g/g. (author)

  1. Magnetic Fe2MO4 (M:Fe, Mn) activated carbons: Fabrication, characterization and heterogeneous Fenton oxidation of methyl orange

    International Nuclear Information System (INIS)

    Nguyen, Thi Dung; Phan, Ngoc Hoa; Do, Manh Huy; Ngo, Kim Tham

    2011-01-01

    We present a simple and efficient method for the fabrication of magnetic Fe 2 MO 4 (M:Fe and Mn) activated carbons (Fe 2 MO 4 /AC-H, M:Fe and Mn) by impregnating the activated carbon with simultaneous magnetic precursor and carbon modifying agent followed by calcination. The obtained samples were characterized by nitrogen adsorption isotherms, X-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM), and the catalytic activity in heterogeneous Fenton oxidation of methyl orange (MO) was evaluated. The resulting Fe 2 MnO 4 /AC-H showed higher catalytic activity in the methyl orange oxidation than Fe 3 O 4 /AC-H. The effect of operational parameters (pH, catalyst loading H 2 O 2 dosage and initial MO concentration) on degradation performance of the oxidation process was investigated. Stability and reusability of selected catalyst were also tested.

  2. Photo-catalytic degradation of an oil-water emulsion using the photo-fenton treatment process: effects and statistical optimization.

    Science.gov (United States)

    Tony, Maha A; Purcell, P J; Zhao, Y Q; Tayeb, A M; El-Sherbiny, M F

    2009-02-01

    The application of advanced oxidation processes (AOPs) to the treatment of an effluent contaminated with hydrocarbon oils was investigated. The AOPs conducted were Fe2+/H2O2 (Fenton's reagent), Fe2+/H2O2/UV (Photo-Fenton's reagent) and UV-photolysis. These technologies utilize the very strong oxidizing power of hydroxyl radicals to oxidize organic compounds to harmless end products such as CO2 and H2O. A synthetic wastewater generated by emulsifying diesel oil and water was used. This wastewater might simulate, for example, a waste resulting from a hydrocarbon oil spill, onto which detergent was sprayed. The experiments utilising the Photo-Fenton treatment method with an artificial UV source, coupled with Fenton's reagent, suggest that the hydrocarbon oil is readily degradable, but that the emulsifying agent is much more resistant to degradation. The results showed that the COD (chemical oxygen demand) removal rate was affected by the Photo-Fenton parameters (Fe2+, H2O2 concentrations and the initial pH) of the aqueous solution. In addition, the applicability of the treatment method to a 'real' wastewater contaminated with hydrocarbon oil is demonstrated. The 'real' wastewater was sourced at a nearby car-wash facility located at a petroleum filling station and the experimental results demonstrate the effectiveness of the treatment method in this case. A statistical analysis of the experimental data using the Statistical Analysis System (SAS) and the response surface methodology (RSM) based on the experimental design was applied to optimize the Photo-Fenton parameters (concentrations of Fe2+, H2O2 and initial pH) and to maximize the COD removal rate (more than 70%).

  3. Citric acid-modified Fenton's reaction for the oxidation of chlorinated ethylenes in soil solution systems.

    Science.gov (United States)

    Seol, Yongkoo; Javandel, Iraj

    2008-06-01

    Fenton's reagent, a solution of hydrogen peroxide and ferrous iron catalyst, is used for an in situ chemical oxidation of organic contaminants. Sulfuric acid is commonly used to create an acidic condition needed for catalytic oxidation. Fenton's reaction often involves pressure buildup and precipitation of reaction products, which can cause safety hazards and diminish efficiency. We selected citric acid, a food-grade substance, as an acidifying agent to evaluate its efficiencies for organic contaminant removal in Fenton's reaction, and examined the impacts of using citric acid on the unwanted reaction products. A series of batch and column experiments were performed with varying H2O2 concentrations to decompose selected chlorinated ethylenes. Either dissolved iron from soil or iron sulfate salt was added to provide the iron catalyst in the batch tests. Batch experiments revealed that both citric and sulfuric acid systems achieved over 90% contaminant removal rates, and the presence of iron catalyst was essential for effective decontamination. Batch tests with citric acid showed no signs of pressure accumulation and solid precipitations, however the results suggested that an excessive usage of H2O2 relative to iron catalysts (Fe2+/H2O2<1/330) would result in lowering the efficiency of contaminant removal by iron chelation in the citric acid system. Column tests confirmed that citric acid could provide suitable acidic conditions to achieve higher than 55% contaminant removal rates.

  4. Elimination of pyraclostrobin by simultaneous microbial degradation coupled with the Fenton process in microbial fuel cells and the microbial community.

    Science.gov (United States)

    Zhao, Huanhuan; Kong, Chui-Hua

    2018-06-01

    The elimination of pyraclostrobin by simultaneous microbial degradation and Fenton oxidation was achieved in a microbial fuel cell (MFC) system. After 12 h of incubation, the removal rate of pyraclostrobin was 1.4 mg/L/h at the anode and 1.7 mg/L/h at the cathode. The pyraclostrobin concentration was less than the detection limit (0.1 mg/L) after 72 h at the anode and 24 h at the cathode. The air flow rate, temperature, and pH of the catholyte had significant effects on the generation of H 2 O 2 . The maximum production of H 2 O 2 was 1.2 mg/L after reaction for 20 h during the Fenton process. Microbial community analysis indicated that functional bacteria in the genera Chryseobacterium, Stenotrophomonas, Arcobacter, and Comamonas were predominant in the anodic biofilm. In conclusion, the MFC-Fenton system provides an effective approach for treating environmental contaminants. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Treatment of petroleum refinery sourwater by advanced oxidation processes

    International Nuclear Information System (INIS)

    Coelho, Alessandra; Castro, Antonio V.; Dezotti, Marcia; Sant'Anna, G.L.

    2006-01-01

    The performance of several oxidation processes to remove organic pollutants from sourwater was investigated. Sourwater is a specific stream of petroleum refineries, which contains slowly biodegradable compounds and toxic substances that impair the industrial biological wastewater treatment system. Preliminary experiments were conducted, using the following processes: H 2 O 2 , H 2 O 2 /UV, UV, photocatalysis, ozonation, Fenton and photo-Fenton. All processes, except Fenton and photo-Fenton, did not lead to satisfactory results, reducing at most 35% of the sourwater dissolved organic carbon (DOC). Thus, further experiments were performed with these two techniques to evaluate process conditions and organic matter removal kinetics. Batch experiments revealed that the Fenton reaction is very fast and reaches, in a few minutes, an ultimate DOC removal of 13-27%, due to the formation of iron complexes. Radiation for an additional period of 60 min can increase DOC removal up to 87%. Experiments were also conducted in a continuous mode, operating one 0.4 L Fenton stirred reactor and one 1.6 L photo-Fenton reactor in series. DOC removals above 75% were reached, when the reaction system was operated with hydraulic retention times (HRT) higher than 85 min. An empirical mathematical model was proposed to represent the DOC removal kinetics, allowing predicting process performance quite satisfactorily

  6. Winery wastewater treatment by heterogeneous Photo-Fenton process and activated sludges; Depuracion de efluentes vinicolas ediante tratamientos Foto-Fenton en fase heterogenea y lodos activos

    Energy Technology Data Exchange (ETDEWEB)

    Mosteo, R.; Lalinde, N.; Ormad, Maria O. M.; Ovelleiro, J. L.

    2007-07-01

    The system composed by heterogeneous Photon-Fenton assisted by solar light and biological treatment based on activated sludge process treats adequately real winery wastewaters. the previous stage based on heterogeneous Photo-Fenton process produces a partial degradation of winery wastewaters and achieves a yield of degradation of organic matter (measured as TOC) close to 50%. The activated sludge process in simple stage doesn't present any operation problems (bulking phenomenon) and achieves a yield of degradation of organic matter of 90%. (Author) 16 refs.

  7. Simultaneous decomplexation in blended Cu(II)/Ni(II)-EDTA systems by electro-Fenton process using iron sacrificing electrodes.

    Science.gov (United States)

    Zhao, Zilong; Dong, Wenyi; Wang, Hongjie; Chen, Guanhan; Tang, Junyi; Wu, Yang

    2018-05-15

    This research explored the application of electro-Fenton (E-Fenton) technique for the simultaneous decomplexation in blended Cu(II)/Ni(II)-EDTA systems by using iron sacrificing electrodes. Standard discharge (0.3 mg L -1 for Cu and 0.1 mg L -1 for Ni in China) could be achieved after 30 min reaction under the optimum conditions (i.e. initial solution pH of 2.0, H 2 O 2 dosage of 6 mL L -1  h -1 , current density of 20 mA/cm 2 , inter-electrode distance of 2 cm, and sulfate electrolyte concentration of 2000 mg L -1 ). The distinct differences in apparent kinetic rate constants (k app ) and intermediate removal efficiencies corresponding to mere and blended systems indicated the mutual promotion effect toward the decomplexation between Cu(II) and Ni(II). Massive accumulation of Fe(Ⅲ) favored the further removal of Cu(II) and Ni(II) by metal ion substitution. Species distribution results demonstrated that the decomplexation of metal-EDTA in E-Fenton process was mainly contributed to the combination of various reactions, including Fenton reaction together with the anodic oxidation, electro-coagulation (E-coagulation) and electrodeposition. Unlike hypophosphite and citrate, the presence of chlorine ion displayed favorable effects on the removal efficiencies of Cu(II) and Ni(II) at low dosage, but facilitated the ammonia nitrogen (NH 4 + -N) removal only at high dosage. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Removal of Refractory Organics from Biologically Treated Landfill Leachate by Microwave Discharge Electrodeless Lamp Assisted Fenton Process

    Directory of Open Access Journals (Sweden)

    Jiuyi Li

    2015-01-01

    Full Text Available Biologically treated leachate usually contains considerable amount of refractory organics and trace concentrations of xenobiotic pollutants. Removal of refractory organics from biologically treated landfill leachate by a novel microwave discharge electrodeless lamp (MDEL assisted Fenton process was investigated in the present study in comparison to conventional Fenton and ultraviolet Fenton processes. Conventional Fenton and ultraviolet Fenton processes could substantially remove up to 70% of the refractory organics in a membrane bioreactor treated leachate. MDEL assisted Fenton process achieved excellent removal performance of the refractory components, and the effluent chemical oxygen demand concentration was lower than 100 mg L−1. Most organic matters were transformed into smaller compounds with molecular weights less than 1000 Da. Ten different polycyclic aromatic hydrocarbons were detected in the biologically treated leachate, most of which were effectively removed by MDEL-Fenton treatment. MDEL-Fenton process provides powerful capability in degradation of refractory and xenobiotic organic pollutants in landfill leachate and could be adopted as a single-stage polishing process for biologically treated landfill leachate to meet the stringent discharge limit.

  9. Fate of citalopram during water treatment with O3, ClO2, UV and fenton oxidation

    DEFF Research Database (Denmark)

    Hörsing, Maritha; Kosjek, Tina; Andersen, Henrik Rasmus

    2012-01-01

    In the present study we investigate the fate of citalopram (CIT) at neutral pH using advanced water treatment technologies that include O3, ClO2 oxidation, UV irradiation and Fenton oxidation. The ozonation resulted in 80% reduction after 30 min treatment. Oxidation with ClO2 removed >90% CIT...... at a dosage of 0.1 mg L−1. During UV irradiation 85% reduction was achieved after 5 min, while Fenton with addition of 14 mg L−1 (Fe2+) resulted in 90% reduction of CIT. During these treatment experiments transformation products (TPs) were formed from CIT, where five compounds were identified by using high...

  10. Efficient and Stable Carbon-coated Nickel Foam Cathodes for the Electro-Fenton Process

    International Nuclear Information System (INIS)

    Song, Shuqin; Wu, Mingmei; Liu, Yuhui; Zhu, Qiping; Tsiakaras, Panagiotis; Wang, Yi

    2015-01-01

    Highlights: • Carbon-coated nickel foam (C@NF) was prepared by cycle coating carbon process. • Ni leaching can be effectively controlled at C@NF4 (4 cycle coating times) cathode. • C@NF4 exhibits excellent electro-Fenton performance with desirable stability. • C@NF4 exhibits low energy consumption for DMP degradation. - Abstract: Carbon-coated nickel foam (C@NF) electrodes are prepared via a simple and effective method, hydrothermal-carbonization cycle coating process, characterized by scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS) and employed as the electro-Fenton (E-Fenton) cathode for degrading dimethyl phthalate (DMP) in aqueous solution. For the sake of comparison, nickel foam (NF) electrode and the conventional E-Fenton cathode (graphite gas diffusion electrode (GDE)) are also tested and compared. Experimental results indicate that nickel leaching can be effectively controlled at C@NF4 cathode (4 times cycle coating process), having great significance for promoting the application of NF in E-Fenton system. Moreover, C@NF4 cathode still presents excellent and effective performance on DMP degradation. DMP can be completely degraded within 2 h at −0.5 V and the total organic carbon (TOC) removal reaches as high as 82.1 %, which is almost 3 times as high as that at graphite GDE. Futhermore, the current efficiency for H 2 O 2 generation at C@NF4 is enhanced by 12 times compared to that at NF, and consequently the energy consumption during DMP degradation at C@NF4 is obvious lower than that at both NF cathode and graphite GDE. From the obtained results it can be deduced that C@NF4 is promising to be an attractive alternative E-Fenton cathode for removing organic pollutants in wastewater

  11. Fenton-like initiation of a toluene transformation mechanism

    Science.gov (United States)

    In Fenton-driven oxidation treatment systems, reaction intermediates derived from parent compounds can play a significant role in the overall treatment process. Fenton-like reactions in the presence of toluene or benzene, involved a transformation mechanism that was highly effici...

  12. Applying fenton process in acrylic fiber wastewater treatment and practice teaching

    Science.gov (United States)

    Zhang, Chunhui; Jiang, Shan

    2018-02-01

    Acrylic fiber manufacturing wastewater, containing a wider range of pollutants, high concentration of refractory organics, poisonous and harmful matters, was significant to treat from the effluents of wastewater treatment plants (WWTPs). In this work, a Fenton reactor was employed for advanced treatment of the WWTP effluents. An orthogonal test and a parametric study were carried out to determine the effect of the main operating conditions and the Fenton process attain excellent performance on the degradation of pollutants under an optimal condition of ferrous dosage was 6.25 mM, hydrogen peroxide was 75 mM and initial pH value was 3.0 in 90 min reaction time. The removal efficiency of COD, TOC, NH4 +-N and TN reached from 45% to 69%. Lastly, as a teaching advice, the Fenton reactor was used in practicing teaching nicely.

  13. Activated sludge treatment by electro-Fenton process: Parameter optimization and degradation mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Rahmani, Ali Reza; Azarian, Ghasem; Berizi, Zohreh [Hamadan University of Medical Sciences, Hamadan (Iran, Islamic Republic of); Nematollahi, Davood [Bu-Ali-Sina University, Hamadan (Iran, Islamic Republic of); Godini, Kazem [Ilam University of Medical Sciences, Ilam (Iran, Islamic Republic of)

    2015-08-15

    This study was conducted to evaluate the mineralization of activated sludge (MAS) by a facile and environmentally friendly electro-Fenton process (EFP). The effects of initial H{sub 2}O{sub 2} concentration, pH value, applied current density and operating time on MAS through determining the removal rate of chemical oxygen demand (COD) and total coliform (TC) were studied. 72% of COD was removed by indirect oxidation double-mediated based on the electro- generation of hydroxyl radical and active chlorine, under the following optimum conditions: 127mmol L{sup -}1 of hydrogen peroxide, pH=3.0, 10 mA cm{sup -}2 of DC current, 120min of operating time, and 0.22mol L{sup -}1 of NaCl as the supporting electrolyte. Only in 10 min and pH 3.0 approximately 100% of TC was removed. The findings indicated that EFP can be applied efficiently for MAS by selecting appropriate operating conditions. The bottom line is that the process is entirely effective owing to the application of green oxidants (hydroxyl radical and active chlorine) and lack of being influenced by environmental situations, which can be introduced as an alternative to current conventional methods.

  14. Activated sludge treatment by electro-Fenton process: Parameter optimization and degradation mechanism

    International Nuclear Information System (INIS)

    Rahmani, Ali Reza; Azarian, Ghasem; Berizi, Zohreh; Nematollahi, Davood; Godini, Kazem

    2015-01-01

    This study was conducted to evaluate the mineralization of activated sludge (MAS) by a facile and environmentally friendly electro-Fenton process (EFP). The effects of initial H 2 O 2 concentration, pH value, applied current density and operating time on MAS through determining the removal rate of chemical oxygen demand (COD) and total coliform (TC) were studied. 72% of COD was removed by indirect oxidation double-mediated based on the electro- generation of hydroxyl radical and active chlorine, under the following optimum conditions: 127mmol L - 1 of hydrogen peroxide, pH=3.0, 10 mA cm - 2 of DC current, 120min of operating time, and 0.22mol L - 1 of NaCl as the supporting electrolyte. Only in 10 min and pH 3.0 approximately 100% of TC was removed. The findings indicated that EFP can be applied efficiently for MAS by selecting appropriate operating conditions. The bottom line is that the process is entirely effective owing to the application of green oxidants (hydroxyl radical and active chlorine) and lack of being influenced by environmental situations, which can be introduced as an alternative to current conventional methods.

  15. Efficient mineralization of the antibiotic trimethoprim by solar assisted photoelectro-Fenton process driven by a photovoltaic cell.

    Science.gov (United States)

    Zhang, Yanyu; Wang, Aimin; Tian, Xiujun; Wen, Zhenjun; Lv, Hanjiao; Li, Desheng; Li, Jiuyi

    2016-11-15

    In this study, a novel self-sustainable solar assisted photoelectro-Fenton (SPEF) system driven by a solar photovoltaic cell was developed for the efficient mineralization of antibiotic trimethoprim (TMP) in water. A comparative degradation of 200mgL(-1) TMP by RuO2/Ti anodic oxidation (AO), anodic oxidation with H2O2 electrogeneration (AO-H2O2), electro-Fenton (EF) and SPEF was investigated. SPEF was proved to exhibit the highest oxidation power, i.e., more than 80% TOC was removed after 360min SPEF treatment of 200mgL(-1) of TMP under optimal conditions at pH 3.0, 1.0mM Fe(2+) and 18mAcm(-2). Influences of current density, pH, initial Fe(2+) and initial TMP concentration on SPEF process were also studied. Ten aromatic intermediates generated from hydroxylation, carbonylation and demethylation reactions were identified using UPLC-QTOF-MS/MS system during the SPEF treatment, together with three carboxylic acids (oxamic, oxalic and formic acids) and two inorganic ions (NH4(+) and NO3(-)) measured. Therefore, a reasonable pathway of TMP degradation in SPEF process was proposed. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Decolorization of C.I. Acid Blue 9 solution by UV/Nano-TiO{sub 2}, Fenton, Fenton-like, electro-Fenton and electrocoagulation processes: A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Khataee, A.R. [Water and Wastewater Treatment Research Laboratory, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)], E-mail: a_khataee@tabrizu.ac.ir; Vatanpour, V. [Water and Wastewater Treatment Research Laboratory, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)], E-mail: vahidvatanpoor@yahoo.com; Amani Ghadim, A.R. [Water and Wastewater Treatment Research Laboratory, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)], E-mail: a.r_amani@yahoo.com

    2009-01-30

    This study makes a comparison between UV/Nano-TiO{sub 2}, Fenton, Fenton-like, electro-Fenton (EF) and electrocoagulation (EC) treatment methods to investigate the removal of C.I. Acid Blue 9 (AB9), which was chosen as the model organic contaminant. Results indicated that the decolorization efficiency was in order of Fenton > EC > UV/Nano-TiO{sub 2} > Fenton-like > EF. Desired concentrations of Fe{sup 2+} and H{sub 2}O{sub 2} for the abatement of AB9 in the Fenton-based processes were found to be 10{sup -4} M and 2 x 10{sup -3} M, respectively. In the case of UV/Nano-TiO{sub 2} process, we have studied the influence of the basic photocatalytic parameters such as the irradiation time, pH of the solution and amount of TiO{sub 2} nanoparticles on the photocatalytic decolorization efficiency of AB9. Accordingly, it could be stated that the complete removal of color, after selecting desired operational parameters could be achieved in a relatively short time, about 25 min. Our results also revealed that the most effective decomposition of AB9 was observed with 150 mg/l of TiO{sub 2} nanoparticles in acidic condition. The effect of operational parameters including current density, initial pH and time of electrolysis were studied in electrocoagulation process. The results indicated that for a solution of 20 mg/l AB9, almost 98% color were removed, when the pH was about 6, the time of electrolysis was 8 min and the current density was approximately 25 A/m{sup 2} in electrocoagulation process.

  17. Decolorization of C.I. Acid Blue 9 solution by UV/Nano-TiO2, Fenton, Fenton-like, electro-Fenton and electrocoagulation processes: A comparative study

    International Nuclear Information System (INIS)

    Khataee, A.R.; Vatanpour, V.; Amani Ghadim, A.R.

    2009-01-01

    This study makes a comparison between UV/Nano-TiO 2 , Fenton, Fenton-like, electro-Fenton (EF) and electrocoagulation (EC) treatment methods to investigate the removal of C.I. Acid Blue 9 (AB9), which was chosen as the model organic contaminant. Results indicated that the decolorization efficiency was in order of Fenton > EC > UV/Nano-TiO 2 > Fenton-like > EF. Desired concentrations of Fe 2+ and H 2 O 2 for the abatement of AB9 in the Fenton-based processes were found to be 10 -4 M and 2 x 10 -3 M, respectively. In the case of UV/Nano-TiO 2 process, we have studied the influence of the basic photocatalytic parameters such as the irradiation time, pH of the solution and amount of TiO 2 nanoparticles on the photocatalytic decolorization efficiency of AB9. Accordingly, it could be stated that the complete removal of color, after selecting desired operational parameters could be achieved in a relatively short time, about 25 min. Our results also revealed that the most effective decomposition of AB9 was observed with 150 mg/l of TiO 2 nanoparticles in acidic condition. The effect of operational parameters including current density, initial pH and time of electrolysis were studied in electrocoagulation process. The results indicated that for a solution of 20 mg/l AB9, almost 98% color were removed, when the pH was about 6, the time of electrolysis was 8 min and the current density was approximately 25 A/m 2 in electrocoagulation process

  18. Improvement of COD and color removal from UASB treated poultry manure wastewater using Fenton's oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Yetilmezsoy, Kaan [Department of Environmental Engineering, Yildiz Technical University, 34349 Yildiz, Besiktas, Istanbul (Turkey)], E-mail: yetilmez@yildiz.edu.tr; Sakar, Suleyman [Department of Environmental Engineering, Yildiz Technical University, 34349 Yildiz, Besiktas, Istanbul (Turkey)

    2008-03-01

    The applicability of Fenton's oxidation as an advanced treatment for chemical oxygen demand (COD) and color removal from anaerobically treated poultry manure wastewater was investigated. The raw poultry manure wastewater, having a pH of 7.30 ({+-}0.2) and a total COD of 12,100 ({+-}910) mg/L was first treated in a 15.7 L of pilot-scale up-flow anaerobic sludge blanket (UASB) reactor. The UASB reactor was operated for 72 days at mesophilic conditions (32 {+-} 2 deg. C) in a temperature-controlled environment with three different hydraulic retention times (HRT) of 15.7, 12 and 8.0 days, and with organic loading rates (OLR) between 0.650 and 1.783 kg COD/(m{sup 3} day). Under 8.0 days of HRT, the UASB process showed a remarkable performance on total COD removal with a treatment efficiency of 90.7% at the day of 63. The anaerobically treated poultry manure wastewater was further treated by Fenton's oxidation process using Fe{sup 2+} and H{sub 2}O{sub 2} solutions. Batch tests were conducted on the UASB effluent samples to determine the optimum operating conditions including initial pH, effects of H{sub 2}O{sub 2} and Fe{sup 2+} dosages, and the ratio of H{sub 2}O{sub 2}/Fe{sup 2+}. Preliminary tests conducted with the dosages of 100 mg Fe{sup 2+}/L and 200 mg H{sub 2}O{sub 2}/L showed that optimal initial pH was 3.0 for both COD and color removal from the UASB effluent. On the basis of preliminary test results, effects of increasing dosages of Fe{sup 2+} and H{sub 2}O{sub 2} were investigated. Under the condition of 400 mg Fe{sup 2+}/L and 200 mg H{sub 2}O{sub 2}/L, removal efficiencies of residual COD and color were 88.7% and 80.9%, respectively. Under the subsequent condition of 100 mg Fe{sup 2+}/L and 1200 mg H{sub 2}O{sub 2}/L, 95% of residual COD and 95.7% of residual color were removed from the UASB effluent. Results of this experimental study obviously indicated that nearly 99.3% of COD of raw poultry manure wastewater could be effectively removed by a

  19. Landfill leachate treatment by coagulation/flocculation combined with microelectrolysis-Fenton processes.

    Science.gov (United States)

    Luo, Kun; Pang, Ya; Li, Xue; Chen, Fei; Liao, Xingsheng; Lei, Min; Song, Yong

    2018-02-07

    Landfill leachate was pretreated by chemical flocculation with polyaluminum chloride (PAC) as a flocculant, and subsequently purified by the microelectrolysis-Fenton (MEF) process. Response surface methodology was employed to optimize the MEF process, and the optimal conditions were initial pH 3.20, H 2 O 2 concentration 3.57 g/L, and Fe-C dosage 104.52 g/L. The PAC coagulation combined with MEF processes obtained a superior decontamination performance, and the predicted chemical oxygen demand (COD) and humic acids (HA) removal were respectively 90.27% and 93.79%. The strong fluorescence peak at 425 nm and the trapping experiment showed that [Formula: see text] was generated during MEF, which had a strong oxidation ability to degrade organic recalcitrant pollutants. The ultraviolet-visible spectra and three-dimensional excitation-emission matrices spectra (3D-EEMs) indicated that PAC coagulation could preferentially remove protein-like substances, while the MEF process was effective in destructing organic recalcitrant pollutants, especially humic-like and fulvic-like substances.

  20. Terbium(III) ions as sensitizers of oxidation of indole and its derivatives in Fenton system

    Energy Technology Data Exchange (ETDEWEB)

    Kaczmarek, Małgorzata, E-mail: mkaczmar@amu.edu.pl; Staninski, Krzysztof

    2017-03-15

    Oxidation of indole and its derivatives in the Fenton system as a source of oxidising agents, in the presence of terbium(III) ions was studied by chemiluminescence methods to get the kinetic curves of emission decay and spectral distributions of chemiluminescence. Terbium(III) ions acted as a sensitizer of the mixtures Tb(III)-Fe(II)/Fe(III)-H{sub 2}O{sub 2}-indole or its derivative (tryptophan, tryptamine, indole-3-acetic acid and indole-3-acetyl aspartic acid). For the above indolic compounds, linear dependencies of integrated intensity of chemiluminescence on concentration of indolic compound in water and in water-acetonitrile solution were obtained. The limits of detection (LOD) and quantification (LOQ) of the indolic compounds studied were found to be by one or two orders of magnitude lower in the system with terbium(III) ions than without them. - Highlights: • Chemiluminescence emitted on oxidation of indolic compounds in Fenton system. • Tb (III) ions as sensitizers of indolic compounds oxidation in solutions. • Linear relations between CL intensity and indolic compound concentration.

  1. Integrating Fenton's process and ion exchange for olive mill wastewater treatment and iron recovery.

    Science.gov (United States)

    Reis, Patrícia M; Martins, Pedro J M; Martins, Rui C; Gando-Ferreira, Licínio M; Quinta-Ferreira, Rosa M

    2018-02-01

    A novel integrated methodology involving Fenton's process followed by ion exchange (IE) was proposed for the treatment of olive mill wastewater. Fenton's process was optimized and it was able to remove up to 81% of chemical oxygen demand when pH 3.5, reaction time 1 h, [Fe 2+ ] = 50 mg L -1 and [Fe 2+ ]/[H 2 O 2 ] = 0.002 were applied. In spite of the potential of this treatment approach, final iron removal from the liquid typically entails pH increase and iron sludge production. The integration of an IE procedure using Lewatit TP 207 resin was found to be able to overcome this important environmental shortcoming. The resin showed higher affinity toward Fe 3+ than to Fe 2+ . However, the iron removal efficiency of an effluent coming from Fenton's was independent of the type of the initial iron used in the process. The presence of organic matter had no significant effect over the resin iron removal efficiency. Even if some efficiency decrease was observed when a high initial iron load was applied, the adsorbent mass quantity can be easily adapted to reach the desired iron removal. The use of IE is an interesting industrial approach able to surpass Fenton's peroxidation drawback and will surely boost its full-scale application in the treatment of bio-refractory effluents.

  2. Integrating the Fenton's Process with Biofiltration by to Reduce Chemical Oxygen Demand of Winery Effluents.

    Science.gov (United States)

    Pipolo, Marco; Martins, Rui C; Quinta-Ferreira, Rosa M; Costa, Raquel

    2017-03-01

    The discharge of poorly decontaminated winery wastewater remains a serious environmental problem in many regions, and the industry is welcoming improved treatment methods. Here, an innovative decontamination approach integrating Fenton's process with biofiltration by Asian clams is proposed. The potential of this approach was assessed at the pilot scale using real effluent and by taking an actual industrial treatment system as a benchmark. Fenton peroxidation was observed to remove 84% of the effluent's chemical oxygen demand (COD), reducing it to 205 mg L. Subsequent biofiltration decreased the effluent's COD to approximately zero, well below the legal discharge limit of 150 mg L, in just 3 d. The reduction of the effluent's organic load through Fenton's process did not decrease its toxicity toward , but the effluent was much less harmful after biofiltration. The performance of the treatment proposed exceeded that of the integrated Fenton's process-sequencing batch reactor design implemented in the winery practice, where a residence time of around 10 d in the biological step typically results in 80 to 90% of COD removal. The method proposed is effective and compatible with typical winery budgets and potentially contributes to the management of a nuisance species. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  3. Characterization of dissolved organic matter in landfill leachate during the combined treatment process of air stripping, Fenton, SBR and coagulation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, ZhiPing, E-mail: liulqs@163.com [Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045 (China); Faculty of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400020 (China); Wu, WenHui; Shi, Ping [Faculty of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400020 (China); Guo, JinSong [Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400045 (China); Cheng, Jin [Faculty of Urban Construction and Environmental Engineering, Chongqing University, Chongqing 400020 (China)

    2015-07-15

    Highlights: • DOM fractions spectra analysis during the whole treatment process. • Efficient method was achieved to remove organic matters in landfill leachate. • Molecular weight distribution and fractions were discussed. - Abstract: A combined treatment process of air stripping + Fenton + sequencing batch reactor (SBR)+ coagulation was performed to remove the pollutants in landfill leachate. Molecular weight (MW) distribution and fractions of dissolved organic matter (DOM) were discussed to study the characteristics. The experiment showed that the removal rate of chemical oxygen demand (COD), five day biological oxygen demand (BOD{sub 5}) and ammonia nitrogen (NH{sub 3}−N) by the combined process were 92.8%, 87.8% and 98.0%, respectively. Humic acid (HA) and fulvic acid (FA) were the main fractions in raw leachate with 81.8% of the total COD concentration, while hydrophilic organic matter (HyI) was the dominant fraction in the final effluent of the combined process with 63.5% of the total COD concentration. After the combined treatment process, the removal rate of DOM and fractions HA, FA, HyI were 91.9%, 97.1%, 95.8% and 71.7%, respectively. Organic matters of MW < 2 k and MW > 100 k were removed with 90.5% and 97.9% COD concentration after the treatment. The ultraviolet–visible spectra (UV–vis), Fourier transform infrared spectra (FTIR) and three-dimensional excitation-emission matrices spectra (EEMs) indicated that benzene materials and phenol compounds were preferentially removed in air stripping. High MW matters, aromatic rings, conjugated moieties and some functional groups were mainly removed by Fenton. While small MW fractions, carboxylic acids, alcohols and protein-like materials were preferentially biodegraded via SBR. Fulvic-like and humic-like materials were mainly destroyed via Fenton oxidation and coagulation.

  4. Microwave enhanced Fenton-like process for the treatment of high concentration pharmaceutical wastewater

    International Nuclear Information System (INIS)

    Yang Yu; Wang Peng; Shi Shujie; Liu Yuan

    2009-01-01

    This paper explored a novel process for wastewater treatment, i.e. microwave enhanced Fenton-like process. This novel process was introduced to treat high concentration pharmaceutical wastewater with initial COD loading of 49,912.5 mg L -1 . Operating parameters were investigated and the optimal condition included as follows: microwave power was 300 W, radiation time was 6 min, initial pH was 4.42, H 2 O 2 dosage was 1300 mg L -1 and Fe 2 (SO 4 ) 3 dosage was 4900 mg L -1 , respectively. Within the present experimental condition used, the COD removal and UV 254 removal reached to 57.53% and 55.06%, respectively, and BOD 5 /COD was enhanced from 0.165 to 0.470. The variation of molecular weight distribution indicated that both macromolecular substances and micromolecular substances were eliminated quite well. The structure of flocs revealed that one ferric hydrated ion seemed to connect with another ferric hydrated ion and/or organic compound molecule to form large-scale particles by means of van der waals force and/or hydrogen bond. Subsequently, these particles aggregated to form flocs and settled down. Comparing with traditional Fenton-like reaction and conventional heating assisted Fenton-like reaction, microwave enhanced Fenton-like process displayed superior treatment efficiency. Microwave was in favor of improving the degradation efficiency, the settling quality of sludge, as well as reducing the yield of sludge and enhancing the biodegradability of effluent. Microwave enhanced Fenton-like process is believed to be a promising treatment technology for high concentration and biorefractory wastewater.

  5. p-Nitrophenol degradation by Fenton's oxidation in a bubble column reactor.

    Science.gov (United States)

    Rodrigues, Carmen S D; Borges, Ricardo A C; Lima, Vanessa N; Madeira, Luis M

    2018-01-15

    This paper reports on a study of the oxidation of p-nitrophenol (PNP) in a bubble column reactor (BCR). The use of the air stream aimed to provide perfect mixing in the liquid phase, which was successfully achieved and checked experimentally; there were no concentration gradients along the column, even at the lowest air flow rate used (Q = 1 mL/min at room temperature and atmospheric pressure). The effect of the operating variables was assessed, and a total reduction of PNP was reached, as well as mineralization of 49.2%, oxidant consumption of 90.3%, and with an efficiency of use - η H2O2 - of 0.09 mg C/mg H 2 O 2 , under the best operating conditions found - Q = 1 mL/min, [H 2 O 2 ] = 1.6 g/L, [Fe 2+ ] = 80 mg/L, pH = 3.0 and T = 22-24 °C - (after 120 min of reaction). Following this, various strategies were developed for improving the mineralization rate; it was found that the addition of H 2 O 2 every 5 min and readjusting the pH after 30 min of reaction allow the attainment of a much higher TOC removal (75.1%) and efficiency of oxidant use (η H2O2  = 0.17 mg C/mg H 2 O 2 ) with less oxidant. A reaction mechanism was proposed, based on intermediates identified that include p-nitrocatechol - PNC, p-benzoquinone - PB, hydroquinone - HQ - and carboxylic acids (oxalic, maleic and fumaric). Since the performance achieved in the BCR was good, and very similar to that obtained in a conventional batch reactor, it was possible to verify the efficacy of carrying out the Fenton process in this reactor configuration, which in our future work will focus on the treatability of industrial effluents. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Reaction mechanisms and evaluation of effective process operation for catalytic oxidation and coagulation by ferrous solution and hydrogen peroxide

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.H.; Moon, H.J.; Kim, Y.M. [Dept. of Environmental Engineering, Sangmyung Univ., Cheonan (Korea); Bae, W.K. [Dept. of Civil and Environmental Engineering, Hanyang Univ., Ansan, Kyounggi (Korea)

    2003-07-01

    This research was carried out to evaluate the removal efficiencies of COD{sub cr} and colour for the dyeing wastewater by ferrous solution and the different dosage of H{sub 2}O{sub 2} in Fenton process. In the case of H{sub 2}O{sub 2} divided dosage, 7:3 was more effective than 3:7 to remove COD{sub cr} and colour. The results showed that COD was mainly removed by Fenton coagulation, where the ferric ions are formed in the initial step of Fenton reaction. On the other hand colour was removed by Fenton oxidation rather than Fenton coagulation. This paper also aims at pursuing to investigate the effective removal mechanisms using ferrous ion coagulation, ferric ion coagulation and Fenton oxidation process. The removal mechanism of COD{sub cr} and colour was mainly coagulation by ferrous ion, ferric ion and Fenton oxidation. The removal efficiencies were dependent on the ferric ion amount at the beginning of the reaction. However the final removal efficiency of COD and colour was in the order of Fenton oxidation, ferric ion coagulation and ferrous ion coagulation. The reason of the highest removal efficiency by Fenton oxidation can be explained by the chain reactions with ferrous solution, ferric ion and hydrogen peroxide. (orig.)

  7. Study of the removal of metronidazole from aqueous solutions using Electro/ Fenton process and graphite and iron electrodes

    Directory of Open Access Journals (Sweden)

    Bahram Kamarehie

    2018-04-01

    Conclusion: The Electro-Fenton process can effectively remove metronidazole from aquatic solutions in environmentally convenient conditions. This process can be used as an efficient method for removing other persistent pollutants from the environment.

  8. Oxidative degradation of phenols in sono-Fenton-like systems upon high-frequency ultrasound irradiation

    Science.gov (United States)

    Aseev, D. G.; Sizykh, M. R.; Batoeva, A. A.

    2017-12-01

    The kinetics of oxidative degradation of phenol and chlorophenols upon acoustic cavitation in the megahertz range (1.7 MHz) is studied experimentally in model systems, and the involvement of in situ generated reactive oxygen species (ROSs) is demonstrated. The phenols subjected to high frequency ultrasound (HFUS) are ranked in terms of their rate of conversion: 2,4,6-trichlorophenol > 2,4-dichlorophenol 2-chlorophenol > 4-chlorophenol phenol. Oxidative degradation upon HFUS irradiation is most efficient at low concentrations of pollutants, due to the low steady-state concentrations of the in situ generated ROSs. A dramatic increase is observed in the efficiency of oxidation in several sonochemical oxidative systems (HFUS in combination with other chemical oxidative factors). The system with added Fe2+ (a sono-Fenton system) derives its efficiency from hydrogen peroxide generated in situ as a result of the recombination of OH radicals. The S2O8 2-/Fe2+/HFUS system has a synergetic effect on substrate oxidation that is attributed to a radical chain mechanism. In terms of the oxidation rates, degrees of conversion, and specific energy efficiencies of 4-chlorophenol oxidation based on the amount of oxidized substance per unit of expended energy the considered sonochemical oxidative systems form the series HFUS < S2O8 2-/HFUS < S2O8 2-/Fe2+/HFUS.

  9. Kinetic Modeling of a Heterogeneous Fenton Oxidative Treatment of Petroleum Refining Wastewater

    Science.gov (United States)

    Basheer Hasan, Diya'uddeen; Abdul Raman, Abdul Aziz; Wan Daud, Wan Mohd Ashri

    2014-01-01

    The mineralisation kinetics of petroleum refinery effluent (PRE) by Fenton oxidation were evaluated. Within the ambit of the experimental data generated, first-order kinetic model (FKM), generalised lumped kinetic model (GLKM), and generalized kinetic model (GKM) were tested. The obtained apparent kinetic rate constants for the initial oxidation step (k 2′), their final oxidation step (k 1′), and the direct conversion to endproducts step (k 3′) were 10.12, 3.78, and 0.24 min−1 for GKM; 0.98, 0.98, and nil min−1 for GLKM; and nil, nil, and >0.005 min−1 for FKM. The findings showed that GKM is superior in estimating the mineralization kinetics. PMID:24592152

  10. p-Nitrophenol degradation by electro-Fenton process: Pathway, kinetic model and optimization using central composite design.

    Science.gov (United States)

    Meijide, J; Rosales, E; Pazos, M; Sanromán, M A

    2017-10-01

    The chemical process scale-up, from lab studies to industrial production, is challenging and requires deep knowledge of the kinetic model and the reactions that take place in the system. This knowledge is also useful in order to be employed for the reactor design and the determination of the optimal operational conditions. In this study, a model substituted phenol such as p-nitrophenol was degraded by electro-Fenton process and the reaction products yielded along the treatment were recorded. The kinetic model was developed using Matlab software and was based on main reactions that occurred until total mineralization which allowed predicting the degradation pathway under this advanced oxidation process. The predicted concentration profiles of p-nitrophenol, their intermediates and by-products in electro-Fenton process were validated with experimental assays and the results were consistent. Finally, based on the developed kinetic model the degradation process was optimized using central composite design taking as key parameters the ferrous ion concentration and current density. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Removal of residual contaminants in petroleum-contaminated soil by Fenton-like oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Lu Mang [School of Material Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen, 333001, Jiangxi Province (China); State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China); Zhang Zhongzhi, E-mail: zzzhang1955@hotmail.com [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China); Qiao Wei; Guan Yueming; Xiao Meng; Peng Chong [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China)

    2010-07-15

    The degradation of bioremediation residues by hydrogen peroxide in petroleum-contaminated soil was investigated at circumneutral pH using a Fenton-like reagent (ferric ion chelated with EDTA). Batch tests were done on 20 g soil suspended in 60 mL aqueous solution containing hydrogen peroxide and Fe{sup 3+}-EDTA complex under constant stirring. A slurry reactor was used to treat the soil based on the optimal reactant conditions. Contaminants were characterized by Fourier transform infrared spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry. The results showed that the optimal treatment condition was: the molar ratio of hydrogen peroxide to iron = 200:1, and pH 7.0. Under the optimum condition, total dichloromethane-extractable organics were reduced from 14,800 to 2300 mg kg{sup -1} soil when the accumulative H{sub 2}O{sub 2} dosage was 2.45 mol kg{sup -1} soil during the reactor treatment. Abundance of viable cells was lower in incubated Fenton-like treated soil than in untreated soil. Oxidation of contaminants produced remarkable compositional and structural modifications. A fused ring compound, identified as C{sub 34}H{sub 38}N{sub 1}, was found to exhibit the greatest resistance to oxidation.

  12. Using iron-loaded sepiolite obtained by adsorption as a catalyst in the electro-Fenton oxidation of Reactive Black 5.

    Science.gov (United States)

    Iglesias, O; Fernández de Dios, M A; Pazos, M; Sanromán, M A

    2013-09-01

    This study explores the possibility of using iron-loaded sepiolite, obtained by recovering iron from polluted water, as a catalyst in the electro-Fenton oxidation of organic pollutants in textile effluents. The removal of iron ions from aqueous solution by adsorption on sepiolite was studied in batch tests at iron concentrations between 100 and 1,000 ppm. Electro-Fenton experiments were carried out in an electrochemical cell with a working volume of 0.15 L, an air flow of 1 L/min, and 3 g of iron-loaded sepiolite. An electric field was applied using a boron-doped diamond anode and a graphite sheet cathode connected to a direct current power supply with a constant potential drop. Reactive Black 5 (100 mg/L) was selected as the model dye. The adsorption isotherms proved the ability of the used adsorbent. The removal of the iron ion by adsorption on sepiolite was in the range of 80-100 % for the studied concentration range. The Langmuir and Freundlich isotherms were found to be applicable in terms of the relatively high regression values. Iron-loaded sepiolite could be used as an effective heterogeneous catalyst for the degradation of organic dyes in the electro-Fenton process. Successive batch processes were performed at optimal working conditions (5 V and pH 2). The results indicate the suitability of the proposed combined process, adsorption to iron remediation followed by the application of the obtained iron-loaded sepiolite to the electro-Fenton technique, to oxidize polluted effluents.

  13. ADVANCED OXIDATION PROCESSES (AOX) TEXTILE WASTEWATER

    OpenAIRE

    Salas C., G.

    2014-01-01

    Advanced Oxidation Processes (AOX) are based on the in situ generation of hydroxyradicals (·OH), which have a high oxidation potential. In the case of Fenton processes !he generation of hydroxy radicals takes place by the combination of an oxidation agent (H202) with a catalyst (Fe(II)). These radicals are not selective and they react very fast with the organic matter,being able to oxidize a high variety of organic compounds. This property allows the degradation of pollutants into more biodeg...

  14. Treatment of industrial wastewater effluents using hydrodynamic cavitation and the advanced Fenton process.

    Science.gov (United States)

    Chakinala, Anand G; Gogate, Parag R; Burgess, Arthur E; Bremner, David H

    2008-01-01

    For the first time, hydrodynamic cavitation induced by a liquid whistle reactor (LWR) has been used in conjunction with the advanced Fenton process (AFP) for the treatment of real industrial wastewater. Semi-batch experiments in the LWR were designed to investigate the performance of the process for two different industrial wastewater samples. The effect of various operating parameters such as pressure, H2O2 concentration and the initial concentration of industrial wastewater samples on the extent of mineralization as measured by total organic carbon (TOC) content have been studied with the aim of maximizing the extent of degradation. It has been observed that higher pressures, sequential addition of hydrogen peroxide at higher loadings and lower concentration of the effluent are more favourable for a rapid TOC mineralization. In general, the novel combination of hydrodynamic cavitation with AFP results in about 60-80% removal of TOC under optimized conditions depending on the type of industrial effluent samples. The combination described herein is most useful for treatment of bio-refractory materials where the diminution in toxicity can be achieved up to a certain level and then conventional biological oxidation can be employed for final treatment. The present work is the first to report the use of a hydrodynamic cavitation technique for real industrial wastewater treatment.

  15. Enhanced heterogeneous photo-Fenton process modified by magnetite and EDDS: BPA degradation.

    Science.gov (United States)

    Huang, Wenyu; Luo, Mengqi; Wei, Chaoshuai; Wang, Yinghui; Hanna, Khalil; Mailhot, Gilles

    2017-04-01

    In this research, magnetite and ethylenediamine-N,N'-disuccinic acid (EDDS) are used in a heterogeneous photo-Fenton system in order to find a new way to remove organic contaminants from water. Influence of different parameters including magnetite dosage, EDDS concentration, H 2 O 2 concentration, and pH value were evaluated. The effect of different radical species including HO · and HO 2 · /O 2 ·- was investigated by addition of different scavengers into the system. The addition of EDDS improved the heterogeneous photo-Fenton degradation of bisphenol A (BPA) through the formation of photochemically efficient Fe-EDDS complex. This effect is dependent on the H 2 O 2 and EDDS concentrations and pH value. The high performance observed at pH 6.2 could be explained by the ability of O 2 ·- to generate Fe(II) from Fe(III) species reduction. GC-MS analysis suggested that the cleavage of the two benzene rings is the first degradation step followed by oxidation leading to the formation of the benzene derivatives. Then, the benzene ring was opened due to the attack of HO · radicals producing short-chain organic compounds of low molecular weight like glycerol and ethylene glycol. These findings regarding the capability of EDDS/magnetite system to promote heterogeneous photo-Fenton oxidation have important practical implications for water treatment technologies.

  16. Effects on temperature and acidic pre-treatment on Fenton-driven oxidation of MTBE-spent granular activated carbon

    Science.gov (United States)

    Temperature-dependent mechanisms in the Fenton-driven chemical oxidation of methyl tert-butyl ether (MTBE)-spent granular activated carbon (GAC) was investigated. Prior to iron (Fe) amendment to the GAC, acid-treatment altered the surface chemistry of the GAC and lowered the p...

  17. Effects of Temperature and Acidic Pre-Treatment on Fenton-Driven Oxidation of MTBE-Spent Granular Activated Carbon

    Science.gov (United States)

    Temperature-dependent mechanisms in the Fenton-driven chemical oxidation of methyl tert-butyl ether (MTBE)-spent granular activated carbon (GAC) was investigated. Prior to iron (Fe) amendment to the GAC, acid-treatment altered the surface chemistry of the GAC and lowered the pH ...

  18. Humic Acid Degradation via Solar Photo-Fenton Process in Aqueous Environment

    Directory of Open Access Journals (Sweden)

    Seyed Ali Sajjadi

    2015-08-01

    Full Text Available Control of mutagenic and carcinogenic disinfection by-products, particularly Trihalomethanes (THMs and Halo Acetic Acids (HAAs in water treatment process is critical, due to their adverse effects on human health. Generally, reducing the toxicity of these by-products hinges on prior removal of the precursor materials, such as Humic Acid (HA in drinking water. This study was conducted to investigate the role of some parameters that could affect the removal of HA, including HA (5 and 10 ppm and H2O2 (20, 40, 60, and 80 ppm initial concentrations, Iron (II, sulfate heptahydrate dosage (4, 8, 12, and 16 ppm, pH (2, 3, 4 and 5, Oxidation time (5, 10, 15 and 30 min, and Sunlight levels (322±13 kWm-2. To accelerate the process of HA removal, the Solar Photo-Fenton (SPF process was employed by direct irradiation of converged sunlight in a Parabolic Trough Collectors (PTC, with 3m2 effective area. HA levels were measured via quantifying Dissolved Organic Carbon (DOC concentrations by means of a TOC Analyzer method. The results showed that the SPF process is under control of the Fe & H2O2 ratio, the Fe2+ dosage and especially the pH quantity. In optimal condition, (pH: 4, oxidation time: 30min, initial HA levels: 50 ppm, H2O2 concentrations: 20 ppm Fe+2 levels: 4 ppm, the study found more than 98% DOC removal. In conclusion, the SPF, as an economically effective technique, could be applied for the removal of HA in aqueous environments.

  19. Development of a trickle bed reactor of electro-Fenton process for wastewater treatment

    Energy Technology Data Exchange (ETDEWEB)

    Lei, Yangming [Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 401122 (China); School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Liu, Hong, E-mail: liuhong@cigit.ac.cn [Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 401122 (China); Shen, Zhemin, E-mail: zmshen@sjtu.edu.cn [School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Wang, Wenhua [School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2013-10-15

    Highlights: • An electrochemical trickle bed reactor was composed of C-PTFE-coated graphite chips. • The trickle bed reactor had a high H{sub 2}O{sub 2} production rate in a dilute electrolyte. • An azo dye was effectively decomposed by the electro-Fenton process in the reactor. -- Abstract: To avoid electrolyte leakage and gas bubbles in the electro-Fenton (E-Fenton) reactors using a gas diffusion cathode, we developed a trickle bed cathode by coating a layer composed of carbon black and polytetrafluoroethylene (C-PTFE) onto graphite chips instead of carbon cloth. The trickle bed cathode was optimized by single-factor and orthogonal experiments, in which carbon black, PTFE, and a surfactant were considered as the determinant of the performance of graphite chips. In the reactor assembled by the trickle bed cathode, H{sub 2}O{sub 2} was generated with a current of 0.3 A and a current efficiency of 60%. This performance was attributed to the fine distribution of electrolyte and air, as well as the effective oxygen transfer from the gas phase to the electrolyte–cathode interface. In terms of H{sub 2}O{sub 2} generation and current efficiency, the developed trickle bed reactor had a performance comparable to that of the conventional E-Fenton reactor using a gas diffusion cathode. Further, 123 mg L{sup −1} of reactive brilliant red X-3B in aqueous solution was decomposed in the optimized trickle bed reactor as E-Fenton reactor. The decolorization ratio reached 97% within 20 min, and the mineralization reached 87% within 3 h.

  20. Development of a trickle bed reactor of electro-Fenton process for wastewater treatment

    International Nuclear Information System (INIS)

    Lei, Yangming; Liu, Hong; Shen, Zhemin; Wang, Wenhua

    2013-01-01

    Highlights: • An electrochemical trickle bed reactor was composed of C-PTFE-coated graphite chips. • The trickle bed reactor had a high H 2 O 2 production rate in a dilute electrolyte. • An azo dye was effectively decomposed by the electro-Fenton process in the reactor. -- Abstract: To avoid electrolyte leakage and gas bubbles in the electro-Fenton (E-Fenton) reactors using a gas diffusion cathode, we developed a trickle bed cathode by coating a layer composed of carbon black and polytetrafluoroethylene (C-PTFE) onto graphite chips instead of carbon cloth. The trickle bed cathode was optimized by single-factor and orthogonal experiments, in which carbon black, PTFE, and a surfactant were considered as the determinant of the performance of graphite chips. In the reactor assembled by the trickle bed cathode, H 2 O 2 was generated with a current of 0.3 A and a current efficiency of 60%. This performance was attributed to the fine distribution of electrolyte and air, as well as the effective oxygen transfer from the gas phase to the electrolyte–cathode interface. In terms of H 2 O 2 generation and current efficiency, the developed trickle bed reactor had a performance comparable to that of the conventional E-Fenton reactor using a gas diffusion cathode. Further, 123 mg L −1 of reactive brilliant red X-3B in aqueous solution was decomposed in the optimized trickle bed reactor as E-Fenton reactor. The decolorization ratio reached 97% within 20 min, and the mineralization reached 87% within 3 h

  1. Degradation of phenol with using of Fenton-like Processes from water

    Directory of Open Access Journals (Sweden)

    Ahmad Reza Yazdanbakhsh

    2015-08-01

    Full Text Available Phenol is one of the serious pollutants from the chemical and petrochemical industries. This pollutant due to its convoluted structure is resistant to biodegradation. One of the methods that are useful to remove this pollutant is advanced oxidation (AOP. A laboratory scale study was done on a synthetic wastewater containing phenol. All experiments were done in batch conditions and effect of variables pH, amount of hydrogen peroxide, iron dosage, contact time and an initial concentration on the phenol removal were tested. The remaining phenol concentration was evaluated using the DR-5000 device. In order to effect of these parameters, the experiment was performance at pH 2 to 6, 5 to 45 ml/ml of peroxide, and time of 5 to 60 minutes with 2 to 15 g/ml iron (Fe˚. The optimum pH, the ratio of hydrogen, Fe˚and time were 3, 15 ml, 8g and 5 minutes respectively. Chemical oxygen demand (COD index was chosen as the parameter for evaluation in this study. Result showed that mineralization of phenol was not complete. The COD removal efficiency was obtained 71%. According to the results of this study, Fenton-like process can be used for conversion organic resistant compounds to other compounds with lower toxicity.

  2. A comparative study for treatment of white liquor by different applications of Fenton process

    Directory of Open Access Journals (Sweden)

    Mehmet Faik Sevimli

    2014-12-01

    Full Text Available In this paper, the treatability of white liquor by conventional (CFP, modified (MFP and electro-Fenton oxidation processes (EFP was investigated depending on the COD parameter. Based on the experimental results, up to 62.4%, 58.4% and 54.9% COD removals by the CFP, MFP and EFP were achieved, respectively. It was observed that adjustment of initial pH to acidic values is not required in the CFP. The optimal operational conditions were found to be [Fe2+] = 500 mg/L, [H2O2] = 1000 mg/L at pH 7.3 (original pH in the CFP, [Fe0] = 1250 mg/L, [H2O2] = 1000 mg/L at pH 3 in the MFP, and I = 1.0 A, [H2O2] = 1500 mg/L at pH 3 in the EFP, respectively. As a result, the CFP has been determined as a more efficient alternative treatment method.

  3. Decolorization and mineralization of Diarylide Yellow 12 (PY12) by photo-Fenton process: the Response Surface Methodology as the optimization tool.

    Science.gov (United States)

    GilPavas, Edison; Dobrosz-Gómez, Izabela; Gómez-García, Miguel Ángel

    2012-01-01

    The Response Surface Methodology (RSM) was applied as a tool for the optimization of the operational conditions of the photo-degradation of highly concentrated PY12 wastewater, resulting from a textile industry located in the suburbs of Medellin (Colombia). The Box-Behnken experimental Design (BBD) was chosen for the purpose of response optimization. The photo-Fenton process was carried out in a laboratory-scale batch photo-reactor. A multifactorial experimental design was proposed, including the following variables: the initial dyestuff concentration, the H(2)O(2) and the Fe(+2) concentrations, as well as the UV wavelength radiation. The photo-Fenton process performed at the optimized conditions resulted in ca. 100% of dyestuff decolorization, 92% of COD and 82% of TOC degradation. A kinetic study was accomplished, including the identification of some intermediate compounds generated during the oxidation process. The water biodegradability reached a final DBO(5)/DQO = 0.86 value.

  4. NATURAL IRON OXIDE AS A HETEROGENEOUS PHOTO-FENTON-LIKE CATALYST FOR THE DEGRADATION OF 1-NAPHTHOL UNDER ARTIFICIAL AND SOLAR LIGHT

    Directory of Open Access Journals (Sweden)

    L MAMMERI

    2014-07-01

    Full Text Available A heterogeneous photo-Fenton-like degradation process of 1-naphthol (1-NP promoted by natural iron oxide (NIO in the presence of H2O2 was studied under artificial (365 nm and solar irradiation. This is an important reaction for the environment since both H2O2 and iron oxides are common constituents of natural waters. Furthermore, iron oxides function as catalysts in chemical oxidation processes used with H2O2 for treatment of contaminated waters. The NIO used in this study was characterized by X-ray diffraction (XRD, X-ray fluorescence and Brunauer–Emmett–Teller (BET methods. The results show that the NIO is a composite material that contains predominantly crystalline hematite particales (Fe2O3. The Fe2O3 in NIO was able to initiate the Fenton-like and photo-Fenton-like reactions. The effects of initial pH, catalyst dosage, H2O2 concentration and the wavelength of the light source (UV and solar on the photodegradation of 1-NP were investigated. The optimal content of the NIO was 1 g L-1 and the optimal H2O2 concentration was 10 mM. The degradation could occur efficiently over a wide pH range of 3-8.3. Furthermore, an important effect of light was observed. The photo-oxidation of 1-NP in NIO-H2O2 system under solar light was significantly accelerated in comparison with artificial irradiation at 365 nm.

  5. Influence of anionic surfactant on the process of electro-Fenton decolorized methyl orange.

    Science.gov (United States)

    Ren, B X

    2010-01-01

    The electro-Fenton process has been shown to be very successful to remove dyes from water. However, the influence of other constituents in dyeing industry wastewater, such as Sodium Dodecyl Sulfate (SDS) surfactants, has not been investigated. In this study, the effect of SDS surfactant on the kinetics of Methyl Orange degradation undergoing Electro-Fenton process was investigated. Results show that Methyl Orange degradation rate decreased as SDS concentration (below Critical Micelle Concentration, CMC) increased, which was attributed to the consumption of hydroxyl radicals (( )OH) by surfactants. The kinetics modeling indicates the reaction was the first-order reaction to Methyl Orange even SDS existing. The pseudo first-order rate constants decreased as SDS concentration increased.

  6. Effect of anionic surfactants on the process of Fenton degradation of methyl orange.

    Science.gov (United States)

    Yang, C W; Wang, D

    2009-01-01

    Fenton process has been shown to be very successful to remove dyes from water. However, the influence of other constituents in dyeing industry wastewater, such as Sodium Dodecyl Sulphate (SDS) surfactants, has not been investigated. In this study, the effect of SDS surfactant on the kinetics of Methyl Orange degradation undergoing Fenton process was investigated. Results show that Methyl Orange degradation rate decreased as SDS concentration increased, which was attributed to the consumption of hydroxyl radicals (OH) by surfactants and the formation of Methyl Orange-SDS complex. No evidence was found that the Methyl Orange degradation pathway was affected by the presence of SDS. The kinetics modelling indicates the reaction was the first-order reaction to Methyl Orange.

  7. Reuse of recalcitrant-rich anaerobic effluent as dilution water after enhancement of biodegradability by Fenton processes.

    Science.gov (United States)

    Arimi, Milton M; Zhang, Yongjun; Namango, Saul S; Geißen, Sven-Uwe

    2016-03-01

    Anaerobic digestion is used to treat effluents with a lot of organics, such as molasses distillery wastewater (MDW) which is the effluent of bioethanol production from molasses. The raw MDW requires a lot of dilution water before biodigestion, while the digested MDW has high level of recalcitrants which are problematic for its discharge. This study investigated ferric coagulation, Fenton, Fenton-like (with ferric ions as catalyst) processes and their combinations on the biodegradability of digested MDW. The Fenton and Fenton-like processes after coagulation increased the MDW biodegradability defined by (BOD5/COD) from 0.07 to (0.4-0.6) and saved 50% of H2O2 consumed in the classic Fenton process. The effluent from coagulation coupled to a Fenton-like process was used as dilution water for the raw MDW before the anaerobic digestion. The process was stable with volumetric loading of approx. 2.7 g COD/L/d. It resulted in increased overall biogas recovery and significantly decreased the demand for the dilution water. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Treatment of landfill leachate using a combined stripping, Fenton, SBR, and coagulation process

    International Nuclear Information System (INIS)

    Guo Jinsong; Abbas, Abdulhussain A.; Chen Youpeng; Liu Zhiping; Fang Fang; Chen Peng

    2010-01-01

    The leachate from Changshengqiao landfill (Chongqing, China) was characterized and submitted to a combined process of air stripping, Fenton, sequencing batch reactor (SBR), and coagulation. Optimum operating conditions for each process were identified. The performance of the treatment was assessed by monitoring the removal of organic matter (COD and BOD 5 ) and ammonia nitrogen (NH 3 -N). It has been confirmed that air stripping (at pH 11.0 and aeration time 18 h) effectively removed 96.6% of the ammonia. The Fenton process was investigated under optimum conditions (pH 3.0, FeSO 4 .7H 2 O of 20 g l -1 and H 2 O 2 of 20 ml l -1 ), COD removal of up to 60.8% was achieved. Biodegradability (BOD 5 /COD ratio) increased from 0.18 to 0.38. Thereafter the Fenton effluent was mixed with sewage at dilutions to a ratio of 1:3 before it was subjected to the SBR reactor; under the optimum aeration time of 20 h, up to 82.8% BOD 5 removal and 83.1% COD removal were achieved. The optimum coagulant (Fe 2 (SO 4 ) 3 ) was a dosage of 800 mg l -1 at pH of 5.0, which reduced COD to an amount of 280 mg l -1 . These combined processes were successfully employed and very effectively decreased pollutant loading.

  9. Bio-Electron-Fenton (BEF) process driven by microbial fuel cells for triphenyltin chloride (TPTC) degradation

    Energy Technology Data Exchange (ETDEWEB)

    Yong, Xiao-Yu; Gu, Dong-Yan; Wu, Yuan-Dong [College of Biotechnology and Pharmaceutical Engineering, Nanjing TECH University, Nanjing 211816 (China); Bioenergy Research Institute, Nanjing TECH University, Nanjing 211816 (China); Yan, Zhi-Ying [Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology, Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Science, Chengdu 610041 (China); Zhou, Jun; Wu, Xia-Yuan [College of Biotechnology and Pharmaceutical Engineering, Nanjing TECH University, Nanjing 211816 (China); Bioenergy Research Institute, Nanjing TECH University, Nanjing 211816 (China); Wei, Ping [College of Biotechnology and Pharmaceutical Engineering, Nanjing TECH University, Nanjing 211816 (China); Jia, Hong-Hua [College of Biotechnology and Pharmaceutical Engineering, Nanjing TECH University, Nanjing 211816 (China); Bioenergy Research Institute, Nanjing TECH University, Nanjing 211816 (China); Zheng, Tao, E-mail: zhengtao@ms.giec.ac.cn [Guangzhou Institute of Energy Conversion, Chinese Academy of Science, Nengyuan Road, Guangzhou 510640 (China); Yong, Yang-Chun, E-mail: ycyong@ujs.edu.cn [Biofuels Institute, School of the Environment, Jiangsu University, Zhenjiang 212013 (China); Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2017-02-15

    Graphical abstract: Schematic diagram of the Bio-Electron-Fenton (BEF) process for TPTC degradation. - Highlights: • A Bio-Electro-Fenton process was performed for TPTC degradation. • TPTC removal efficiency achieved 78.32 ± 2.07% within 100 h. • The TPTC degradation rate (0.775 ± 0.021 μmol L{sup −1} h{sup −1}) was much higher than previous reports. - Abstract: The intensive use of triphenyltin chloride (TPTC) has caused serious environmental pollution. In this study, an effective method for TPTC degradation was proposed based on the Bio-Electron-Fenton process in microbial fuel cells (MFCs). The maximum voltage of the MFC with graphite felt as electrode was 278.47% higher than that of carbon cloth. The electricity generated by MFC can be used for in situ generation of H{sub 2}O{sub 2} to a maximum of 135.96 μmol L{sup −1} at the Fe@Fe{sub 2}O{sub 3(*)}/graphite felt composite cathode, which further reacted with leached Fe{sup 2+} to produce hydroxyl radicals. While 100 μmol L{sup −1} TPTC was added to the cathodic chamber, the degradation efficiency of TPTC reached 78.32 ± 2.07%, with a rate of 0.775 ± 0.021 μmol L{sup −1} h{sup −1}. This Bio-Electron-Fenton driving TPTC degradation might involve in Sn−C bonds breaking and the main process is probably a stepwise dephenylation until the formation of inorganic tin and CO{sub 2}. This study provides an energy saving and efficient approach for TPTC degradation.

  10. Bio-Electron-Fenton (BEF) process driven by microbial fuel cells for triphenyltin chloride (TPTC) degradation

    International Nuclear Information System (INIS)

    Yong, Xiao-Yu; Gu, Dong-Yan; Wu, Yuan-Dong; Yan, Zhi-Ying; Zhou, Jun; Wu, Xia-Yuan; Wei, Ping; Jia, Hong-Hua; Zheng, Tao; Yong, Yang-Chun

    2017-01-01

    Graphical abstract: Schematic diagram of the Bio-Electron-Fenton (BEF) process for TPTC degradation. - Highlights: • A Bio-Electro-Fenton process was performed for TPTC degradation. • TPTC removal efficiency achieved 78.32 ± 2.07% within 100 h. • The TPTC degradation rate (0.775 ± 0.021 μmol L"−"1 h"−"1) was much higher than previous reports. - Abstract: The intensive use of triphenyltin chloride (TPTC) has caused serious environmental pollution. In this study, an effective method for TPTC degradation was proposed based on the Bio-Electron-Fenton process in microbial fuel cells (MFCs). The maximum voltage of the MFC with graphite felt as electrode was 278.47% higher than that of carbon cloth. The electricity generated by MFC can be used for in situ generation of H_2O_2 to a maximum of 135.96 μmol L"−"1 at the Fe@Fe_2O_3_(_*_)/graphite felt composite cathode, which further reacted with leached Fe"2"+ to produce hydroxyl radicals. While 100 μmol L"−"1 TPTC was added to the cathodic chamber, the degradation efficiency of TPTC reached 78.32 ± 2.07%, with a rate of 0.775 ± 0.021 μmol L"−"1 h"−"1. This Bio-Electron-Fenton driving TPTC degradation might involve in Sn−C bonds breaking and the main process is probably a stepwise dephenylation until the formation of inorganic tin and CO_2. This study provides an energy saving and efficient approach for TPTC degradation.

  11. Application of the Fenton's process in a bubble column reactor for hydroquinone degradation.

    Science.gov (United States)

    Lima, Vanessa N; Rodrigues, Carmen S D; Madeira, Luis M

    2017-11-27

    The aim of this study was to assess the degradation and mineralization of hydroquinone (HQ) by the Fenton's process in a bubble column reactor (BCR). The effect of the main operating variables, namely, air flow rate, effluent volume, hydrogen peroxide (H 2 O 2 ) concentration, catalyst (Fe 2+ ) dose, initial pH, and temperature, were assessed. For all air flow rates tested, no concentration gradients along the column were noticed, evidencing that a good mixing was reached in the BCR. For the best conditions tested ([H 2 O 2 ] = 500 mg/L, [Fe 2+ ] = 45 mg/L, T = 24 °C, Q air  = 2.5 mL/min, pH = 3.0, and V = 5 L), complete HQ degradation was reached, with ~ 39% of total organic carbon (TOC) removal, and an efficiency of the oxidant use-η H2O2 -of 0.39 (ratio between TOC removed per H 2 O 2 consumed normalized by the theoretical stoichiometric value); moreover, a non-toxic effluent was generated. Under these conditions, the intermediates and final oxidation compounds identified and quantified were a few carboxylic acids, namely, maleic, pyruvic, and oxalic. As a strategy to improve the TOC removal, a gradual dosage of the optimal H 2 O 2 concentration was implemented, being obtained ~ 55% of mineralization (with complete HQ degradation). Finally, the matrix effect was evaluated, for which a real wastewater was spiked with 100 mg/L of HQ; no reduction in terms of HQ degradation and mineralization was observed compared to the solution in distilled water.

  12. Investigation of optimum conditions and costs estimation for degradation of phenol by solar photo-Fenton process

    Science.gov (United States)

    Gar Alalm, Mohamed; Tawfik, Ahmed; Ookawara, Shinichi

    2017-03-01

    In this study, solar photo-Fenton reaction using compound parabolic collectors reactor was assessed for removal of phenol from aqueous solution. The effect of irradiation time, initial concentration, initial pH, and dosage of Fenton reagent were investigated. H2O2 and aromatic intermediates (catechol, benzoquinone, and hydroquinone) were quantified during the reaction to study the pathways of the oxidation process. Complete degradation of phenol was achieved after 45 min of irradiation when the initial concentration was 100 mg/L. However, increasing the initial concentration up to 500 mg/L inhibited the degradation efficiency. The dosage of H2O2 and Fe+2 significantly affected the degradation efficiency of phenol. The observed optimum pH for the reaction was 3.1. Phenol degradation at different concentration was fitted to the pseudo-first order kinetic according to Langmuir-Hinshelwood model. Costs estimation for a large scale reactor based was performed. The total costs of the best economic condition with maximum degradation of phenol are 2.54 €/m3.

  13. Color, TOC and AOX removals from pulp mill effluent by advanced oxidation processes: A comparative study

    International Nuclear Information System (INIS)

    Catalkaya, Ebru Cokay; Kargi, Fikret

    2007-01-01

    Pulp mill effluent containing toxic chemicals was treated by different advanced oxidation processes (AOPs) consisting of treatments by hydrogen peroxide, Fenton's reagent (H 2 O 2 /Fe 2+ ), UV, UV/H 2 O 2 , photo-Fenton (UV/H 2 O 2 /Fe 2+ ), ozonation and peroxone (ozone/H 2 O 2 ) in laboratory-scale reactors for color, total organic carbon (TOC) and adsorbable organic halogens (AOX) removals from the pulp mill effluent. Effects of some operating parameters such as the initial pH, oxidant and catalyst concentrations on TOC, color, AOX removals were investigated. Almost every method used resulted in some degree of color removal from the pulp mill effluent. However, the Fenton's reagent utilizing H 2 O 2 /Fe 2+ resulted in the highest color, TOC and AOX removals under acidic conditions when compared with the other AOPs tested. Approximately, 88% TOC, 85% color and 89% AOX removals were obtained by the Fenton's reagent at pH 5 within 30 min. Photo-Fenton process yielded comparable TOC (85%), color (82%) and AOX (93%) removals within 5 min due to oxidations by UV light in addition to the Fenton's reagent. Fast oxidation reactions by the photo-Fenton treatment makes this approach more favorable as compared to the others used

  14. Fenton process combined with coagulation for the treatment of black liquor from bioethanol wastewater

    Science.gov (United States)

    Muryanto, Muryanto; Hanifah, Ummu; Amriani, Feni; Ibadurrahman, Ahmad Faiz; Sari, Ajeng Arum

    2017-11-01

    High amounts of black liquor are generated from bioethanol production by using oil palm empty fruit bunches. The black liquor is waste from alkaline pretreatment, it contains high amount of an alkaline solution (NaOH). The black liquor wastewater was highly contaminated with organic materials, and quite toxic for aquatic ecosystems if discharged directly into waters. This study aimed to determine ability of Fenton process combined with coagulation to treat black liquor. The addition 5% of polyaluminium chloride (PAC) could decolorized black liquor, degraded lignin, and produced sludge 70.64%, 68.28%, and 2.76 gram, respectively. Decolorization of black liquor was in line with degradation of black liquor because lignin is the main compound in black liquor. SEM images after addition of PAC of 5% indicated fragmentation of structure. Fenton reagent consist of 0.7 M FeSO4+ 3M H2O2 has able to decolorize black liquor, degrade lignin, and produce sludge 51.67% and 25.44%, and 0.44 gram, respectively. It was concluded that black liquor wastewater from bioethanol can be treated by using Fenton process combined with coagulation. However, these methods still need improvement to obtain the higher degradation rate, and coagulation sludge needs further consideration.

  15. Changes of turbidity during the phenol oxidation by photo-Fenton treatment.

    Science.gov (United States)

    Villota, Natalia; Camarero, Luis M; Lomas, Jose M; Perez, Jonatan

    2014-11-01

    Turbidity presented by phenol solutions oxidized with Fenton reagent shows the tendency of a first order intermediate kinetics. Thus, turbidity can be considered a representative parameter of the presence of intermediate oxidation species, which are generated along the decomposition of toxic and reluctant contaminants, such as phenol. Moreover, that parameter presents a linear dependence with the catalyst dosage, but is also determined by the initial contaminant load. When analyzing the oxidation mechanism of phenol, it is found that the maximum turbidity occurs when the treatment is carried out at oxidant to phenol molar ratios R = 4.0. These oxidation conditions correspond to the presence of a reaction mixture mainly composed of dihydroxylated rings, precursors of the muconic acid formation. The oxidation via "para" comprises the formation reactions of charge transfer complexes (quinhydrone), between the para-dihydroxylated intermediates (hydroquinone) and the para-substituted quinones (p-benzoquinone), which are quite unstable and reactive species, quickly decomposed into hydroxyhydroquinones. Working with oxidant ratios up to R = 6.0, the maximum observed value of turbidity in the oxidized solutions is kept almost constant. It is found that, in these conditions, the pyrogallol formation is maximal, what is generated through the degradation of ortho-species (catechol and ortho-benzoquinone) and meta-substituted (resorcinol). Operating with ratios over R = 6.0, these intermediates are decomposed into biodegradable acids, generating lower turbidity in the solution. Then, the residual turbidity is a function of the molar ratio of the ferrous ions vs. moles of oxidant utilized in the essays, that lets to estimate the stoichiometric dosage of catalyst as 20 mg/L at pH = 3.0, whereas operating in stoichiometric conditions, R = 14.0, the residual turbidity of water results almost null.

  16. Enhanced bioremediation of oil contaminated soil by graded modified Fenton oxidation.

    Science.gov (United States)

    Xu, Jinlan; Xin, Lei; Huang, Tinglin; Chang, Kun

    2011-01-01

    Graded modified Fenton's (MF) oxidation is a strategy in which H2O2 is added intermittently to prevent a sharp temperature increase and undesired soil sterilization at soil circumneutral pH versus adding the same amount of H2O2 continuously. The primary objective of the present study was to investigate whether a mild MF pre-oxidation such as a stepwise addition of H2O2 can prevent sterilization and achieve a maximum degradation of tank oil in soil. Optimization experiments of graded MF oxidation were conducted using citric acid, oxalic acid and SOLV-X as iron chelators under different frequencies of H2O2 addition. The results indicated that the activity order of iron chelates decreased as: citric acid (51%) > SOLV-X (44%) > oxalic acid (9%), and citric acid was found to be an optimized iron chelating agent of graded MF oxidation. Three-time addition of H2O2 was found to be favorable and economical due to decreasing total petroleum hydrocarbon removal from three time addition (51%) to five time addition (59%). Biological experiments were conducted after graded MF oxidation of tank oil completed under optimum conditions mentioned above. After graded oxidation, substantially higher increase (31%) in microbial activity was observed with excessive H2O2 (1470 mmol/L, the mol ratio of H2O2:Fe2+ was 210:1) than that of non-oxidized soil. Removal efficiency of tank oil was up to 93% after four weeks. Especially, the oil fraction (C10-C40) became more biodagradable after graded MF oxidation than its absence. Therefore, graded MF oxidation is a mild pretreatment to achieve an effective bioremediation of oil contaminated soil.

  17. How does intensification influence the operational and environmental performance of photo-Fenton processes at acidic and circumneutral pH.

    Science.gov (United States)

    Salazar, Luis Miguel; Grisales, Claudia Mildred; Garcia, Dorian Prato

    2018-05-31

    This study evaluates the technical, economical, and environmental impact of sodium persulfate (Na 2 S 2 O 8 ) as an enhancing agent in a photo-Fenton process within a solar-pond type reactor (SPR). Photo-Fenton (PF) and photo-Fenton intensified with the addition of persulfate (PFPS) processes decolorize 97% the azo dye direct blue 71 (DB71) and allow producing a highly biodegradable effluent. Intensification with persulfate allowed reducing treatment time in 33% (from 120 to 80 min) and the consumption of chemical auxiliaries needed for pH adjustment. Energy, reagents, and chemical auxiliaries are still and environmental hotspot for PF and PFPS; however, it is worth mentioning that their environmental footprint is lower than that observed for compound parabolic concentrator (CPC)-type reactors. A life-cycle assessment (LCA) confirms that H 2 O 2 , NaOH, and energy consumption are the variables with the highest impact from an environmental standpoint. The use of persulfate reduced the relative impact in 1.2 to 12% in 12 of the 18 environmental categories studied using the ReCiPe method. The PFPS process emits 1.23 kg CO 2 (CO 2 -Eqv/m 3 treated water). On the other hand, the PF process emits 1.28 kg CO 2 (CO 2 -Eqv/m 3 treated water). Process intensification, chemometric techniques, and the use of SPRs minimize the impact of some barriers (reagent and energy consumption, technical complexity of reactors, pressure drops, dirt on the reflecting surfaces, fragility of reactor materials), limiting the application of advanced oxidation systems at an industrial level, and decrease treatment cost as well as potential environmental impacts associated with energy and reagents consumption. Treatment costs for PF processes (US$0.78/m 3 ) and PFPS processes (US$0.63/m 3 ) were 20 times lower than those reported for photo-Fenton processes in CPC-type reactors.

  18. Treatment of Effluent from a Factory of Paints Using Solar Photo-Fenton Process

    Directory of Open Access Journals (Sweden)

    Alam Gustavo Trovó

    2013-01-01

    Full Text Available We evaluated the use of Fenton reactions induced by solar radiation in the treatment of effluent from a factory of paints for buildings, after prior removal of the suspended solids. The increase of H2O2 concentration from 100 to 2500 mg L−1 for a [Fe2+] = 105 mg L−1 contributed to the reduction of DOC, COD, and toxicity. Our best results were achieved using 1600 mg L−1 H2O2, with 90% of DOC and COD removal and a complete removal of the toxicity with respect to Artemia salina. Additionally, through increasing Fe2+ concentration from 15 to 45 mg L−1, the DOC removal rate increased 11 times, remaining almost constant in the range above 45 until 105 mg L−1. Under our best experimental conditions, 80% of DOC removal was achieved after an accumulated dose of 130 kJ m−2 of UVA radiation (82±17 min of solar irradiation under an average UVA irradiance of 34.1±7.3 W m−2, while 40% of DOC removal was reached after 150 min under only thermal Fenton reactions. The results suggest the effectiveness of implementation of solar photo-Fenton process in the decontamination and detoxification of effluents from factories of paints for buildings.

  19. Practical applications of the Fenton reaction to the removal of chlorinated aromatic pollutants. Oxidative degradation of 2,4-dichlorophenol.

    Science.gov (United States)

    Detomaso, Antonia; Lopez, Antonio; Lovecchio, Giangiuseppe; Mascolo, Giuseppe; Curci, Ruggero

    2003-01-01

    Chlorophenols (CPs) constitute a group of organic pollutants that are introduced into the environment as a result of several man-made activities, such as uncontrolled use of pesticides and herbicides, and as byproducts in the paper pulp bleaching. Promising removal technologies of chlorinated aromatics consist in the application of advanced oxidation processes (AOPs) that can provide an almost total degradation of a variety of contaminants. Among these, wide application find Fenton systems based on generation of reactive species having a high oxidizing power, such as hydroxyl radical HO*. Our objective was that of determining the overall degradation efficiency of the model compound 2,4-dichlorophenol (DCP) by thermal Fenton-type oxidation systems with a view toward defining in more details relevant process parameters, the effect of reaction temperature and of co-catalyst Cu2+. Reaction conditions were similar to those generally adopted as optimal in many practical applications, i.e. pollutant/Fe2+ (as FeSO4) ratio ca. 20, Fe2+/Cu2+ (co-catalyst) 2:1, pH adjusted and controlled at pH 3, and H2O2 in excess (up to four-fold over the stoichiometric amount required for complete mineralization). The results demonstrate that it is advantageous to carry out the reaction at a temperature markedly higher (70 degrees C) than ambient. The stepwise addition of H2O2 in aliquots yields an efficient transformation, while allowing a convenient control of the reaction exothermicity. Under these conditions, the essentially complete removal of the initial DCP is accomplished using just one equiv of H2O2 during 15 min; excess H2O2 (5 equivalents) yields extensive substrate mineralization. Also relevant, at 70 degrees C dechlorination of the initial DCP (and of derived reaction intermediates) is remarkably extensive (3-5% residual TOX), already with the addition of 1 equiv of H2O2. At the end of the reaction, IC and IC-MS analyses of the solution reveal that only low-molecular weight

  20. Cosmetic wastewater treatment by coagulation and advanced oxidation processes.

    Science.gov (United States)

    Naumczyk, Jeremi; Bogacki, Jan; Marcinowski, Piotr; Kowalik, Paweł

    2014-01-01

    In this study, the treatment process of three cosmetic wastewater types has been investigated. Coagulation allowed to achieve chemical oxygen demand (COD) removal of 74.6%, 37.7% and 74.0% for samples A (Al2(SO4)3), B (Brentafloc F3) and C (PAX 16), respectively. The Fenton process proved to be effective as well - COD removal was equal to 75.1%, 44.7% and 68.1%, respectively. Coagulation with FeCl3 and the subsequent photo-Fenton process resulted in the best values of final COD removal equal to 92.4%, 62.8% and 90.2%. In case of the Fenton process, after coagulation these values were equal to 74.9%, 50.1% and 84.8%, while in case of the H2O2/UV process, the obtained COD removal was 83.8%, 36.2% and 80.9%. High value of COD removal in the Fenton process carried out for A and C wastewater samples was caused by a significant contribution of the final neutralization/coagulation. Very small effect of the oxidation reaction in the Fenton process in case of sample A resulting from the presence of antioxidants, 'OH radical scavengers' in the wastewater.

  1. Photo-Fenton oxidation of 3-amino-5-methylisoxazole: a by-product from biological breakdown of some pharmaceutical compounds.

    Science.gov (United States)

    Souza, Bianca M; Marinho, Belisa A; Moreira, Francisca C; Dezotti, Márcia W C; Boaventura, Rui A R; Vilar, Vítor J P

    2017-03-01

    The present study aims to assess the removal of 3-amino-5-methylisoxazole (AMI), a recalcitrant by-product resulting from the biological breakdown of some pharmaceuticals, applying a solar photo-Fenton process assisted by ferrioxalate complexes (SPFF) (Fe 3+ /H 2 O 2 /oxalic acid/UVA-Vis) and classical solar photo-Fenton process (SPF) (Fe 2+ /H 2 O 2 /UVA-Vis). The oxidation ability of SPFF was evaluated at different iron/oxalate molar ratios (1:3, 1:6, and 1:9, with [total iron] = 3.58 × 10 -2  mM and [oxalic acid] = 1.07 × 10 -1 , 2.14 × 10 -1 and 3.22 × 10 -1  mM, respectively) and pH values (3.5-6.5), using low iron contents (2.0 mg Fe 3+ L -1 ). Additionally, the use of other organic ligands such as citrate and ethylenediamine-N,N'-disuccinic acid (EDDS) was tested. The oxidation power of the classical SPF was assessed at different pH values (2.8-4.0) using 2.0 mg Fe 2+ per liter. Furthermore, the effect of AMI concentration (2-20 mg L -1 ), presence of inorganic ions (Cl - , SO 4 2- , NO 3 - , HCO 3 - , NH 4 + ), and radical scavengers (sodium azide and D-mannitol) on the SPF method at pH 3.5 was also assessed. Experiments were done using a lab-scale photoreactor with a compound parabolic collector (CPC) under simulated solar radiation. A pilot-scale assay was conducted using the best operation conditions. While at near neutral pH, an iron/oxalate molar ratio of 1:9 led to the removal of 72 % of AMI after 90 min of SPFF, at pH 3.5, an iron/oxalate molar ratio of 1:3 was enough to achieve complete AMI degradation (below the detection limit) after 30 min of reaction. The SPF process at pH 3.5 underwent a slower AMI degradation, reaching total AMI degradation after 40 min of reaction. The scale up of SPF process showed a good reproducibility. Oxalic and oxamic acids were identified as the main low-molecular-weight carboxylic acids detected during the pilot-scale SPF reaction. Graphical abstract ᅟ.

  2. Solar photo-Fenton process on the abatement of antibiotics at a pilot scale: Degradation kinetics, ecotoxicity and phytotoxicity assessment and removal of antibiotic resistant enterococci.

    Science.gov (United States)

    Michael, I; Hapeshi, E; Michael, C; Varela, A R; Kyriakou, S; Manaia, C M; Fatta-Kassinos, D

    2012-11-01

    This work investigated the application of a solar driven advanced oxidation process (solar photo-Fenton), for the degradation of antibiotics at low concentration level (μg L(-1)) in secondary treated domestic effluents at a pilot-scale. The examined antibiotics were ofloxacin (OFX) and trimethoprim (TMP). A compound parabolic collector (CPC) pilot plant was used for the photocatalytic experiments. The process was mainly evaluated by a fast and reliable analytical method based on a UPLC-MS/MS system. Solar photo-Fenton process using low iron and hydrogen peroxide doses ([Fe(2+)](0) = 5 mg L(-1); [H(2)O(2)](0) = 75 mg L(-1)) was proved to be an efficient method for the elimination of these compounds with relatively high degradation rates. The photocatalytic degradation of OFX and TMP with the solar photo-Fenton process followed apparent first-order kinetics. A modification of the first-order kinetic expression was proposed and has been successfully used to explain the degradation kinetics of the compounds during the solar photo-Fenton treatment. The results demonstrated the capacity of the applied advanced process to reduce the initial wastewater toxicity against the examined plant species (Sorghum saccharatum, Lepidium sativum, Sinapis alba) and the water flea Daphnia magna. The phytotoxicity of the treated samples, expressed as root growth inhibition, was higher compared to that observed on the inhibition of seed germination. Enterococci, including those resistant to OFX and TMP, were completely eliminated at the end of the treatment. The total cost of the full scale unit for the treatment of 150 m(3) day(-1) of secondary wastewater effluent was found to be 0.85 € m(-3). Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Rapid and facile preparation of zinc ferrite (ZnFe{sub 2}O{sub 4}) oxide by microwave-solvothermal technique and its catalytic activity in heterogeneous photo-Fenton reaction

    Energy Technology Data Exchange (ETDEWEB)

    Anchieta, Chayene G.; Severo, Eric C.; Rigo, Caroline; Mazutti, Marcio A. [Department of Chemical Engineering, Federal University of Santa Maria, 97105-900, Santa Maria (Brazil); Kuhn, Raquel C., E-mail: raquelckuhn@yahoo.com.br [Department of Chemical Engineering, Federal University of Santa Maria, 97105-900, Santa Maria (Brazil); Muller, Edson I.; Flores, Erico M.M. [Department of Chemistry, Federal University of Santa Maria, 97105-900, Santa Maria (Brazil); Moreira, Regina F.P.M. [Department of Chemical Engineering and Food Engineering, Federal University of Santa Catarina, 88040-970, Florianópolis (Brazil); Foletto, Edson L. [Department of Chemical Engineering, Federal University of Santa Maria, 97105-900, Santa Maria (Brazil)

    2015-06-15

    In this work zinc ferrite (ZnFe{sub 2}O{sub 4}) oxide was rapidly and easily prepared by microwave-solvothermal route and its catalytic property in photo-Fenton reaction was evaluated. The effects of microwave heating time and power on the properties of produced particles were investigated. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM) and nitrogen adsorption–desorption isotherms were the techniques used for characterizing the solid products. The synthesized material was tested as a catalyst in the degradation of the textile dye molecule by the heterogeneous photo-Fenton process. Characterization results showed that the microwave heating time and power have significant influences on the formation of the phase spinel as well as on its physical properties. The reaction results showed that the ZnFe{sub 2}O{sub 4} oxide has good photocatalytic activity, which can be attributed to high surface area and pore volume, and large pore size. The ZnFe{sub 2}O{sub 4} oxide produced by the microwave irradiation exhibited promising photocatalytic activity for the removal of textile dye, reaching nearly 100% of decolorization at 40 min and 60% of mineralization at 240 min. Therefore, ZnFe{sub 2}O{sub 4} particles rapidly prepared by the microwave route have the potential for use in treatment of textile wastewater by the heterogeneous photo-Fenton process. - Highlights: • ZnFe{sub 2}O{sub 4} was synthesized by microwave-solvothermal method. • ZnFe{sub 2}O{sub 4} was prepared by different microwave heating times and powers. • ZnFe{sub 2}O{sub 4} was used as heterogeneous photo-Fenton catalyst. • Degradation of Procion red dye using heterogeneous photo-Fenton process. • ZnFe{sub 2}O{sub 4} was highly efficient to degrade textile dye under visible light.

  4. Reduction of clarithromycin and sulfamethoxazole-resistant Enterococcus by pilot-scale solar-driven Fenton oxidation.

    Science.gov (United States)

    Karaolia, Popi; Michael, Irene; García-Fernández, Irene; Agüera, Ana; Malato, Sixto; Fernández-Ibáñez, Pilar; Fatta-Kassinos, Despo

    2014-01-15

    The presence of pathogenic antibiotic-resistant bacteria in aquatic environments has become a health threat in the last few years. Their presence has increased due to the presence of antibiotics in wastewater effluents, which are not efficiently removed by conventional wastewater treatments. As a result there is a need to study the possible ways of removal of the mixtures of antibiotics present in wastewater effluents and the antibiotic-resistant bacteria, which may also spread the antibiotic resistance genes to other bacterial populations. In this study the degradation of a mixture of antibiotics i.e. sulfamethoxazole and clarithromycin, the disinfection of total enterococci and the removal of those resistant to: a) sulfamethoxazole, b) clarithromycin and c) to both antibiotics have been examined, along with the toxicity of the whole effluent mixture after treatment to the luminescent aquatic bacterium Vibrio fischeri. Solar Fenton treatment (natural solar driven oxidation) using Fenton reagent doses of 50 mg L(-1) of hydrogen peroxide and 5 mg L(-1) of Fe(3+) in a pilot-scale compound parabolic collector plant was used to examine the disinfection and antibiotic resistance removal efficiency in different aqueous matrices, namely distilled water, simulated and real wastewater effluents. There was a faster complete removal of enterococci and of antibiotics in all aqueous matrices by applying solar Fenton when compared to photolytic treatment of the matrices. Sulfamethoxazole was more efficiently degraded than clarithromycin in all three aqueous matrices (95% removal of sulfamethoxazole and 70% removal of clarithromycin in real wastewater). The antibiotic resistance of enterococci towards both antibiotics exhibited a 5-log reduction with solar Fenton in real wastewater effluent. Also after solar Fenton treatment, there were 10 times more antibiotic-resistant enterococci in the presence of sulfamethoxazole than in the presence of clarithromycin. Finally, the toxicity

  5. A review on the degradation of organic pollutants in waters by UV photoelectro-Fenton and solar photoelectro-Fenton

    OpenAIRE

    Brillas, Enric

    2014-01-01

    This paper presents a review on emerging electrochemical advanced oxidation processes (EAOPs) such as UV photoelectro-Fenton (PEF) and solar photoelectro-Fenton (SPEF) in which the irradiation of the effluent with UV light and sunlight, respectively, causes a synergistic effect on the degradation process of organic pollutants by the formation of more •OH and/or the photolysis of complexes of Fe(III) with generated carboxylic acids. Fundamentals of these EAOPs are explained to clarify their pe...

  6. Iron oxides and their applications in catalytic processes: a review

    OpenAIRE

    Oliveira, Luiz C. A.; Fabris, José D.; Pereira, Márcio C.

    2013-01-01

    A review of most of the reported studies on the use of iron oxides as catalyst in specific processes, namely Haber-Bosch reaction, Fischer-Tropsch synthesis, Fenton oxidation and photolytic molecular splitting of water to produce gaseous hydrogen, was carried out. An essential overview is thus presented, intending to address the fundamental meaning, as well as the corresponding chemical mechanisms, and perspectives on new technological potentialities of natural and synthetic iron oxides, more...

  7. Treatment of landfill leachate using a combined stripping, Fenton, SBR, and coagulation process

    Energy Technology Data Exchange (ETDEWEB)

    Guo Jinsong, E-mail: guo0768@cqu.edu.cn [Faculty of Urban Construction and Environmental Engineering, Key Laboratory of the Three Gorges Reservoir Region' s Eco-Environment, Chongqing University, Chongqing 400045 (China); Abbas, Abdulhussain A. [Faculty of Urban Construction and Environmental Engineering, Key Laboratory of the Three Gorges Reservoir Region' s Eco-Environment, Chongqing University, Chongqing 400045 (China); Faculty of Engineering, Basrah University, Basrah (Iraq); Chen Youpeng; Liu Zhiping; Fang Fang; Chen Peng [Faculty of Urban Construction and Environmental Engineering, Key Laboratory of the Three Gorges Reservoir Region' s Eco-Environment, Chongqing University, Chongqing 400045 (China)

    2010-06-15

    The leachate from Changshengqiao landfill (Chongqing, China) was characterized and submitted to a combined process of air stripping, Fenton, sequencing batch reactor (SBR), and coagulation. Optimum operating conditions for each process were identified. The performance of the treatment was assessed by monitoring the removal of organic matter (COD and BOD{sub 5}) and ammonia nitrogen (NH{sub 3}-N). It has been confirmed that air stripping (at pH 11.0 and aeration time 18 h) effectively removed 96.6% of the ammonia. The Fenton process was investigated under optimum conditions (pH 3.0, FeSO{sub 4}.7H{sub 2}O of 20 g l{sup -1} and H{sub 2}O{sub 2} of 20 ml l{sup -1}), COD removal of up to 60.8% was achieved. Biodegradability (BOD{sub 5}/COD ratio) increased from 0.18 to 0.38. Thereafter the Fenton effluent was mixed with sewage at dilutions to a ratio of 1:3 before it was subjected to the SBR reactor; under the optimum aeration time of 20 h, up to 82.8% BOD{sub 5} removal and 83.1% COD removal were achieved. The optimum coagulant (Fe{sub 2}(SO{sub 4}){sub 3}) was a dosage of 800 mg l{sup -1} at pH of 5.0, which reduced COD to an amount of 280 mg l{sup -1}. These combined processes were successfully employed and very effectively decreased pollutant loading.

  8. In-situ treatment of PCP contaminated soil by electrokinetics-Fenton-biodegradation process

    Energy Technology Data Exchange (ETDEWEB)

    Yang, G.C.C.; Chen Jenteh [Inst. of Environmental Engineering, National Sun Yat-Sen Univ., Kaohsiung (Taiwan)

    2001-07-01

    This laboratory investigation was conducted to evaluate the treatment efficiency of a process combining electrokinetic remediation (EK), Fenton process, and biodegradation for treating a pentachlorophenol (PCP) contaminated soil. For EK-Fenton experiments, the results have indicated that an increase of treatment time (e.g., from 10 to 15 days) would substantially increase the overall treatment (i.e., removal and destruction) efficiency of PCP. Only a limited increase of the treatment efficiency would be found if the concentration of FeSO{sub 4} was increased from 0.0196M to 0.098M. When scrap iron power was employed as the catalyst, the residual PCP concentration for soil near the anode end was found to be lower than that of 0.0196M FeSO{sub 4}. But its overall treatment efficiency was only 56.58%, which is lower than 68.34% obtained by using 0.0196M FeSO{sub 4} and 0.35% H{sub 2}O{sub 2}. When H{sub 2}O{sub 2} concentration was further increased to 3.5%, an overall treatment efficiency of 79.77% would be obtained when 0.0196M FeSO{sub 4} was used. When treated by EK-biodegradation process with phenol enrichment bacteria, the overall treatment efficiency of PCP was as low as 25.67%. If PCP contaminated soil was pre-treated by EK-Fenton process and followed by EK-biodegradation, an overall treatment efficiency of 100% was found to be achievable. (orig.)

  9. Impacts of operating parameters on oxidation–reduction potential and pretreatment efficacy in the pretreatment of printing and dyeing wastewater by Fenton process

    International Nuclear Information System (INIS)

    Wu, Huifang; Wang, Shihe

    2012-01-01

    Highlights: ► A real printing and dyeing wastewater was pretreated by Fenton process. ► We investigated impacts of operating parameters on ORP and pretreatment efficacy. ► Relationship among ORP, operating parameters and treatment efficacy was established. ► Pretreatment efficacy was in proportion to the exponent of temperature reciprocal. ► We investigated kinetics of color and COD removal and BOD 5 /COD ratio in solution. - Abstract: An experiment was conducted in a batch reactor for a real printing and dyeing wastewater pretreatment using Fenton process in this study. The results showed that original pH, hydrogen peroxide concentration and ferrous sulfate concentration affected ORP value and pretreatment efficacy greatly. Under experimental conditions, the optimal original pH was 6.61, and the optimal hydrogen peroxide and ferrous sulfate concentrations were 1.50 and 0.75 g L −1 , respectively. The relationship among ORP, original pH, hydrogen peroxide concentration, ferrous sulfate concentration, and color (COD or BOD 5 /COD) was established, which would be instructive in on-line monitoring and control of Fenton process using ORP. In addition, the effects of wastewater temperature and oxidation time on pretreatment efficacy were also investigated. With an increase of temperature, color and COD removal efficiencies and BOD 5 /COD ratio increased, and they were in proportion to the exponent of temperature reciprocal. Similarly, color and COD removal efficiencies increased with increasing oxidation time, and both color and COD removal obeyed the first-order kinetics. The BOD 5 /COD ratio could be expressed by a second-degree polynomial with respect to oxidation time, and the best biodegradability of wastewater was present at the oxidation time of 6.10 h.

  10. Fenton-like oxidation of 2,4-DCP in aqueous solution using iron-based nanoparticles as the heterogeneous catalyst.

    Science.gov (United States)

    Li, Renchao; Gao, Ying; Jin, Xiaoying; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

    2015-01-15

    In this report, various iron-based nanoparticles (nZVI, n-Ni/Fe, n-Pd/Fe) were used for both heterogeneous Fenton oxidation of 2,4-dichlorophenol (2,4-DCP) and reductive dechlorination of 2,4-DCP in order to understand their roles in the Fenton oxidation and the reductive degradation of 2,4-DCP. The dechlorination efficiency of 2,4-DCP using nZVI, n-Ni/Fe, n-Fe/Pd and Fe(2)(+) was 6.48%, 6.80%, 15.95%, 5.02%, while Fenton oxidation efficiency of 2,4-DCP was 57.87%, 34.23%, 27.94%, 19.61% after 180 min, respectively. The new findings included a higher dechlorination using n-Fe/Pd due to Pd effective catalysis and the effective heterogeneous Fenton oxidation using nZVI depending on reductive dechlorination and heterogeneous Fenton oxidation occurs simultaneously. However, nZVI as the potential catalyst for heterogeneous Fenton was observed, and SEM, EDS and XRD demonstrate that change on the nZVI surface occurred due to the Fe(2+) leaching, and Total Organic Carbon (TOC) (30.71%) shows that 2,4-DCP was degraded. Furthermore, the experiment indicates that the pH values and concentration of 2,4-DCP significantly impacted on the heterogeneous Fenton oxidation of 2,4-DCP and the data fits well with the pseudo first-order kinetic model, which was a diffusion-controlled reaction. Finally, a possible mechanism for degradation of 2,4-DCP was proposed. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Mn(II) oxidation in Fenton and Fenton type systems : Identification of Reaction Efficiency and Reaction Products

    NARCIS (Netherlands)

    van Genuchten, C.M.; Peña, Jasquelin

    2017-01-01

    Efficient and low-cost methods of removing aqueous Mn(II) are required to improve the quality of impacted groundwater supplies. In this work, we show that Fe(0) electrocoagulation (EC) permits the oxidative removal of Mn(II) from solution by reaction with the reactive oxidant species produced

  12. Synergistic efficiency of the desilication of brackish underground water in Saudi Arabia by coupling γ-radiation and Fenton process: Membrane scaling prevention in reverse osmosis process

    Science.gov (United States)

    Aljohani, Mohammed S.

    2017-12-01

    One of the main water resources in arid Saudi Arabia is underground water. However, this brackish water has high silica content which can cause a recalcitrant deposit on the membrane in the reverse osmosis units during its desalination. In this study, we examined the synergistic efficiency of the removal of silica from the Buwaib water sample, when combining two advanced oxidation processes, γ-irradiation and the Fenton process, using hydrogen peroxide and zero valent metal iron as source of Fe3+. This latter adsorbs effectively on silica and co-precipitate. The influence of absorbed dose, iron dosage and pH effect were investigated. This preliminary study showed that these attractive and effective hybrid processes are very efficient in removing silica.

  13. Concomitant degradation of bisphenol A during ultrasonication and Fenton oxidation and production of biofertilizer from wastewater sludge.

    Science.gov (United States)

    Mohapatra, D P; Brar, S K; Tyagi, R D; Surampalli, R Y

    2011-09-01

    Degradation of bisphenol A (BPA), an endocrine disruptor, from wastewater sludge (WWS) has attracted great interest recently. In the present study, the effects of different pre-treatment methods, including ultrasonication (US), Fenton's oxidation (FO) and ferro-sonication (FS) was assessed in terms of increase in solubilization of WWS and simultaneous degradation of BPA. Among US, FO and FS pre-treatment, higher suspended solids (SS), volatile suspended solids (VSS), chemical oxygen demand (COD) and soluble organic carbon (SOC) solubilization (39.7%, 51.2%, 64.5% and 17.6%, respectively) was observed during a ferro-sonication pre-treatment process carried out for 180 min, resulting in higher degradation of BPA (82.7%). In addition, the effect of rheological parameters (viscosity and particle size) and zeta potential on the degradation of BPA in raw and different pre-treated sludges were also investigated. The results showed that a decrease in viscosity and particle size and an increase in zeta potential resulted in higher degradation of BPA. BPA degradation by laccases produced by Sinorhizobium meliloti in raw and pre-treated sludge was also determined. Higher activity of laccases (207.9 U L(-1)) was observed in ferro-sonicated pre-treated sludge (180 min ultrasonic time), resulting in higher removal of BPA (0.083 μg g(-1)), suggesting concomitant biological degradation of BPA. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Photocatalytic degradation and photo-Fenton oxidation of Congo red dye pollutants in water using natural chromite—response surface optimization

    Science.gov (United States)

    Shaban, Mohamed; Abukhadra, Mostafa R.; Ibrahim, Suzan S.; Shahien, Mohamed. G.

    2017-12-01

    Refined natural Fe-chromite was characterized by XRD, FT-IR, reflected polarized microscope, XRF and UV spectrophotometer. Photocatalytic degradation and photo-Fenton oxidation of Congo red dye by Fe-chromite was investigated using 1 mL H2O2. The degradation of dye was studied as a function of illumination time, chromite mass, initial dye concentration, and pH. Fe-chromite acts as binary oxide system from chromium oxide and ferrous oxide. Thus, it exhibits photocatalytic properties under UV illumination and photo-Fenton oxidation after addition of H2O2. The degradation in the presence of H2O2 reached the equilibrium stage after 8 h (59.4%) but in the absence of H2O2 continued to 12 h (54.6%). Photocatalytic degradation results fitted well with zero, first order and second order kinetic model but it represented by second order rather than by the other models. While the photo-Fenton oxidation show medium fitting with the second order kinetic model only. The values of kinetic rate constants for the photo-Fenton oxidation were greater than those for the photocatalytic degradation. Thus, degradation of Congo red dye using chromite as catalyst is more efficient by photo-Fenton oxidation. Based on the response surface analysis, the predicted optimal conditions for maximum removal of Congo red dye by photocatalytic degradation (100%) were 12 mg/l, 0.14 g, 3, and 11 h for dye concentration, chromite mass, pH, and illumination time, respectively. Moreover, the optimum condition for photo-Fenton oxidation of dye (100%) is 13.5 mg/l, 0.10 g, 4, and 10 h, respectively.

  15. Mineralization of phthalic acid by solar photoelectro-Fenton with a stirred boron-doped diamond/air-diffusion tank reactor: Influence of Fe3+ and Cu2+ catalysts and identification of oxidation products

    International Nuclear Information System (INIS)

    Garcia-Segura, Sergi; Salazar, Ricardo; Brillas, Enric

    2013-01-01

    Highlights: • Almost total mineralization of phthalic acid by solar photoelectro-Fenton with Fe 3+ , Cu 2+ and Fe 3+ –Cu 2+ mixtures. • Hydroxyl radical generation from photo-Fenton reaction under solar radiation. • Enhancement of the mineralization rate using Fe 3+ and small amounts of Cu 2+ . • Detection of eleven aromatic intermediates and six short-linear carboxylic acids. • Oxidation of Cu(II)-carboxylate complexes with ·OH and photolysis of Fe(III)-carboxylate species. -- Abstract: Here, the substrate decay and mineralization rate for 100 cm 3 of a 2.0 mM phthalic acid solution in 0.10 M Na 2 SO 4 of pH 3.0 have been studied by electro-Fenton (EF) and solar photoelectro-Fenton (SPEF). The electrochemical cell was a stirred tank reactor containing a 3 cm 2 boron-doped diamond (BDD) anode and a 3 cm 2 air-diffusion cathode that generates H 2 O 2 . Cu 2+ and/or Fe 3+ were added as catalysts with total concentration of 0.50 mM and a constant current density of 33.3 mA cm −2 was applied. In EF with Cu 2+ or Fe 3+ alone and SPEF with only Cu 2+ , phthalic acid decayed slowly and poor mineralization was reached because the main oxidant was ·OH produced at the BDD surface from water oxidation. In contrast, the substrate destruction was largely enhanced using SPEF with 0.50 mM Fe 3+ since a high quantity of oxidant ·OH was produced in the bulk induced by photo-Fenton reaction. This treatment led to an almost total mineralization by the photolysis of generated Fe(III)-carboxylate complexes. In all cases, the decay of phthalic acid obeyed a pseudo-first-order reaction. The combination of Cu 2+ and Fe 3+ as catalysts accelerated the mineralization process in SPEF because Cu(II)-carboxylate complexes were also removed with ·OH formed from photo-Fenton reaction. The best SPEF process was found for 0.125 mM Cu 2+ + 0.375 mM Fe 3+ , giving rise to 99% mineralization with 40% current efficiency and 0.294 kWh g −1 TOC energy consumption. Eleven aromatics

  16. Oxidation of organic compounds in wastewater from the humid processing of coffee berries

    International Nuclear Information System (INIS)

    Goncalves, Maraisa; Guerreiro, Mario Cesar; Oliveira, Luiz Carlos Alves; Rocha, Cristian Luciana da

    2008-01-01

    Materials based on pure iron oxide and impregnated with niobia (Nb 2 O 5 ) were prepared. Their catalytic activities were tested on the oxidation of compounds present in the wastewater from the processing of coffee berries. Particularly caffeine and catechol were tested. The oxidation reactions were carried out with the following systems: UV/H 2 O 2 ; photo-Fenton and heterogeneous Fenton. All materials were characterized with X-ray diffraction, Moessbauer and infrared spectroscopy. Iron was mainly in the forms of goethite and maghemite. The oxidation kinetics were monitored by UV-vis and the oxidation products were monitored by mass spectrometry. The photo-Fenton reaction presented highest oxidation efficiency, removing 98% of all caffeine and catechol contents. (author)

  17. Assessment of Fenton's reagent and ozonation as pre-treatments for increasing the biodegradability of aqueous diethanolamine solutions from an oil refinery gas sweetening process.

    Science.gov (United States)

    Durán-Moreno, A; García-González, S A; Gutiérrez-Lara, M R; Rigas, F; Ramírez-Zamora, R M

    2011-02-28

    The aim of this work was to evaluate the efficiency of three chemical oxidation processes for increasing the biodegradability of aqueous diethanolamine solutions (aqueous DEA solutions), to be used as pre-treatments before a biological process. The raw aqueous DEA solution, sourced from a sour gas sweetening plant at a Mexican oil refinery, was first characterized by standardized physico-chemical methods. Then experiments were conducted on diluted aqueous DEA solutions to test the effects of Fenton's reagent, ozone and ozone-hydrogen peroxide on the removal of some physicochemical parameters of these solutions. Lastly, biodegradability tests based on Dissolved Organic Carbon Die Away OECD301-A, were carried out on a dilution of the raw aqueous DEA solution and on the treated aqueous DEA solutions, produced by applying the best experimental conditions determined during the aforementioned oxidation tests. Experimental results showed that for aqueous DEA solutions treated with Fenton's reagent, the best degradation rate (70%) was obtained at pH 2.8, with Fe(2+) and H(2)O(2) at doses of 1000 and 10,000 mg/L respectively. In the ozone process, the best degradation (60%) was observed in aqueous DEA solution (100 mg COD/L), using 100 mg O(3)/L at pH 5. In the ozone-hydrogen peroxide process, no COD or DOC removals were observed. The diluted spent diethanolamine solution showed its greatest increase in biodegradability after a reaction period of 28 days when treated with Fenton's reagent, but after only 15 days in the case of ozonation. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Treatment of reverse osmosis (RO) concentrate by the combined Fe/Cu/air and Fenton process (1stFe/Cu/air-Fenton-2ndFe/Cu/air).

    Science.gov (United States)

    Ren, Yi; Yuan, Yue; Lai, Bo; Zhou, Yuexi; Wang, Juling

    2016-01-25

    To decompose or transform the toxic and refractory reverse osmosis (RO) concentrate and improve the biodegradability, 1stFe/Cu/air-Fenton-2ndFe/Cu/air were developed to treat RO concentrate obtained from an amino acid production plant in northern China. First, their operating conditions were optimized thoroughly. Furthermore, 5 control experiments were setup to confirm the superiority of 1stFe/Cu/air-Fenton-2ndFe/Cu/air and synergistic reaction between Fe/Cu/air and Fenton. The results suggest that the developed method could obtain high COD removal (65.1%) and BOD5/COD ratio (0.26) due to the synergistic reaction between Fe/Cu/air and Fenton. Under the optimal conditions, the influent and effluent of 1stFe/Cu/air-Fenton-2ndFe/Cu/air and 5 control experiments were analyzed by using UV, FTIR, EEM and LC, which confirm the superiority of 1stFe/Cu/air-Fenton-2ndFe/Cu/air. Therefore, the developed method in this study is a promising process for treatment of RO concentrate. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Abatement of phenolic mixtures by catalytic wet oxidation enhanced by Fenton's pretreatment: Effect of H2O2 dosage and temperature

    International Nuclear Information System (INIS)

    Santos, A.; Yustos, P.; Rodriguez, S.; Simon, E.; Garcia-Ochoa, F.

    2007-01-01

    Catalytic wet oxidation (CWO) of a phenolic mixture containing phenol, o-cresol and p-cresol (500 mg/L on each pollutant) has been carried out using a commercial activated carbon (AC) as catalyst, placed in a continuous three-phase reactor. Total pressure was 16 bar and temperature was 127 deg. C. Pollutant conversion, mineralization, intermediate distribution, and toxicity were measured at the reactor outlet. Under these conditions no detoxification of the inlet effluent was found even at the highest catalyst weight (W) to liquid flow rate (Q L ) ratio used. On the other hand, some Fenton Runs (FR) have been carried out in a batch way using the same phenolic aqueous mixture previously cited. The concentration of Fe 2+ was set to 10 mg/L. The influence of the H 2 O 2 amount (between 10 and 100% of the stoichiometric dose) and temperature (30, 50, and 70 deg. C) on phenols conversion, mineralization, and detoxification have been analyzed. Phenols conversion was near unity at low hydrogen peroxide dosage but mineralization and detoxification achieved an asymptotic value at each temperature conditions. The integration of Fenton reagent as pretreatment of the CWO process remarkably improves the efficiency of the CWO reactor and allows to obtain detoxified effluents at mild temperature conditions and relatively low W/Q L values. For a given phenolic mixture a temperature range of 30-50 deg. C in the Fenton pretreatment with a H 2 O 2 dosage between 20 and 40% of the stoichiometric amount required can be proposed

  20. Influence of dihydroxybenzenes on paracetamol and ciprofloxacin degradation and iron(III) reduction in Fenton processes.

    Science.gov (United States)

    Costa E Silva, Beatriz; de Lima Perini, João Angelo; Nogueira, Raquel F Pupo

    2017-03-01

    The degradation of paracetamol (PCT) and ciprofloxacin (CIP) was compared in relation to the generation of dihydroxylated products, Fe(III) reduction and reaction rate in the presence of dihydroxybenzene (DHB) compounds, or under irradiation with free iron (Fe 3+ ) or citrate complex (Fecit) in Fenton or photo-Fenton process. The formation of hydroquinone (HQ) was observed only during PCT degradation in the dark, which increased drastically the rate of PCT degradation, since HQ formed was able to reduce Fe 3+ and contributed to PCT degradation efficiency. When HQ was initially added, PCT and CIP degradation rate in the dark was much higher in comparison to the absence of HQ, due to the higher and faster formation of Fe 2+ at the beginning of reaction. In the absence of HQ, no CIP degradation was observed; however, when HQ was added after 30 min, the degradation rate increased drastically. Ten PCT hydroxylated intermediates were identified in the absence of HQ, which could contribute for Fe(III) reduction and consequently to the degradation in a similar way as HQ. During CIP degradation, only one product of hydroxyl radical attack on benzene ring and substitution of the fluorine atom was identified when HQ was added to the reaction medium.

  1. Natural Hematite and Siderite as Heterogeneous Catalysts for an Effective Degradation of 4-Chlorophenol via Photo-Fenton Process

    Directory of Open Access Journals (Sweden)

    Haithem Bel Hadjltaief

    2018-06-01

    Full Text Available This paper describes a simple and low-cost process for the degradation of 4-Chlorophenol (4-CP from aqueous solution, using natural Tunisian Hematite (M1 and Siderite (M2. Two natural samples were collected in the outcroppings of the Djerissa mining site (Kef district, northwestern Tunisia. Both Hematite and Siderite ferrous samples were characterized using several techniques, including X-Ray Diffraction (XRD, Nitrogen Physisorption (BET, Infrared Spectroscopy (FTIR, H2-Temperature Programmed Reduction (H2-TPR, Scanning Electronic Microscopy (SEM linked with Energy Dispersive X-ray (EDS and High-Resolution Transmission Electron Microscopy (HRTEM. Textural, structural and chemical characterization confirmed the presence of Hematite and Siderite phases with a high amount of iron on the both surface materials. Their activity was evaluated in the oxidation of 4-CP in aqueous medium under heterogeneous photo-Fenton process. Siderite exhibited higher photocatalytic oxidation activity than Hematite at pH 3. The experimental results also showed that 100% conversion of 4-CP and 54% TOC removal can be achieved using Siderite as catalyst. Negligible metal leaching and catalyst reutilization without any loss of activity point towards an excellent catalytic stability for both natural catalysts.

  2. Efficient mineralization of antibiotic ciprofloxacin in acid aqueous medium by a novel photoelectro-Fenton process using a microwave discharge electrodeless lamp irradiation.

    Science.gov (United States)

    Wang, Aimin; Zhang, Yanyu; Zhong, Huihui; Chen, Yu; Tian, Xiujun; Li, Desheng; Li, Jiuyi

    2018-01-15

    In this study, a novel photoelectro-Fenton (PEF) process using microwave discharge electrodeless lamp (MDEL) as a UV irradiation source was developed for the removal of antibiotic ciprofloxacin (CIP) in water. Comparative degradation of 200mgL -1 CIP was studied by direct MDEL photolysis, anodic oxidation (AO), AO in presence of electrogenerated H 2 O 2 (AO-H 2 O 2 ), AO-H 2 O 2 under MDEL irradiation (MDEL-AO-H 2 O 2 ), electro-Fenton (EF) and MDEL-PEF processes. Higher oxidation power was found in the sequence: MDEL photolysis < AO < AO-H 2 O 2 < MDEL-AO-H 2 O 2 < EF < MDEL-PEF. Effects of current density, pH, initial Fe 2+ concentration and initial CIP concentration on TOC removal in MDEL-PEF process were examined, and the optimal conditions were ascertained. The releases of three inorganic ions (F - , NH 4 + and NO 3 - ) and two carboxylic acids (oxalic and formic acids) were qualified. Seven aromatic intermediates mainly generated from hydroxylation, dealkylation and defluorination of CIP were detected by UPLC-QTOF-MS/MS technology. Therefore, plausible degradation sequences for CIP degradation in MDEL-PEF process including all detected products were proposed. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Drinking water and biofilm disinfection by Fenton-like reaction.

    Science.gov (United States)

    Gosselin, F; Madeira, L M; Juhna, T; Block, J C

    2013-10-01

    A Fenton-like disinfection process was conducted with Fenton's reagent (H2O2) at pH 3 or 5 on autochthonous drinking water biofilms grown on corroded or non-corroded pipe material. The biofilm disinfection by Fenton-like oxidation was limited by the low content of iron and copper in the biomass grown on non-corroded plumbing. It was slightly improved by spiking the distribution system with some additional iron source (soluble iron II or ferrihydrite particles appeared as interesting candidates). However successful in situ disinfection of biofilms was only achieved in fully corroded cast iron pipes using H2O2 and adjusting the pH to 5. These new results provide additional support for the use of Fenton's processes for cleaning drinking water distribution systems contaminated with biological agents or organics. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Environmental application of millimetre-scale sponge iron (s-Fe"0) particles (IV): New insights into visible light photo-Fenton-like process with optimum dosage of H_2O_2 and RhB photosensitizers

    International Nuclear Information System (INIS)

    Ju, Yongming; Yu, Yunjiang; Wang, Xiaoyan; Xiang, Mingdeng; Li, Liangzhong; Deng, Dongyang; Dionysiou, Dionysios D.

    2017-01-01

    Highlights: • Synergistic action of Rhodamine B (RhB), visible light, H_2O_2 and s-Fe"0 is essential. • The complexes of RhB and Fe"3"+ eject one electron via ligand-to-metal charge-transfer. • RhB assists the photo-Fenton-like removal of tetrabromobisphenol A (TBBPA). - Abstract: In this study, we firstly develop the photo-Fenton-like system with millimetric sponge iron (s-Fe"0), H_2O_2, visible light (vis, λ ≥ 420 nm) and rhodamine B (RhB), and present a comprehensive study concerning the mechanism. Thus, we investigate (1) the adsorption of RhB onto s-Fe"0, (2) the photo-Fenton-like removal of RhB over iron oxides generated from the corrosion of s-Fe"0, (3) the homogeneous photo-Fenton removal of RhB over Fe"2"+ or Fe"3"+, (4) the Fe"3"+-RhB complexes, and (5) the photo-Fenton-like removal of tetrabromobisphenol A (TBBPA). The results show that neither the adsorption process over s-Fe"0 nor the photo-Fenton-like process over FeOOH, Fe_3O_4 and Fe_2O_3, achieved efficient removal of RhB. For comparison, in homogeneous photo-Fenton process, the presence of Fe"3"+ ions, rather than Fe"2"+ ions, effectively eliminated RhB. Furthermore, the UV–vis spectra showing new absorbance at ∼ 285 nm indicate the complexes of RhB and Fe"3"+ ions, adopting vis photons to form excited state and further eject one electron via ligand-to-metal charge-transfer to activate H_2O_2. Additionally, efficient TBBPA removal was obtained only in the presence of RhB. Accordingly, the s-Fe"0– based photo-Fenton-like process assisted with dyestuff wastewater is promising for removing a series of persistent organic pollutants.

  5. Study of the degradation performance (TOC, BOD, and toxicity) of bisphenol A by the photo-Fenton process.

    Science.gov (United States)

    Pérez-Moya, M; Kaisto, T; Navarro, M; Del Valle, L J

    2017-03-01

    Degradation of bisphenol A (BPA, 0.5 L, 30 mg L -1 ) was studied by photo-Fenton treatment, while Fenton reagents were variables. The efficiency of the degradation process was evaluated by the reduction of total organic carbon (TOC), the biochemical oxygen demand (BOD), and toxicity. For toxicity analysis, bacterial methods were found infeasible, but the in vitro assay of VERO cells culture was successfully applied. Experiments according to a 2 2 design of experiments (DOE) with star points and three center points for statistical validity allowed selecting those process conditions (Fe(II) and H 2 O 2 load) that maximized the process performance. Photo-Fenton process effectively eliminated BPA and partly degraded its by-products (residual TOC TOC = 92 %) was attained. Toxicity was also detected to 50 % of cellular mortality even at long reaction times. However, 40.25 mg L -1 of H 2 O 2 decreased residual TOC to 70 % while cell mortality decreased down to 25 %. With more H 2 O 2 , the residual TOC decreased down to 15 % but cell mortality remained within the 20-25 % level. Photo-Fenton increased the biodegradability and reduced the toxicity of the studied sample.

  6. Recent Overview of Solar Photocatalysis and Solar Photo-Fenton Processes for Wastewater Treatment

    Directory of Open Access Journals (Sweden)

    A. G. Gutierrez-Mata

    2017-01-01

    Full Text Available This literature research, although not exhaustive, gives perspective to solar-driven photocatalysis, such as solar photo-Fenton and TiO2 solar photocatalysis, reported in the literature for the degradation of aqueous organic pollutants. Parameters that influence the degradation and mineralization of organics like catalyst preparation, type and load of catalyst, catalyst phase, pH, applied potential, and type of organic pollutant are addressed. Such parameters may also affect the photoactivity of the catalysts used in the studied solar processes. Solar irradiation is a renewable, abundant, and pollution-free energy source for low-cost commercial applications. Therefore, these solar processes represent an environmentally friendly alternative mainly because the use of electricity can be decreased/avoided.

  7. Effect of Fenton pre-oxidation on mobilization of nutrients and efficient subsequent bioremediation of crude oil-contaminated soil.

    Science.gov (United States)

    Xu, Jinlan; Kong, Fanxing; Song, Shaohua; Cao, Qianqian; Huang, Tinglin; Cui, Yiwei

    2017-08-01

    Fenton pre-oxidation and a subsequent bioremediation phase of 80 days were used to investigate the importance of matching concentration of residual indigenous bacteria and nutrient levels on subsequent bioremediation of crude oil. Experiments were performed using either high (>10 7.7 ± 0.2  CFU/g soil) or low ( 9.8), moderate (C/N:5-9.8), and lacking nutrient level (C/N bioremediation of crude oil. In addition, the biodegradation of long chain molecules (C 26 C 30 ) required a high level of NH 4 + -N. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Treatment of landfill leachate by Fenton's reagent in a continuous stirred tank reactor

    International Nuclear Information System (INIS)

    Zhang Hui; Choi, H.J.; Huang, C.-P.

    2006-01-01

    The treatment of landfill leachate by Fenton process was carried out in a continuous stirred tank reactor (CSTR). The effect of operating conditions such as reaction time, hydraulic retention time, pH, H 2 O 2 to Fe(II) molar ratio, Fenton's reagent dosage, initial COD strength, and temperature on the efficacy of Fenton process was investigated. It is demonstrated that Fenton's reagent can effectively degrade leachate organics. Fenton process reached the steady state after three times of hydraulic retention. The oxidation of organic materials in the leachate was pH dependent and the optimal pH was 2.5. The favorable H 2 O 2 to Fe(II) molar ratio was 3, and organic removal increased as dosage increased at the favorable H 2 O 2 to Fe(II) molar ratio. Temperature gave a positive effect on organic removal

  9. Electro-Fenton, UVA photoelectro-Fenton and solar photoelectro-Fenton degradation of the drug ibuprofen in acid aqueous medium using platinum and boron-doped diamond anodes

    International Nuclear Information System (INIS)

    Skoumal, Marcel; Rodriguez, Rosa Maria; Cabot, Pere Lluis; Centellas, Francesc; Garrido, Jose Antonio; Arias, Conchita; Brillas, Enric

    2009-01-01

    The degradation of a 41 mg dm -3 ibuprofen (2-(4-isobutylphenyl)propionic acid) solution of pH 3.0 has been comparatively studied by electrochemical advanced oxidation processes (EAOPs) like electro-Fenton, UVA photoelectro-Fenton and solar photoelectro-Fenton at constant current density. Experiments were performed in a one-compartment cell with a Pt or boron-doped diamond (BDD) anode and an O 2 -diffusion cathode. Heterogeneous hydroxyl radical (·OH) is generated at the anode surface from water oxidation, while homogeneous ·OH is formed from Fenton's reaction between Fe 2+ and H 2 O 2 generated at the cathode, being its production strongly enhanced from photo-Fenton reaction induced by sunlight. Higher mineralization is attained in all methods using BDD instead Pt, because the former produces greater quantity of ·OH enhancing the oxidation of pollutants. The mineralization rate increases under UVA and solar irradiation by the rapid photodecomposition of complexes of Fe(III) with acidic intermediates. The most potent method is solar photoelectro-Fenton with BDD giving 92% mineralization due to the formation of a small proportion of highly persistent final by-products. The effect of Fe 2+ content, pH and current density on photoelectro-Fenton degradation has been studied. The ibuprofen decay always follows a pseudo-first-order kinetics and its destruction rate is limited by current density and UV intensity. Aromatics such as 1-(1-hydroxyethyl)-4-isobutylbenzene, 4-isobutylacetophenone, 4-isobutylphenol and 4-ethylbenzaldehyde, and carboxylic acids such as pyruvic, acetic, formic and oxalic have been identified as oxidation by-products. Oxalic acid is the ultimate by-product and the fast photodecarboxylation of its complexes with Fe(III) under UVA or solar irradiation explains the higher oxidation power of photoelectro-Fenton methods in comparison to electro-Fenton procedures

  10. A fast and environment-friendly method for determination of chemical oxygen demand by using the heterogeneous Fenton-like process (H2O2/Fe(3-x)Co(x)O4 nanoparticles) as an oxidant.

    Science.gov (United States)

    Esteves, Lorena C R; Oliveira, Thaís R O; Souza, Elias C; Bomfeti, Cleide A; Gonçalves, Andrea M; Oliveira, Luiz C A; Barbosa, Fernando; Pereira, Márcio C; Rodrigues, Jairo L

    2015-04-01

    An easy, fast and environment-friendly method for COD determination in water is proposed. The procedure is based on the oxidation of organic matter by the H2O2/Fe(3-x)Co(x)O4 system. The Fe(3-x)Co(x)O4 nanoparticles activate the H2O2 molecule to produce hydroxyl radicals, which are highly reactive for oxidizing organic matter in an aqueous medium. After the oxidation step, the organic matter amounts can be quantified by comparing the quantity of H2O2 consumed. Moreover, the proposed COD method has several distinct advantages, since it does not use toxic reagents and the oxidation reaction of organic matter is conducted at room temperature and atmospheric pressure. Method detection limit is 2.0 mg L(-1) with intra- and inter-day precision lower than 1% (n=5). The calibration graph is linear in the range of 2.0-50 mg L(-1) with a sample throughput of 25 samples h(-1). Data are validated based on the analysis of six contaminated river water samples by the proposed method and by using a comparative method validated and marketed by Merck, with good agreement between the results (t test, 95%). Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Citric Acid-Modified Fenton's Reaction for the Oxidation of Chlorinated Ethylenes in Soil Solution Systems

    Energy Technology Data Exchange (ETDEWEB)

    Seol, Yongkoo; Javandel, Iraj

    2008-03-15

    Fenton's reagent, a solution of hydrogen peroxide and ferrous iron catalyst, is used for an in-situ chemical oxidation of organic contaminants. Sulfuric acid is commonly used to create an acidic condition needed for catalytic oxidation. Fenton's reaction often involves pressure buildup and precipitation of reaction products, which can cause safety hazards and diminish efficiency. We selected citric acid, a food-grade substance, as an acidifying agent to evaluate its efficiencies for organic contaminant removal in Fenton's reaction, and examined the impacts of using citric acid on the unwanted reaction products. A series of batch and column experiments were performed with varying H{sub 2}O{sub 2} concentrations to decompose selected chlorinated ethylenes. Either dissolved iron from soil or iron sulfate salt was added to provide the iron catalyst in the batch tests. Batch experiments revealed that both citric and sulfuric acid systems achieved over 90% contaminant removal rates, and the presence of iron catalyst was essential for effective decontamination. Batch tests with citric acid showed no signs of pressure accumulation and solid precipitations, however the results suggested that an excessive usage of H{sub 2}O{sub 2} relative to iron catalysts (Fe{sup 2+}/H{sub 2}O{sub 2} < 1/330) would result in lowering the efficiency of contaminant removal by iron chelations in the citric acid system. Column tests confirmed that citric acid could provide suitable acidic conditions to achieve higher than 55% contaminant removal rates.

  12. Performing in-situ chemical oxidation with Fenton's Reagent at a former gas work in Rotterdam

    Energy Technology Data Exchange (ETDEWEB)

    Plaisier, W.; Pancras, T. [In-situ Technieken BV, Wageningen (Netherlands); Bennen, M.; Bouwhuis, E. [Public Works Rotterdam (Netherlands)

    2003-07-01

    In-Situ Technieken BV is the first company in the Netherlands to apply full-scale in-situ chemical oxidation (ISCO) by means of Fenton's reagent or permanganates. The use of ISCO for soil remediation purposes originated in the USA. After three years of practical experience in the Netherlands it can be stated that ISCO has become a proven technology for source area treatment in the Netherlands as well. We present the results of a pilot ISCO treatment program with Fenton's reagent that was performed at the former gas works facility 'Feyenoord'. The site is one of the largest gas works facilities built in Rotterdam. The former gas production activities have lead to severe pollution of soil and groundwater over an area of approximately 3 hectares. Both laboratory and field observations showed that it would be very difficult to execute an efficient Fenton's reagent ISCO treatment program at this specific site for the following reasons. First of all, the contamination consisting of tar and tar-related compounds is found in an anthropogenic (man-made) soil of 9 meter in thickness. Secondly, high contents of carbonates and organic material were found in the soils, which act as a scavenger for the hydroxyl free radical in a Fenton's reagent ISCO system. The pilot test was performed in two phases with an intermediate period of 2 months. The injection of totally 24 tonnes hydrogen peroxide (50%) was anticipated. Reactions of the reagents in the soil were very strong. The presence of old (forgotten) boreholes and an intensive drainage system, in combination with the aggressive reaction resulted in short-circuiting of reagents to the surface. Out of the proposed 24 tonnes of hydrogen peroxide (50%) only 14.5 tonnes were injected. This would have effect on the amount of contamination oxidized. Nevertheless, the oxidation had a significant effect on the soil contamination. A reduction of approximately 90% for PAH was obtained. Reduction was also

  13. Oxidative desulfurization of fuels catalyzed by Fenton-like ionic liquids at room temperature.

    Science.gov (United States)

    Jiang, Yunqing; Zhu, Wenshuai; Li, Huaming; Yin, Sheng; Liu, Hua; Xie, Qingjie

    2011-03-21

    Oxidation of the sulfur-containing compounds benzothiophene (BT), dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT) has been studied in a desulfurization system composed of model oil, hydrogen peroxide, and different types of ionic liquids [(C(8)H(17))(3)CH(3)N]Cl/FeCl(3), [(C(8)H(17))(3)CH(3)N]Cl/CuCl(2), [(C(8)H(17))(3)CH(3)N]Cl/ZnCl(2), [(C(8)H(17))(3)CH(3)N]Cl/SnCl(2), [(C(4)H(9))(3)CH(3)N]Cl/FeCl(3), [C(10)H(21)(CH(3))(3)N]Cl/FeCl(3), [(C(10)H(21))(2)(CH(3))(2)N]Cl/FeCl(3). Deep desulfurization is achieved in the Fenton-like ionic liquid [(C(8)H(17))(3)CH(3)N]Cl/FeCl(3) at 25 °C for 1 h. The desulfurization of DBT reaches 97.9%, in consuming very low amount of [(C(8)H(17))(3)CH(3)N]Cl/FeCl(3) (only 0.702 mmol). The reaction conditions, for example, the amount of [(C(8)H(17))(3)CH(3)N]Cl/FeCl(3) or H(2)O(2), the temperature, and the molar ratio of FeCl(3) to [(C(8)H(17))(3)CH(3)N]Cl, are investigated for this system. The oxidation reactivity of the different sulfur-containing compounds is found to decrease in the order of DBT>BT>4,6-DMDBT. The desulfurization system can be recycled six times without significant decrease in activity. The sulfur level of FCC gasoline could be reduced from 360 ppm to 110 ppm. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Optimization of the mineralization of a mixture of phenolic pollutants under a ferrioxalate-induced solar photo-Fenton process.

    Science.gov (United States)

    Monteagudo, J M; Durán, A; Aguirre, M; San Martín, I

    2011-01-15

    The mineralization of solutions containing a mixture of three phenolic compounds, gallic, p-coumaric and protocatechuic acids, in a ferrioxalate-induced solar photo-Fenton process was investigated. The reactions were carried out in a pilot plant consisting of a compound parabolic collector (CPC) solar reactor. An optimization study was performed combining a multivariate experimental design and neuronal networks that included the following variables: pH, temperature, solar power, air flow and initial concentrations of H(2)O(2), Fe(II) and oxalic acid. Under optimal conditions, total elimination of the original compounds and 94% TOC removal of the mixture were achieved in 5 and 194 min, respectively. pH and initial concentrations of H(2)O(2) and Fe(II) were the most significant factors affecting the mixture mineralization. The molar correlation between consumed hydrogen peroxide and removed TOC was always between 1 and 3. A detailed analysis of the reaction was presented. The values of the pseudo-first-order mineralization kinetic rate constant, k(TOC), increased as initial Fe(II) and H(2)O(2) concentrations and temperature increased. The optimum pH value also slightly increased with greater Fe(II) and hydrogen peroxide concentrations but decreased when temperature increased. OH and O(2)(-) radicals were the main oxidative intermediate species in the process, although singlet oxygen ((1)O(2)) also played a role in the mineralization reaction. Copyright © 2010 Elsevier B.V. All rights reserved.

  15. COMPARATIVE ANALYSIS USING DIPIRONA DEGRADATION PROCESS WITH PHOTO-FENTON UV-C LIGHT AND SOLAR RADIATION

    Directory of Open Access Journals (Sweden)

    Daniella Carla Napoleão

    2015-01-01

    Full Text Available The contamination of water bodies is a major concern on the part of scientists from different parts of the world. Domestic and industrial activities are the cause of the daily pouring of various types of pollutants which are in most cases resistant to conventional treatments of waters. Among the contaminants, especially noteworthy are the drugs in which it is found that 50% to 90% are discarded without treatment. The concerns about these substances are the adverse effects to human health and animals, especially in aquatic environments. The advanced oxidation processes (AOP have been studied and applied as an efficient alternative treatment, in order that it can be applied to the degradation of the different pollutants, considering that can generate hydroxyl radicals, highly reactive even somewhat selective. This study evaluated the efficiency of the photo-Fenton process using UV-C radiation and sunlight to degradation of the drug dipyrone in aqueous solution contaminated with the active ingredient of the drug at a concentration of 20 mg.L-1. Assays were performed with 50 mL aliquots of the solution following 23 factorial designs with central point, and the variables studied: addition of H2O2, adding FeSO4.7H2O and time. The detection and quantification of dipyrone before and after the AOP was performed by high performance liquid chromatography (HPLC and verified that about DE100% degradation of the compound was obtained.

  16. Combination of surfactant enhanced soil washing and electro-Fenton process for the treatment of soils contaminated by petroleum hydrocarbons.

    Science.gov (United States)

    Huguenot, David; Mousset, Emmanuel; van Hullebusch, Eric D; Oturan, Mehmet A

    2015-04-15

    In order to improve the efficiency of soil washing treatment of hydrocarbon contaminated soils, an innovative combination of this soil treatment technique with an electrochemical advanced oxidation process (i.e. electro-Fenton (EF)) has been proposed. An ex situ soil column washing experiment was performed on a genuinely diesel-contaminated soil. The washing solution was enriched with surfactant Tween 80 at different concentrations, higher than the critical micellar concentration (CMC). The impact of soil washing was evaluated on the hydrocarbons concentration in the leachates collected at the bottom of the soil columns. These eluates were then studied for their degradation potential by EF treatment. Results showed that a concentration of 5% of Tween 80 was required to enhance hydrocarbons extraction from the soil. Even with this Tween 80 concentration, the efficiency of the treatment remained very low (only 1% after 24 h of washing). Electrochemical treatments performed thereafter with EF on the collected eluates revealed that the quasi-complete mineralization (>99.5%) of the hydrocarbons was achieved within 32 h according to a linear kinetic trend. Toxicity was higher than in the initial solution and reached 95% of inhibition of Vibrio fischeri bacteria measured by Microtox method, demonstrating the presence of remaining toxic compounds even after the complete degradation. Finally, the biodegradability (BOD₅/COD ratio) reached a maximum of 20% after 20 h of EF treatment, which is not enough to implement a combined treatment with a biological treatment process. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Fenton process-affected transformation of roxarsone in paddy rice soils: Effects on plant growth and arsenic accumulation in rice grain.

    Science.gov (United States)

    Qin, Junhao; Li, Huashou; Lin, Chuxia

    2016-08-01

    Batch and greenhouse experiments were conducted to examine the effects of Fenton process on transformation of roxarsone in soils and its resulting impacts on the growth of and As uptake by a rice plant cultivar. The results show that addition of Fenton reagent markedly accelerated the degradation of roxarsone and produced arsenite, which was otherwise absent in the soil without added Fenton reagent. Methylation of arsenate was also enhanced by Fenton process in the earlier part of the experiment due to abundant supply of arsenate from Roxarsone degradation. Overall, addition of Fenton reagent resulted in the predominant presence of arsenate in the soils. Fenton process significantly improved the growth of rice in the maturity stage of the first crop, The concentration of methylated As species in the rice plant tissues among the different growth stages was highly variable. Addition of Fenton reagent into the soils led to reduced uptake of soil-borne As by the rice plants and this had a significant effect on reducing the accumulation of As in rice grains. The findings have implications for understanding As biogeochemistry in paddy rice field receiving rainwater-borne H2O2 and for development of mitigation strategies to reduce accumulation of As in rice grains. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Application of Fenton process to remove organic matter and PCBs from waste (fuller's earth) contaminated with insulating oil.

    Science.gov (United States)

    da Silva, Milady Renata Apolinário; Rodrigues, Eduardo de Oliveira; Espanhol-Soares, Melina; Silva, Flavio Soares; Kondo, Márcia Matiko; Gimenes, Rossano

    2018-01-09

    Polychlorinated biphenyls (PCBs) are carcinogenic to humans and can be found in fuller's earth used for the treatment of used transformer oil. This work describes an optimization of the Fenton process for the removal of contaminants from fuller's earth. The effects of pH (2.5 and 4.0), [H 2 O 2 ] (1.47 and 2.07 mol L -1 ), and [Fe 2+ ] (1.7 and 40 mmol L -1 ) were studied. The Fenton process efficiency was monitored using the decreases in the chemical oxygen demand (COD) and the concentrations of oil and grease, total carbon (TC), PCBs, and H 2 O 2 . The fuller's earth contaminated with insulating oil presented 35% (w/w) of TC, 34% (w/w) of oil and grease, 297.0 g L -1 COD, and 64 mg of PCBs per kg. The material could therefore be considered a dangerous waste. After Fenton treatment, using a slurry mode, there was a removal of 55% of COD, 20% of oil and grease, and 20% of TC, achieved at pH 2.5 using 2.07 mol L -1 of H 2 O 2 and 40.0 mmol L -1 of Fe 2+ . No PCBs were detected in the samples after the Fenton treatment, even using smaller amounts of Fenton reagents (1.47 mol L -1 of H 2 O 2 , 1.7 mmol L -1 of Fe 2+ , pH 2.5). The results indicated that the treated fuller's earth was free from PCB residues and could be disposed of in a simple landfill, in accordance with Brazilian PCB regulations.

  19. Ex Vivo Antioxidant Activity of Selected Medicinal Plants against Fenton Reaction-Mediated Oxidation of Biological Lipid Substrates

    Directory of Open Access Journals (Sweden)

    Namratha Pai Kotebagilu

    2015-01-01

    Full Text Available Free radical-mediated oxidation is often linked to various degenerative diseases. Biological substrates with lipids as major components are susceptible to oxygen-derived lipid peroxidation due to their composition. Lipid peroxide products act as biomarkers in evaluating the antioxidant potential of various plants and functional foods. The study focused on evaluation of the antioxidant potential of two extracts (methanol and 80% methanol of four medicinal plants, Andrographis paniculata, Costus speciosus, Canthium parviflorum, and Abrus precatorius, against Fenton reaction-mediated oxidation of three biological lipid substrates; cholesterol, low-density lipoprotein, and brain homogenate. The antioxidant activity of the extracts was measured by thiobarbituric acid reactive substances method. Also, the correlation between the polyphenol, flavonoid content, and the antioxidant activity in biological substrates was analyzed. Results indicated highest antioxidant potential by 80% methanol extract of Canthium parviflorum (97.55%, methanol extract of Andrographis paniculata (72.15%, and methanol extract of Canthium parviflorum (49.55% in cholesterol, low-density lipoprotein, and brain, respectively. The polyphenol and flavonoid contents of methanol extract of Andrographis paniculata in cholesterol (r=0.816 and low-density lipoprotein (r=0.948 and Costus speciosus in brain (r=0.977, polyphenols, and r=0.949, flavonoids correlated well with the antioxidant activity. The findings prove the antioxidant potential of the selected medicinal plants against Fenton reaction in biological lipid substrates.

  20. Response surface modeling for optimization heterocatalytic Fenton oxidation of persistence organic pollution in high total dissolved solid containing wastewater.

    Science.gov (United States)

    Sekaran, G; Karthikeyan, S; Boopathy, R; Maharaja, P; Gupta, V K; Anandan, C

    2014-01-01

    The rice-husk-based mesoporous activated carbon (MAC) used in this study was precarbonized and activated using phosphoric acid. N2 adsorption/desorption isotherm, X-ray powder diffraction, electron spin resonance, X-ray photoelectron spectroscopy and scanning electron microscopy, transmission electron microscopy, (29)Si-NMR spectroscopy, and diffuse reflectance spectroscopy were used to characterize the MAC. The tannery wastewater carrying high total dissolved solids (TDS) discharged from leather industry lacks biodegradability despite the presence of dissolved protein. This paper demonstrates the application of free electron-rich MAC as heterogeneous catalyst along with Fenton reagent for the oxidation of persistence organic compounds in high TDS wastewater. The heterogeneous Fenton oxidation of the pretreated wastewater at optimum pH (3.5), H2O2 (4 mmol/L), FeSO4[Symbol: see text]7H2O (0.2 mmol/L), and time (4 h) removed chemical oxygen demand, biochemical oxygen demand, total organic carbon and dissolved protein by 86, 91, 83, and 90%, respectively.

  1. Degradation of ciprofloxacin antibiotic by Homogeneous Fenton oxidation: Hybrid AHP-PROMETHEE method, optimization, biodegradability improvement and identification of oxidized by-products.

    Science.gov (United States)

    Salari, Marjan; Rakhshandehroo, Gholam Reza; Nikoo, Mohammad Reza

    2018-09-01

    The main purpose of this experimental study was to optimize Homogeneous Fenton oxidation (HFO) and identification of oxidized by-products from degradation of Ciprofloxacin (CIP) using hybrid AHP-PROMETHEE, Response Surface Methodology (RSM) and High Performance Liquid Chromatography coupled with Mass Spectrometry (HPLC-MS). At the first step, an assessment was made for performances of two catalysts (FeSO 4 ·7H 2 O and FeCl 2 ·4H 2 O) based on hybrid AHP-PROMETHEE decision making method. Then, RSM was utilized to examine and optimize the influence of different variables including initial CIP concentration, Fe 2+ concentration, [H 2 O 2 ]/[ Fe 2+ ] mole ratio and initial pH as independent variables on CIP removal, COD removal, and sludge to iron (SIR) as the response functions in a reaction time of 25 min. Weights of the mentioned responses as well as cost criteria were determined by AHP model based on pairwise comparison and then used as inputs to PROMETHEE method to develop hybrid AHP-PROMETHEE. Based on net flow results of this hybrid model, FeCl 2 ·4H 2 O was more efficient because of its less environmental stability as well as lower SIR production. Then, optimization of experiments using Central Composite Design (CCD) under RSM was performed with the FeCl 2 ·4H 2 O catalyst. Biodegradability of wastewater was determined in terms of BOD 5 /COD ratio, showing that HFO process is able to improve wastewater biodegradability from zero to 0.42. Finally, the main intermediaries of degradation and degradation pathways of CIP were investigated with (HPLC-MS). Major degradation pathways from hydroxylation of both piperazine and quinolonic rings, oxidation and cleavage of the piperazine ring, and defluorination (OH/F substitution) were suggested. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Enzymatic in-situ generation of H2O2 for decolorization of Acid Blue 113 by fenton process

    Directory of Open Access Journals (Sweden)

    Karimi Afzal

    2012-01-01

    Full Text Available Decolorization of Acid Blue 113 in an aqueous medium by bio-Fenton process has been investigated in this research. Enzymatic oxidation of glucose was performed to in-situ generation of H2O2 which was employed to react with Fe2+ for producing hydroxyl radicals. The effect of various parameters include concentrations of 113, glucose, and FeSO4, activity of glucose oxidase (GOx and the effect of pH were assessed. The highest decolorization of AB 113 were achieved at Fe2+ concentration of 0.2 mmol/L, pH =4.0, glucose concentration of 0.018 mol/L, and glucose oxidase activity of 2500 U/L in the constant temperature (23 ±0.1ºC and constant shaking rate (160 r/min, while the concentration of 113 was 40 mg/L. In these conditions, 113 decolorization efficiency after 60 min was obtained about 95%.

  3. Industrial detergent wastewater treatment via fenton reagent

    International Nuclear Information System (INIS)

    Mohd Zairie Mohd Yusuff; Mohd Zulkifli Mohamad Noor; Izirwan Izhab

    2010-01-01

    Production of detergent can generates wastewater containing an organic matter with will consume an oxidation demand, surfactants, suspended solids, fat and oil. Besides, sulfate concentration is high in the most detergent plant effluent because of the sulphonation process that has physiological and toxic effects on marine organisms. Therefore, a research must be conducted to find the solution for this problem. The feasibility of Fentons reagent to treat detergent waste was investigated in this study. The sample of detergent wastewater was taken from FPG Oleo chemicals Sdn. Bhd. This experiment studied the effect of temperature towards the feasibility of Fentons reagent process besides the dosage between hydrogen peroxide (H 2 O 2 ) and ferrous ion (Fe 2+ ) in the reagent. While, evaluated efficiency of Fentons reagent in term of chemical oxygen demand (COD), total suspended solid (TSS) and the turbidity reduction within the experimental design. The result found that overall removal was achieved until 96.2 % in term of COD, 98.1 % in term of TSS and 99.6 % in term of turbidity using Fentons reagent process. Besides, also found that this process is optimum at temperature 35 degree Celsius are able to achieve the Standard A of Parameter Limit of Effluent of Standard A and Standard B were outlined by Department of Environment Malaysia (DOE) based on Environment Quality Act 1974. (author)

  4. Fenton and Fenton-like oxidation of pesticide acetamiprid in water samples: kinetic study of the degradation and optimization using response surface methodology.

    Science.gov (United States)

    Mitsika, Elena E; Christophoridis, Christophoros; Fytianos, Konstantinos

    2013-11-01

    The aims of this study were (a) to evaluate the degradation of acetamiprid with the use of Fenton reaction, (b) to investigate the effect of different concentrations of H2O2 and Fe(2+), initial pH and various iron salts, on the degradation of acetamiprid and (c) to apply response surface methodology for the evaluation of degradation kinetics. The kinetic study revealed a two-stage process, described by pseudo- first and second order kinetics. Different H2O2:Fe(2+) molar ratios were examined for their effect on acetamiprid degradation kinetics. The ratio of 3 mg L(-1) Fe(2+): 40 mg L(-1) H2O2 was found to completely remove acetamiprid at less than 10 min. Degradation rate was faster at lower pH, with the optimal value at pH 2.9, while Mohr salt appeared to degrade acetamiprid faster. A central composite design was selected in order to observe the effects of Fe(2+) and H2O2 initial concentration on acetamiprid degradation kinetics. A quadratic model fitted the experimental data, with satisfactory regression and fit. The most significant effect on the degradation of acetamiprid, was induced by ferrous iron concentration followed by H2O2. Optimization, aiming to minimize the applied ferrous concentration and the process time, proposed a ratio of 7.76 mg L(-1) Fe(II): 19.78 mg L(-1) H2O2. DOC is reduced much more slowly and requires more than 6h of processing for 50% degradation. The use to zero valent iron, demonstrated fast kinetic rates with acetamiprid degradation occurring in 10 min and effective DOC removal. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. A Comparison of Central Composite Design and Taguchi Method for Optimizing Fenton Process

    Directory of Open Access Journals (Sweden)

    Anam Asghar

    2014-01-01

    Full Text Available In the present study, a comparison of central composite design (CCD and Taguchi method was established for Fenton oxidation. Dyeini, Dye : Fe+2, H2O2 : Fe+2, and pH were identified control variables while COD and decolorization efficiency were selected responses. L9 orthogonal array and face-centered CCD were used for the experimental design. Maximum 99% decolorization and 80% COD removal efficiency were obtained under optimum conditions. R squared values of 0.97 and 0.95 for CCD and Taguchi method, respectively, indicate that both models are statistically significant and are in well agreement with each other. Furthermore, Prob > F less than 0.0500 and ANOVA results indicate the good fitting of selected model with experimental results. Nevertheless, possibility of ranking of input variables in terms of percent contribution to the response value has made Taguchi method a suitable approach for scrutinizing the operating parameters. For present case, pH with percent contribution of 87.62% and 66.2% was ranked as the most contributing and significant factor. This finding of Taguchi method was also verified by 3D contour plots of CCD. Therefore, from this comparative study, it is concluded that Taguchi method with 9 experimental runs and simple interaction plots is a suitable alternative to CCD for several chemical engineering applications.

  6. Advanced oxidation processes for treatment of petroleum refinery sour waters; Processos oxidativos avancados para tratamento de aguas acidas de refinaria de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Antonio V.; Coelho, Alessandra D.; Sant' Anna Junior, Geraldo L.; Dezotti, Marcia [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Programa de Engenharia Quimica

    2004-07-01

    The characteristics of the waste water generated by the petroleum refineries are related to the type and amount of processed oil, to the nature and the efficiency of the refining operation. The effluents are composed basically of oily waters, originating from of the contact with the oil. Among them, the current of sour water is one of the most preoccupying due to its composition: sulfide, ammonia, mercaptans, phenol, dissolved oil, basic pH, dissolved organic carbon (DOC) and chemical oxygen demand (COD) high. The aim of this work was to evaluate the advanced oxidation processes to degrade sour water (UV radiation, H{sub 2}O{sub 2} and H{sub 2}O{sub 2}/UV, photocatalysis, Fenton and photo-Fenton). All process, except Fenton and photo-Fenton, did not supply satisfactory results, reducing 25% of initial DOC, which it is of 450 mg/L. The results using the Fenton process reached removal of 50% of the initial COD, and when photo- Fenton process obtaining removal of 90%. The processes Fenton and photo-Fenton were shown capable to degrade this kind of waste water, minimizing the environmental problems and corrosion, operating as a pre-treatment for the biological system, or acting alone to degrade the organic matter contained, seeking the water reuse. The effluent used in this work came from Duque de Caxias Refinery (Reduc)/PETROBRAS. (author)

  7. Impact of some herbicides on the biomass activity in biological treatment plants and biodegradability enhancement by a photo-Fenton process.

    Science.gov (United States)

    Benzaquén, T B; Benzzo, M T; Isla, M A; Alfano, O M

    2013-01-01

    In recent years, the use of agrochemicals has increased because they are essential for profitable agricultural production. Herbicides are heavily demanded compounds and among these, the most marketed are 2,4-D, atrazine and acetochlor. They have characteristics that can cause problems to humans and the environment. Therefore, it is necessary to design systems that can reduce these compounds to harmless molecules. This work aims at evaluating the possibility of incorporating these herbicides into degradable effluents in a biological treatment system, without reducing its efficiency. For this purpose, studies of organic matter degradability in the presence of these agrochemicals were performed. A synthetic effluent based on glucose and mineral salts was inoculated with microorganisms. Glucose consumption and biomass concentration were assessed. Subsequently, preliminary studies were performed to test the viability of degradation of the most harmful compound with an advanced oxidation process (AOP). The results showed that the incorporation of these herbicides into degradable effluents in a biological treatment system has a negative impact on microorganisms. Therefore, the application of an AOP, such as the Fenton or photo-Fenton processes, prior to a biological treatment was found to degrade these substances to simpler and less toxic molecules.

  8. The Potential of Fe-exchanged Y Zeolite as a Heterogeneous Fenton-type Catalyst for Oxidative Degradation of Reactive Dye in Water

    OpenAIRE

    Aleksić, M.; Koprivanac, N.; Lončarić Božić, A.; Kušić, H.

    2010-01-01

    The study aimed to investigate the potential of Fe-exchanged zeolites of Y-type as a catalyst in heterogeneous Fenton-type processes for the degradation of model organic pollutant, reactive azo dye C.I. Reactive Blue 137, in water. The research work was directed to investigate the influence of process variables, such as FeY catalyst dosage, Fenton reagent ratio, and initial operating pH on the efficiency of the treatment process. The performance of the studied heterogeneous process was compar...

  9. Optimisation of decolourisation and degradation of Reactive Black 5 dye under electro-Fenton process using Fe alginate gel beads.

    Science.gov (United States)

    Iglesias, O; Fernández de Dios, M A; Rosales, E; Pazos, M; Sanromán, M A

    2013-04-01

    The aim of this work was to improve the ability of the electro-Fenton process using Fe alginate gel beads for the remediation of wastewater contaminated with synthetic dyes and using a model diazo dye such as Reactive Black 5 (RB5). Batch experiments were conducted to study the effects of main parameters, such as voltage, pH and iron concentration. Dye decolourisation, reduction of chemical oxygen demand (COD) and energy consumption were studied. Central composite face-centred experimental design matrix and response surface methodology were applied to design the experiments and to evaluate the interactive effects of the three studied parameters. A total of 20 experimental runs were set, and the kinetic data were analysed using first-order and second-order models. In all cases, the experimental data were fitted to the empirical second-order model with a suitable degree for the maximum decolourisation of RB5, COD reduction and energy consumption by electro-Fenton-Fe alginate gel beads treatment. Working with the obtained empirical model, the optimisation of the process was carried out. The second-order polynomial regression model suggests that the optimum conditions for attaining maximum decolourisation, COD reduction and energy consumption are voltage, 5.69 V; pH 2.24 and iron concentration, 2.68 mM. Moreover, the fixation of iron on alginate beads suggests that the degradation process can be developed under this electro-Fenton process in repeated batches and in a continuous mode.

  10. Comparative study on the removal of COD from POME by electrocoagulation and electro-Fenton methods: Process optimization

    Science.gov (United States)

    Chairunnisak, A.; Arifin, B.; Sofyan, H.; Lubis, M. R.; Darmadi

    2018-03-01

    This research focuses on the Chemical Oxygen Demand (COD) treatment in palm oil mill effluent by electrocoagulation and electro-Fenton methods to solve it. Initially, the aqueous solution precipitates in acid condition at pH of about two. This study focuses on the palm oil mill effluent degradation by Fe electrodes in a simple batch reactor. This work is conducted by using different parameters such as voltage, electrolyte concentration of NaCl, volume of H2O2 and operation time. The processing of data resulted is by using response surface method coupled with Box-Behnken design. The electrocoagulation method results in the optimum COD reduction of 94.53% from operating time of 39.28 minutes, 20 volts, and without electrolyte concentration. For electro-Fenton process, experiment points out that voltage 15.78 volts, electrolyte concentration 0.06 M and H2O2 volume 14.79 ml with time 35.92 minutes yield 99.56% degradation. The result concluded that the electro-Fenton process was more effective to degrade COD of the palm-oil-mill effluent compared to electrocoagulation process.

  11. Integration of processes induced air flotation and photo-Fenton for treatment of residual waters contaminated with xylene

    International Nuclear Information System (INIS)

    Silva, Syllos S. da; Chiavone-Filho, Osvaldo; Barros Neto, Eduardo L. de; Nascimento, Claudio A.O.

    2012-01-01

    Highlights: ► We have studied the treatment of wastewater contaminated with hydrocarbons represented by the xylene, using these processes in an integrated mode: induced air flotation and photo-Fenton. ► We have selected xylene as representative contaminant due to properties of toxicity, solubility in water and vapor pressure. ► The manuscript presents a series of accurate experimental data that can be useful for material and energy optimization purposes in the xylene removal aiming the treatment of oil field produced water. - Abstract: Produced water in oil fields is one of the main sources of wastewater generated in the industry. It contains several organic compounds, such as benzene, toluene, ethyl benzene and xylene (BTEX), whose disposal is regulated by law. The aim of this study is to investigate a treatment of produced water integrating two processes, i.e., induced air flotation (IAF) and photo-Fenton. The experiments were conducted in a column flotation and annular lamp reactor for flotation and photodegradation steps, respectively. The first order kinetic constant of IAF for the wastewater studied was determined to be 0.1765 min −1 for the surfactant EO 7. Degradation efficiencies of organic loading were assessed using factorial planning. Statistical data analysis shows that H 2 O 2 concentration is a determining factor in process efficiency. Degradations above 90% were reached in all cases after 90 min of reaction, attaining 100% mineralization in the optimized concentrations of Fenton reagents. Process integration was adequate with 100% organic load removal in 20 min. The results of the integration of the IAF with the photo-Fenton allowed to meet the effluent limits established by Brazilian legislation for disposal.

  12. Integration of processes induced air flotation and photo-Fenton for treatment of residual waters contaminated with xylene

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Syllos S. da [Departamento Engenharia Quimica, NUPEG, Universidade Federal do Rio Grande do Norte, Campus Universitario, Lagoa Nova, Natal 59066-800, RN (Brazil); Chiavone-Filho, Osvaldo, E-mail: osvaldo@eq.ufrn.br [Departamento Engenharia Quimica, NUPEG, Universidade Federal do Rio Grande do Norte, Campus Universitario, Lagoa Nova, Natal 59066-800, RN (Brazil); Barros Neto, Eduardo L. de [Departamento Engenharia Quimica, NUPEG, Universidade Federal do Rio Grande do Norte, Campus Universitario, Lagoa Nova, Natal 59066-800, RN (Brazil); Nascimento, Claudio A.O. [Departamento de Engenharia Quimica, Escola Politecnica, Universidade de Sao Paulo, Cidade Universitaria, Sao Paulo 05508-900, SP (Brazil)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer We have studied the treatment of wastewater contaminated with hydrocarbons represented by the xylene, using these processes in an integrated mode: induced air flotation and photo-Fenton. Black-Right-Pointing-Pointer We have selected xylene as representative contaminant due to properties of toxicity, solubility in water and vapor pressure. Black-Right-Pointing-Pointer The manuscript presents a series of accurate experimental data that can be useful for material and energy optimization purposes in the xylene removal aiming the treatment of oil field produced water. - Abstract: Produced water in oil fields is one of the main sources of wastewater generated in the industry. It contains several organic compounds, such as benzene, toluene, ethyl benzene and xylene (BTEX), whose disposal is regulated by law. The aim of this study is to investigate a treatment of produced water integrating two processes, i.e., induced air flotation (IAF) and photo-Fenton. The experiments were conducted in a column flotation and annular lamp reactor for flotation and photodegradation steps, respectively. The first order kinetic constant of IAF for the wastewater studied was determined to be 0.1765 min{sup -1} for the surfactant EO 7. Degradation efficiencies of organic loading were assessed using factorial planning. Statistical data analysis shows that H{sub 2}O{sub 2} concentration is a determining factor in process efficiency. Degradations above 90% were reached in all cases after 90 min of reaction, attaining 100% mineralization in the optimized concentrations of Fenton reagents. Process integration was adequate with 100% organic load removal in 20 min. The results of the integration of the IAF with the photo-Fenton allowed to meet the effluent limits established by Brazilian legislation for disposal.

  13. Pyrimethanil degradation by photo-Fenton process: Influence of iron and irradiance level on treatment cost.

    Science.gov (United States)

    Cabrera Reina, A; Miralles-Cuevas, S; Casas López, J L; Sánchez Pérez, J A

    2017-12-15

    This study evaluates the combined effect of photo-catalyst concentration and irradiance level on photo-Fenton efficiency when this treatment is applied to industrial wastewater decontamination. Three levels of irradiance (18, 32 and 46W/m 2 ) and three iron concentrations (8, 20 and 32mg/L) were selected and their influence over the process studied using a raceway pond reactor placed inside a solar box. For 8mg/L, it was found that there was a lack of catalyst to make use of all the available photons. For 20mg/L, the treatment always improved with irradiance indicating that the process was photo-limited. For 32mg/L, the excess of iron caused an excess of radicals production which proved to be counter-productive for the overall process efficiency. The economic assessment showed that acquisition and maintenance costs represent the lowest relative values. The highest cost was found to be the cost of the reagents consumed. Both sulfuric acid and sodium hydroxide are negligible in terms of costs. Iron cost percentages were also very low and never higher than 10.5% while the highest cost was always that of hydrogen peroxide, representing at least 85% of the reagent costs. Thus, the total costs were between 0.76 and 1.39€/m 3 . Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Degradation of Anthraquinone Dye Reactive Blue 4 in Pyrite Ash Catalyzed Fenton Reaction

    Directory of Open Access Journals (Sweden)

    Milena Becelic-Tomin

    2014-01-01

    Full Text Available Pyrite ash (PA is created by burning pyrite in the chemical production of sulphuric acid. The high concentration of iron oxide, mostly hematite, present in pyrite ash, gives the basis for its application as a source of catalytic iron in a modified Fenton process for anthraquinone dye reactive blue 4 (RB4 degradation. The effect of various operating variables such as catalyst and oxidant concentration, initial pH and RB4 concentration on the abatement of total organic carbon, and dye has been assessed in this study. Here we show that degradation of RB4 in the modified Fenton reaction was efficient under the following conditions: pH=2.5; [PA]0=0.2 g L−1; [H2O2]0=5 mM and initial RB4 concentration up to 100 mg L−1. The pyrite ash Fenton reaction can overcome limitations observed from the classic Fenton reaction, such as the early termination of the Fenton reaction. Metal (Pb, Zn, and Cu content of the solution after the process suggests that an additional treatment step is necessary to remove the remaining metals from the water. These results provide basic knowledge to better understand the modified, heterogeneous Fenton process and apply the PA Fenton reaction for the treatment of wastewaters which contains anthraquinone dyes.

  15. Integration of processes induced air flotation and photo-Fenton for treatment of residual waters contaminated with xylene.

    Science.gov (United States)

    da Silva, Syllos S; Chiavone-Filho, Osvaldo; de Barros Neto, Eduardo L; Nascimento, Claudio A O

    2012-01-15

    Produced water in oil fields is one of the main sources of wastewater generated in the industry. It contains several organic compounds, such as benzene, toluene, ethyl benzene and xylene (BTEX), whose disposal is regulated by law. The aim of this study is to investigate a treatment of produced water integrating two processes, i.e., induced air flotation (IAF) and photo-Fenton. The experiments were conducted in a column flotation and annular lamp reactor for flotation and photodegradation steps, respectively. The first order kinetic constant of IAF for the wastewater studied was determined to be 0.1765 min(-1) for the surfactant EO 7. Degradation efficiencies of organic loading were assessed using factorial planning. Statistical data analysis shows that H(2)O(2) concentration is a determining factor in process efficiency. Degradations above 90% were reached in all cases after 90 min of reaction, attaining 100% mineralization in the optimized concentrations of Fenton reagents. Process integration was adequate with 100% organic load removal in 20 min. The results of the integration of the IAF with the photo-Fenton allowed to meet the effluent limits established by Brazilian legislation for disposal. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Comparative study of radical oxidation of DNA and its nucleosides by hydroxyl radicals and ferryl ions generated by the Fenton reaction

    International Nuclear Information System (INIS)

    Mouret, J.F.; Berger, M.; Anselmino, C.; Polverelli, M.; Cadet, J.

    1991-01-01

    A comparative study of the reaction of hydroxyl radicals and Fenton type oxidative species with DNA and 2'-deoxyribonucleosides was investigated. This study was based on the characterization of the diamagnetic products resulting from the chemical transformation of the transient radicals. Emphasis was placed on the radical oxidative reactions of the purine nucleosides. It is interesting to note that oxidative purine radicals can be reduced by reagents such as ascorbic acid or N,N,N',N'-tetramethyl-1, 4-p-phenylenediamine. The observed differences in the nature of the decomposition products resulting from the Fenton reaction are not consistent with the nature of the oxidative species (hydroxyl radicals or ferryl ions) involved, but due to the presence of ferrous sulfate [fr

  17. Mineralization of hetero bi-functional reactive dye in aqueous solution by Fenton and photo-Fenton reactions.

    Science.gov (United States)

    Torrades, Francesc; García-Hortal, José Antonio; García-Montaño, Julia

    2015-01-01

    This study focused on the advanced oxidation of the hetero bi-functional reactive dye Sumifix Supra Yellow 3RF (CI Reactive Yellow 145) using dark Fenton and photo-Fenton conditions in a lab-scale experiment. A 2(3) factorial design was used to evaluate the effects of the three key factors: temperature, Fe(II) and H2O2 concentrations, for a dye concentration of 250 mg L(-1) with chemical oxygen demand (COD) of 172 mg L(-1) O2 at pH=3. The response function was the COD reduction. This methodology lets us find the effects and interactions of the studied variables and their roles in the efficiency of the treatment process. In the optimization, the correlation coefficients for the model (R2) were 0.948 and 0.965 for Fenton and photo-Fenton treatments, respectively. Under optimized reaction conditions: pH=3, temperature=298 K, [H2O2]=11.765 mM and [Fe(II)]=1.075 mM; 60 min of treatment resulted in a 79% and 92.2% decrease in COD, for the dye taken as the model organic compound, after Fenton and photo-Fenton treatments, respectively.

  18. Evaluation of herbicides photodegradation by photo-Fenton process using multivariate analysis

    Energy Technology Data Exchange (ETDEWEB)

    Paterlini, W.C.; Nogueira, R.F.P. [Inst. of Chemistry, Sao Paulo State Univ., R. Prof. Francisco Degni s/n, Araraquara, SP (Brazil)

    2003-07-01

    The photodegradation of herbicides in aqueous medium by photo-Fenton process using ferrioxalate complex (FeOx) as a source of Fe{sup 2+} was evaluated under blacklight irradiation. The commercial products of the herbicides tebuthiuron, 2,4-D and diuron were used. Multivariate analysis was used to evaluate the role of two variables in the photodegradation process, FeOx and hydrogen peroxide concentrations, and to define the concentration ranges that result in the most efficient photodegradation of the herbicides. The photodegradation of the herbicides was followed by monitoring the decrease of the original compounds concentration by HPLC, by the determination of remaining total organic carbon content (TOC), and by the chloride ion release. Under optimised conditions, 20 minutes irradiation was enough to remove 92.7% of TOC for 2,4 D and 89.5% for diuron. Complete dechlorination of these compounds was achieved after 10 minutes of irradiation. It was observed that the initial concentration of these compounds and tebuthiuron was reduced to less than 15% after only 1 minute of irradiation. (orig.)

  19. Application of a hybrid Electrocoagulation-Fenton process in yarn dye wastewater: Kinetic study

    Science.gov (United States)

    Riadi, L.; Sapei, L.; Lidiawati, T.; Agustin, Y. E.

    2016-11-01

    Reactive dyes contain a significant portion of colorants used in yarn dying process and also in textile industry. Since the COD content is usually high in such wastewater,we conducted a hybrid electrocoagulation-fenton method to treat the wastewater. This work describes the application of the hybrid system to the removal of chemical oxygen demand and color from the wastewater in a batch reactor. Having worked with initial pH of 3,0; temperature at 30°C, molar ratio of Fe2+/H2O2 =1/10 and the mol ratio H2O2/COD = 4, we got 88.3% COD conversion and 88.5% color removal. The COD degradation process can be explained in two phases, the first phase is instantaneous reaction and the second phase is first order reaction. The kinetic constant was 0.0053 minute-1 and the rate of COD degradation was 0.0053[COD] mg/L minute.

  20. Combined zero-valent iron and fenton processes for the treatment of Brazilian TNT industry wastewater

    International Nuclear Information System (INIS)

    Barreto-Rodrigues, Marcio; Silva, Flavio T.; Paiva, Teresa C.B.

    2009-01-01

    The environmental impact caused by the production of explosives made from nitroaromatic compounds such as 2,4,6-trinitrotoluene (TNT) is currently a major concern, mainly due to their toxic nature, a fact that makes these compounds highly harmful. This work evaluated a continual system treatment reactor (CSTR) consisting of column zero-valent iron and a system to promote a fenton reaction in order to create possible definitive routines for treating effluents originating from the TNT production process. The spectrophotometric results demonstrated that this combination of processes was highly efficient in promoting the removal of all the absorbed species at 290 nm and the visible region of the specter. The results also revealed that the combination of treatments was significantly efficient in terms of correcting the effluent's main parameters of relevance, mainly COD (95.5% reduction) and TNT concentration, whose total was converted into nitrous and phenolic compounds and, additionally, the acute toxicity was also significantly reduced (95%). These results indicate that the strategy can serve as an efficient option for effluent treatment, for release into the receiving body, or eventually for use as industrial reuse water.

  1. Mineralisation of 2,4-dichlorophenoxyacetic acid by acoustic or hydrodynamic cavitation in conjunction with the advanced Fenton process.

    Science.gov (United States)

    Bremner, David H; Carlo, Stefano Di; Chakinala, Anand G; Cravotto, Giancarlo

    2008-04-01

    The mineralisation of 2,4-dichlorophenoxyacetic acid (2,4-D) in the presence of zero-valent iron and hydrogen peroxide (the advanced Fenton process--AFP) whilst being subjected to acoustic or hydrodynamic cavitation is reported. If the reaction is merely stirred then there is 57% removal of TOC whilst on irradiation the figure is 64% although the latter reaction is more rapid. Use of ultrasound alone results in only 11% TOC removal in 60 min of treatment time. Addition of iron powder marginally enhances the extent of degradation but an appreciable increase is observed in the presence of hydrogen peroxide which acts as a source for hydroxyl radicals by Fenton chemistry as well as by dissociation in the presence of ultrasound. The use of hydrodynamic cavitation in conjunction with the advanced Fenton process has also been found to be a useful tool for continuous remediation of water contaminated with 2,4-D. After 20 min of treatment the residual TOC is reduced to 30% and this probably represents the remaining highly recalcitrant small organic molecules.

  2. Comparison of Fenton process and adsorption method for treatment of industrial container and drum cleaning industry wastewater.

    Science.gov (United States)

    Güneş, Elçin; Çifçi, Deniz İzlen; Çelik, Suna Özden

    2018-04-01

    The present study aims to explore the characterization of industrial container and drum cleaning (ICDC) industry wastewater and treatment alternatives of this wastewater using Fenton and adsorption processes. Wastewater derived from ICDC industry is usually treated by chemical coagulation and biological treatment in Turkey and then discharged in a centralized wastewater treatment facility. It is required that the wastewater COD is below 1500 mg/L to treat in a centralized wastewater treatment facility. The wastewater samples were characterized for parameters of pH, conductivity, COD, BOD 5 , TSS, NH 3 -N, TN, TOC, TP, Cd, Cr, Cu, Fe, Ni, Pb, Zn, and Hg. Initial COD values were in the range of 11,300-14,200 mg/L. The optimum conditions for Fenton treatment were 35-40 g/L for H 2 O 2 , 2-5 g/L for Fe 2+ , and 13-36 for H 2 O 2 /Fe 2+ molar ratio. The optimum conditions of PAC doses and contact times in adsorption studies were 20-30 g/L and 5-12 h, respectively. Removal efficiencies of characterized parameters for the three samples were compared for both Fenton and adsorption processes under optimum conditions. The results suggest that these wastewaters are suitable for discharge to a centralized wastewater treatment plant.

  3. Enhancement of oxygen diffusion process on a rotating disk electrode for the electro-Fenton degradation of tetracycline

    International Nuclear Information System (INIS)

    Zhang, Yan; Gao, Ming-Ming; Wang, Xin-Hua; Wang, Shu-Guang; Liu, Rui-Ting

    2015-01-01

    An electro-Fenton process was developed for wastewater treatment in which hydrogen peroxide was generated in situ with a rotating graphite disk electrode as cathode. The maximum H 2 O 2 generation rate for the RDE reached 0.90 mg/L/h/cm 2 under the rotation speed of 400 rpm at pH 3, and −0.8 V vs SCE. The performance of this electro-Fenton reactor was assessed by tetracycline degradation in an aqueous solution. Experimental results showed the rotation of disk cathode resulted in the efficient production of H 2 O 2 without oxygen aeration, and excellent ability for degrading organic pollutants compared to the electro-Fenton system with fixed cathode. Tetracycline of 50 mg/L was degraded completely within 2 h with the addition of ferrous ion (1.0 mM). The chronoamperometry analysis was employed to investigate the oxygen diffusion on the rotating cathode. The results demonstrated that the diffusion coefficients of dissolved oxygen is 19.45 × 10 −5 cm 2 /s, which is greater than that reported in the literature. Further calculation indicated that oxygen is able to diffuse through the film on the rotating cathode within the contact time in each circle. This study proves that enhancement of oxygen diffusion on RDE is benefit for H 2 O 2 generation, thus provides a promising method for organic pollutants degradation by the combination of RDE with electro-Fenton reactor and offers a new insight on the oxygen transform process in this new system.

  4. Fenton's Reagent. Innovative Technology Summary Report

    International Nuclear Information System (INIS)

    None

    1999-01-01

    The Fenton's Reagent DNAPL treatment process is an in situ oxidation method to destroy DNAPLs in groundwater. Residual industrial solvents, primarily Dense Non-Aqueous Phase Liquids (DNAPLs), are currently the most significant barrier to successful completion of most large groundwater and soil cleanup efforts. DNAPL pools and residues slowly dissolve into surrounding groundwater to create large plumes of organic solvent contamination with concentration levels far above regulatory limits

  5. A novel and quick method to avoid H2O2 interference on COD measurement in Fenton system by Na2SO3 reduction and O2 oxidation

    DEFF Research Database (Denmark)

    Wang, Yong; Li, Weiguang; Angelidaki, Irini

    2013-01-01

    Hydrogen peroxide interference on chemical oxygen demand (COD) measurement has been a big problem in the application of the Fenton process. However, there is no simple and effective method available to address this problem, although several methods have been reported in the literature. In this st......Hydrogen peroxide interference on chemical oxygen demand (COD) measurement has been a big problem in the application of the Fenton process. However, there is no simple and effective method available to address this problem, although several methods have been reported in the literature...... to be effective in the matrix of Fenton treating real landfill leachate. Meanwhile, the procedure for this method in other applications was proposed in detail. To the best of our knowledge, this newly developed method is the most simple and effective way to avoid H2O2 interference on COD analysis....

  6. Decolorization of azo dyes Orange G using hydrodynamic cavitation coupled with heterogeneous Fenton process.

    Science.gov (United States)

    Cai, Meiqiang; Su, Jie; Zhu, Yizu; Wei, Xiaoqing; Jin, Micong; Zhang, Haojie; Dong, Chunying; Wei, Zongsu

    2016-01-01

    The present work demonstrates the application of the combination of hydrodynamic cavitation (HC) and the heterogeneous Fenton process (HF, Fe(0)/H2O2) for the decolorization of azo dye Orange G (OG). The effects of main affecting operation conditions such as the inlet fluid pressure, initial concentration of OG, H2O2 and zero valent iron (ZVI), the fixed position of ZVI, and medium pH on decolorization efficiency were discussed with guidelines for selection of optimum parameters. The results revealed that the acidic conditions are preferred for OG decolorizaiton. The decolorization rate increased with increasing H2O2 and ZVI concentration and decreased with increasing OG initial concentration. Besides, the decolorization rate was strongly dependent on the fixed position of ZVI. The analysis results of degradation products using liquid chromatography-ESI-TOF mass spectrometry revealed that the degradation mechanism of OG proceeds mainly via reductive cleavage of the azo linkage due to the attack of hydroxyl radical. The present work has conclusively established that the combination of HC and HF can be more energy efficient and gives higher decolorization rate of OG as compared with HC and HF alone. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Optimization of the mineralization of a mixture of phenolic pollutants under a ferrioxalate-induced solar photo-Fenton process

    Energy Technology Data Exchange (ETDEWEB)

    Monteagudo, J.M., E-mail: josemaria.monteagudo@uclm.es [University of Castilla-La Mancha, Grupo IMAES, Department of Chemical Engineering, Escuela Tecnica Superior de Ingenieros Industriales, Avda. Camilo Jose Cela, 1, 13071 Ciudad Real (Spain); Duran, A.; Aguirre, M.; San Martin, I. [University of Castilla-La Mancha, Grupo IMAES, Department of Chemical Engineering, Escuela Tecnica Superior de Ingenieros Industriales, Avda. Camilo Jose Cela, 1, 13071 Ciudad Real (Spain)

    2011-01-15

    The mineralization of solutions containing a mixture of three phenolic compounds, gallic, p-coumaric and protocatechuic acids, in a ferrioxalate-induced solar photo-Fenton process was investigated. The reactions were carried out in a pilot plant consisting of a compound parabolic collector (CPC) solar reactor. An optimization study was performed combining a multivariate experimental design and neuronal networks that included the following variables: pH, temperature, solar power, air flow and initial concentrations of H{sub 2}O{sub 2}, Fe(II) and oxalic acid. Under optimal conditions, total elimination of the original compounds and 94% TOC removal of the mixture were achieved in 5 and 194 min, respectively. pH and initial concentrations of H{sub 2}O{sub 2} and Fe(II) were the most significant factors affecting the mixture mineralization. The molar correlation between consumed hydrogen peroxide and removed TOC was always between 1 and 3. A detailed analysis of the reaction was presented. The values of the pseudo-first-order mineralization kinetic rate constant, k{sub TOC}, increased as initial Fe(II) and H{sub 2}O{sub 2} concentrations and temperature increased. The optimum pH value also slightly increased with greater Fe(II) and hydrogen peroxide concentrations but decreased when temperature increased. {center_dot}OH and O{sub 2}{center_dot}{sup -} radicals were the main oxidative intermediate species in the process, although singlet oxygen ({sup 1}O{sub 2}) also played a role in the mineralization reaction.

  8. Factorial experimental design for the optimization of catalytic degradation of malachite green dye in aqueous solution by Fenton process

    Directory of Open Access Journals (Sweden)

    A. Elhalil

    2016-09-01

    Full Text Available This work focuses on the optimization of the catalytic degradation of malachite green dye (MG by Fenton process “Fe2+/H2O2”. A 24 full factorial experimental design was used to evaluate the effects of four factors considered in the optimization of the oxidative process: concentration of MG (X1, concentration of Fe2+ (X2, concentration of H2O2 (X3 and temperature (X4. Individual and interaction effects of the factors that influenced the percentage of dye degradation were tested. The effect of interactions between the four parameters shows that there is a dependency between concentration of MG and concentration of Fe2+; concentration of Fe2+ and concentration of H2O2, expressed by the great values of the coefficient of interaction. The analysis of variance proved that, the concentration of MG, the concentration of Fe2+ and the concentration of H2O2 have an influence on the catalytic degradation while it is not the case for the temperature. In the optimization, the great dependence between observed and predicted degradation efficiency, the correlation coefficient for the model (R2=0.986 and the important value of F-ratio proved the validity of the model. The optimum degradation efficiency of malachite green was 93.83%, when the operational parameters were malachite green concentration of 10 mg/L, Fe2+ concentration of 10 mM, H2O2 concentration of 25.6 mM and temperature of 40 °C.

  9. Magnetic Fe{sub 2}MO{sub 4} (M:Fe, Mn) activated carbons: Fabrication, characterization and heterogeneous Fenton oxidation of methyl orange

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Thi Dung [Institute of Chemical Technology, Vietnamese Academy of Science and Technology, 01 Mac Dinh Chi, District 1, Ho Chi Minh (Viet Nam); Phan, Ngoc Hoa [Department of Chemical Technology, Hochiminh University of Technology, 268 Ly Thuong Kiet, District 10, Ho Chi Minh (Viet Nam); Do, Manh Huy, E-mail: huydoma@vast-hcm.ac.vn [Institute of Chemical Technology, Vietnamese Academy of Science and Technology, 01 Mac Dinh Chi, District 1, Ho Chi Minh (Viet Nam); Ngo, Kim Tham [Institute of Chemical Technology, Vietnamese Academy of Science and Technology, 01 Mac Dinh Chi, District 1, Ho Chi Minh (Viet Nam); College of science, Can Tho University, 3/2, Can Tho (Viet Nam)

    2011-01-30

    We present a simple and efficient method for the fabrication of magnetic Fe{sub 2}MO{sub 4} (M:Fe and Mn) activated carbons (Fe{sub 2}MO{sub 4}/AC-H, M:Fe and Mn) by impregnating the activated carbon with simultaneous magnetic precursor and carbon modifying agent followed by calcination. The obtained samples were characterized by nitrogen adsorption isotherms, X-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM), and the catalytic activity in heterogeneous Fenton oxidation of methyl orange (MO) was evaluated. The resulting Fe{sub 2}MnO{sub 4}/AC-H showed higher catalytic activity in the methyl orange oxidation than Fe{sub 3}O{sub 4}/AC-H. The effect of operational parameters (pH, catalyst loading H{sub 2}O{sub 2} dosage and initial MO concentration) on degradation performance of the oxidation process was investigated. Stability and reusability of selected catalyst were also tested.

  10. Solar photoassisted advanced oxidation process of azo dyes.

    Science.gov (United States)

    Prato-Garcia, D; Buitrón, G

    2009-01-01

    Advanced oxidation processes assisted with natural solar radiation in CPC type reactors (parabolic collector compound), was applied for the degradation of three azo dyes: acid orange (AO7), acid red 151 (AR151) and acid blue 113 (AB113). Fenton, Fenton like and ferrioxalate-type complexes showed to be effective for degrade the azo linkage and moieties in different extensions. Initially, the best dose of reagents (Fe(3 + )-H(2)O(2)) was determined through a factorial experimental design, next, using response surface methodologies, the reagent consumption was reduced up to 40%, maintaining in all cases high decolourisation percentages (>98%) after 60 min. of phototreatment. In this work, it was also studied the effect of concentration changes of the influent between 100-300 mg/L and the operation of the photocatalytic process near neutral conditions (pH 6.0-6.5) by using ferrioxalate type complex (FeOx).

  11. Reduction of antibiotic resistance genes in municipal wastewater effluent by advanced oxidation processes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yingying; Zhuang, Yao; Geng, Jinju, E-mail: jjgeng@nju.edu.cn; Ren, Hongqiang; Xu, Ke; Ding, Lili

    2016-04-15

    This study investigated the reduction of antibiotic resistance genes (ARGs), intI1 and 16S rRNA genes, by advanced oxidation processes (AOPs), namely Fenton oxidation (Fe{sup 2+}/H{sub 2}O{sub 2}) and UV/H{sub 2}O{sub 2} process. The ARGs include sul1, tetX, and tetG from municipal wastewater effluent. The results indicated that the Fenton oxidation and UV/H{sub 2}O{sub 2} process could reduce selected ARGs effectively. Oxidation by the Fenton process was slightly better than that of the UV/H{sub 2}O{sub 2} method. Particularly, for the Fenton oxidation, under the optimal condition wherein Fe{sup 2+}/H{sub 2}O{sub 2} had a molar ratio of 0.1 and a H{sub 2}O{sub 2} concentration of 0.01 mol L{sup −1} with a pH of 3.0 and reaction time of 2 h, 2.58–3.79 logs of target genes were removed. Under the initial effluent pH condition (pH = 7.0), the removal was 2.26–3.35 logs. For the UV/H{sub 2}O{sub 2} process, when the pH was 3.5 with a H{sub 2}O{sub 2} concentration of 0.01 mol L{sup −1} accompanied by 30 min of UV irradiation, all ARGs could achieve a reduction of 2.8–3.5 logs, and 1.55–2.32 logs at a pH of 7.0. The Fenton oxidation and UV/H{sub 2}O{sub 2} process followed the first-order reaction kinetic model. The removal of target genes was affected by many parameters, including initial Fe{sup 2+}/H{sub 2}O{sub 2} molar ratios, H{sub 2}O{sub 2} concentration, solution pH, and reaction time. Among these factors, reagent concentrations and pH values are the most important factors during AOPs. - Highlights: • AOPs including Fenton oxidation and UV/H{sub 2}O{sub 2} process could reduce ARGs effectively. • Fenton oxidation is slightly more effective than UV/H{sub 2}O{sub 2} process in ARG reduction. • Removal of ARGs by AOPs follows the first-order reaction kinetic model. • Selected ARGs and 16S rRNA genes exhibit similar change trends during AOPs.

  12. Reduction of antibiotic resistance genes in municipal wastewater effluent by advanced oxidation processes

    International Nuclear Information System (INIS)

    Zhang, Yingying; Zhuang, Yao; Geng, Jinju; Ren, Hongqiang; Xu, Ke; Ding, Lili

    2016-01-01

    This study investigated the reduction of antibiotic resistance genes (ARGs), intI1 and 16S rRNA genes, by advanced oxidation processes (AOPs), namely Fenton oxidation (Fe"2"+/H_2O_2) and UV/H_2O_2 process. The ARGs include sul1, tetX, and tetG from municipal wastewater effluent. The results indicated that the Fenton oxidation and UV/H_2O_2 process could reduce selected ARGs effectively. Oxidation by the Fenton process was slightly better than that of the UV/H_2O_2 method. Particularly, for the Fenton oxidation, under the optimal condition wherein Fe"2"+/H_2O_2 had a molar ratio of 0.1 and a H_2O_2 concentration of 0.01 mol L"−"1 with a pH of 3.0 and reaction time of 2 h, 2.58–3.79 logs of target genes were removed. Under the initial effluent pH condition (pH = 7.0), the removal was 2.26–3.35 logs. For the UV/H_2O_2 process, when the pH was 3.5 with a H_2O_2 concentration of 0.01 mol L"−"1 accompanied by 30 min of UV irradiation, all ARGs could achieve a reduction of 2.8–3.5 logs, and 1.55–2.32 logs at a pH of 7.0. The Fenton oxidation and UV/H_2O_2 process followed the first-order reaction kinetic model. The removal of target genes was affected by many parameters, including initial Fe"2"+/H_2O_2 molar ratios, H_2O_2 concentration, solution pH, and reaction time. Among these factors, reagent concentrations and pH values are the most important factors during AOPs. - Highlights: • AOPs including Fenton oxidation and UV/H_2O_2 process could reduce ARGs effectively. • Fenton oxidation is slightly more effective than UV/H_2O_2 process in ARG reduction. • Removal of ARGs by AOPs follows the first-order reaction kinetic model. • Selected ARGs and 16S rRNA genes exhibit similar change trends during AOPs.

  13. Optimizing electrocoagulation and electro-Fenton process for treating car wash wastewater

    Directory of Open Access Journals (Sweden)

    Seyyedali Mirshahghassemi

    2017-02-01

    Full Text Available Background: Car wash wastewater contains several contaminants such as organic matter, oil, grease, detergents and phosphates, all of which are harmful for the environment. In this study, the application of electrocoagulation (EC to treat car wash wastewater has been studied, and the operating parameters optimized. The electro-Fenton (EF for further contaminant removal was also investigated. Methods: In EC process, the effect of pH, current density, and the reaction time of the removal efficiency of chemical oxygen demand (COD, phosphate, and turbidity were investigated using the response surface methodology (RSM. The electrochemical cell consisted of four iron electrodes that were connected to a power supply using a monopolar arrangement. In the EF process, the effect of pH, reaction time, and hydrogen peroxide concentration on COD removal efficiency were probed. Results: The optimum pH, current density, and the reaction time for the EC process were 7.3, 4.2 mA cm-2 and 20.3 minutes, respectively. Under these conditions, the COD, phosphate, and turbidity removal percentages were 80.8%, 94.9% and 85.5%, respectively, and the specific energy consumption was 1.5 kWh m-3. For the EF process, the optimum pH, reaction time, current and hydrogen peroxide dosage were 3, 10 minutes, 2 A and 500 mg L-1, respectively. The EF showed higher COD removal efficiency (85.6% with a lower specific energy consumption (0.5 kWh m-3 and reaction time compared to the EC. Conclusion: This study shows that both EC and EF can effectively treat car wash wastewater with high removal efficiency within a short reaction time.

  14. Application of advanced oxidative process in treatment radioactive waste

    International Nuclear Information System (INIS)

    Kim, Catia; Sakata, Solange K.; Ferreira, Rafael V.P.; Marumo, Julio T.

    2009-01-01

    The ion exchange resin is used in the water purification system in both nuclear research and power reactors. Combined with active carbon, the resin removes dissolved elements from water when the nuclear reactor is operating. After its consumption, it becomes a special type of radioactive waste. The usual treatment to this type of waste is the immobilization with Portland cement, which is simple and low cost. However, its low capacity of immobilization and the increase volume of waste have been the challenges. The development of new technologies capable of destroying this waste completely by increasing its solidification is the main target due to the possibility of both volume and cost reduction. The objective of this work was to evaluate ion exchange resin degradation by Advanced Oxidative Process using Fenton's Reagent (H 2 O 2 / Fe +2 ) in different concentration and temperatures. One advantage of this process is that all additional organic compounds or inorganic solids produced are oxidized easily. The degradation experiments were conducted with IRA-400 resin and Fenton's Reagents, varying the H 2O 2 concentration (30% e 50%) and heat temperature (25, 60 and 100 deg C). The resin degradation was confirmed by the presence of BaCO 3 as a white precipitate resulting from the reaction between the Ba(OH) 2 and the CO 2 from the resin degradation. All experiments run in duplicate. Higher degradation was observed with Fenton's Reagent (Fe +2 /H 2 O 2 30%) at 100 deg C after 2 hours. (author)

  15. Fenton-like Degradation of Phenol Catalyzed by a Series of Fe-Containing Mixed Oxides Systems

    Science.gov (United States)

    Alhmoud, T. T.; Mahmoud, S. S.; Hammoudeh, A. Y.

    2018-02-01

    In our attempts to develop a solid catalyst to degrade organic pollutants in wastewater via the Fenton-like reaction, six Fe-containing mixed oxide systems were prepared by means of the sol-gel auto-combustion method to have the following stoichiometries: CuFe1.2O2.8, BaFe7.2O11.8, BaFe7.2Cu2O13.8, BaFe5.4V3O16.6, BaFe4.8Cu2V3O17.7 and Ag2Fe5.4V3O16.6. The prepared systems were thermally treated at 550°C, 650°C, 800°C and 1100°C, and then characterized by XRD to identify the present phases. The systems were tested with respect to their catalytic efficiency in the degradation of phenol (200 ppm) in water where CuFe1.2O2.8 was found to be the most reactive one (80% removal in 60 min). It showed thereby first-order kinetics and an enhanced behavior under irradiation with a 30-W LED light source. The positive role of irradiation was most obvious in the case of Ag2Fe5.4V3O16.6 in which almost complete conversion was achieved in 120 min compared to only 45% in the same period but without irradiation. However, increasing the temperature at which thermal treatment is performed was found to suppress the catalytic activity of the system. Due to their high efficiency and rather low leaching rates of constituents, CuFe1.2O2.8 or Ag2Fe5.4V3O16.6 seem to be very promising in the Fenton-like degradation of organic pollutants.

  16. Development of a trickle bed reactor of electro-Fenton process for wastewater treatment.

    Science.gov (United States)

    Lei, Yangming; Liu, Hong; Shen, Zhemin; Wang, Wenhua

    2013-10-15

    To avoid electrolyte leakage and gas bubbles in the electro-Fenton (E-Fenton) reactors using a gas diffusion cathode, we developed a trickle bed cathode by coating a layer composed of carbon black and polytetrafluoroethylene (C-PTFE) onto graphite chips instead of carbon cloth. The trickle bed cathode was optimized by single-factor and orthogonal experiments, in which carbon black, PTFE, and a surfactant were considered as the determinant of the performance of graphite chips. In the reactor assembled by the trickle bed cathode, H2O2 was generated with a current of 0.3A and a current efficiency of 60%. This performance was attributed to the fine distribution of electrolyte and air, as well as the effective oxygen transfer from the gas phase to the electrolyte-cathode interface. In terms of H2O2 generation and current efficiency, the developed trickle bed reactor had a performance comparable to that of the conventional E-Fenton reactor using a gas diffusion cathode. Further, 123 mg L(-1) of reactive brilliant red X-3B in aqueous solution was decomposed in the optimized trickle bed reactor as E-Fenton reactor. The decolorization ratio reached 97% within 20 min, and the mineralization reached 87% within 3h. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Analogies and differences among bacterial and viral disinfection by the photo-Fenton process at neutral pH: a mini review.

    Science.gov (United States)

    Giannakis, Stefanos

    2017-12-19

    Over the last years, the photo-Fenton process has been established as an effective, green alternative to chemical disinfection of waters and wastewaters. Microorganisms' inactivation is the latest success story in the application of this process at near-neutral pH, albeit without clearly elucidated inactivation mechanisms. In this review, the main pathways of the combined photo-Fenton process against the most frequent pathogen models (Escherichia coli for bacteria and MS2 bacteriophage for viruses) are analyzed. Firstly, the action of solar light is described and the specific inactivation mechanisms in bacteria (internal photo-Fenton) and viruses (genome damage) are presented. The contribution of the external pathways due to the potential presence of organic matter in generating reactive oxygen species (ROS) and their effects on microorganism inactivation are discussed. Afterwards, the effects of the gradual addition of Fe and H 2 O 2 are assessed and the differences among bacterial and viral inactivation are highlighted. As a final step, the simultaneous addition of both reagents induces the photo-Fenton in the bulk, focusing on the differences induced by the homogeneous or heterogeneous fraction of the process and the variation among the two respective targets. This work exploits the accumulated evidence on the mechanisms of bacterial inactivation and the scarce ones towards viral targets, aiming to bridge this knowledge gap and make possible the further application of the photo-Fenton process in the field of water/wastewater treatment.

  18. Treatment of azo dye-containing wastewater by a Fenton-like process in a continuous packed-bed reactor filled with activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Mesquita, Isabel; Matos, Luis C. [Chemical Engineering Department, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Duarte, Filipa [Chemical Engineering Department, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); LEPAE - Laboratory for Process, Environmental and Energy Engineering, Department of Chemical Engineering, Faculty of Engineering, University of Porto, Porto (Portugal); Maldonado-Hodar, F.J. [Department of Inorganic Chemistry, Faculty of Sciences, University of Granada, Av. Fuentenueva, 18071 Granada (Spain); Mendes, Adelio [Chemical Engineering Department, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); LEPAE - Laboratory for Process, Environmental and Energy Engineering, Department of Chemical Engineering, Faculty of Engineering, University of Porto, Porto (Portugal); Madeira, Luis M., E-mail: mmadeira@fe.up.pt [Chemical Engineering Department, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); LEPAE - Laboratory for Process, Environmental and Energy Engineering, Department of Chemical Engineering, Faculty of Engineering, University of Porto, Porto (Portugal)

    2012-10-30

    Highlights: Black-Right-Pointing-Pointer Oxidation with the Fenton's reagent was carried out in a packed-bed reactor. Black-Right-Pointing-Pointer The packed-bed was filled with iron-impregnated activated carbon. Black-Right-Pointing-Pointer The increment of temperature increases the Chicago Sky Blue removal and mineralization. Black-Right-Pointing-Pointer The values of iron leaching were below 0.4 ppm in the outlet effluent. Black-Right-Pointing-Pointer It was possible to reach a dye conversion of 88% in steady-state. - Abstract: In this work, oxidation with a Fenton-like process of a dye solution was carried out in a packed-bed reactor. Activated carbon Norit RX 3 Extra was impregnated with ferrous sulfate and used as catalyst (7 wt.% of iron). The effect of the main operating conditions in the Chicago Sky Blue (CSB) degradation was analyzed. It was found that the increase in temperature leads to a higher removal of the dye and an increased mineralization. However, it also increases the iron leaching, but the values observed were below 0.4 ppm (thus, far below European Union limits). It was possible to reach, at steady-state, a dye conversion of 88%, with a total organic carbon (TOC) removal of ca. 47%, being the reactor operated at 50 Degree-Sign C, pH 3, W{sub cat}/Q = 4.1 g min mL{sup -1} (W{sub cat} is the mass of catalyst and Q the total feed flow rate) and a H{sub 2}O{sub 2} feed concentration of 2.25 mM (for a CSB feed concentration of 0.012 mM). The same performance was reached in three consecutive cycles.

  19. Degradation of p-nitrophenol using acoustic cavitation and Fenton chemistry

    International Nuclear Information System (INIS)

    Pradhan, Amey A.; Gogate, Parag R.

    2010-01-01

    Due to increasing human requirements, newer chemical species are being observed in the effluent streams with higher loadings such that efficacy of conventional treatment techniques is decreased and a combination of advanced oxidation processes is implemented for enhanced treatment ability and better energy efficiency. In the present work, the efficacy of combination of sonochemistry and Fenton chemistry has been investigated for wastewater treatment considering p-nitrophenol as model pollutant at pilot scale operation. Degradation of p-nitrophenol has been investigated under various operating conditions based on the use of ultrasound, Fenton process, ultrasound and H 2 O 2 , ultrasound and Fe, ultrasound and FeSO 4 , ultrasound and conventional Fenton process and ultrasound and advanced Fenton process. Two different initial concentrations of 0.5 and 1% of p-nitrophenol have been used for the experiments. In conventional Fenton and advanced Fenton process, two loadings of FeSO 4 and Fe powder 0.5 and 1 g/l and three ratios of FeSO 4 :H 2 O 2 and Fe:H 2 O 2 (1:5, 1:7.5 and 1:10) were investigated respectively. In all the systems investigated, maximum extent of degradation (66.4%) was observed for 0.5% p-nitrophenol concentration (w/v) using a combination of ultrasound and advanced Fenton process. The novelty of the work is in terms of investigating the efficacies of combined advanced oxidation processes based on the use of cavitation and Fenton chemistry at pilot scale operation and tries to establish the missing design related information for large scale operation of wastewater treatment.

  20. Preparation of natural pyrite nanoparticles by high energy planetary ball milling as a nanocatalyst for heterogeneous Fenton process

    Energy Technology Data Exchange (ETDEWEB)

    Fathinia, Siavash [Department of Mining Engineering, Faculty of Engineering and Technology, Imam Khomeini International University, Qazvin (Iran, Islamic Republic of); Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Fathinia, Mehrangiz [Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of); Rahmani, Ali Akbar [Department of Mining Engineering, Faculty of Engineering and Technology, Imam Khomeini International University, Qazvin (Iran, Islamic Republic of); Khataee, Alireza, E-mail: a_khataee@tabrizu.ac.ir [Research Laboratory of Advanced Water and Wastewater Treatment Processes, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2015-02-01

    Graphical abstract: - Highlights: • Pyrite nanoparticles were successfully produced by planetary ball milling process. • The physical and chemical properties of pyrite nanoparticles were fully examined. • The degradation of AO7 was notably enhanced by pyrite nanoparticles Fenton system. • The influences of basic operational parameters were investigated using CCD. - Abstract: In the present study pyrite nanoparticles were prepared by high energy mechanical ball milling utilizing a planetary ball mill. Various pyrite samples were produced by changing the milling time from 2 h to 6 h, in the constant milling speed of 320 rpm. X-ray diffraction (XRD), scanning electron microscopy (SEM) linked with energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR) analysis and Brunauer–Emmett–Teller (BET) were performed to explain the characteristics of primary (unmilled) and milled pyrite samples. The average particle size distribution of the produced pyrite during 6 h milling was found to be between 20 nm and 100 nm. The catalytic performance of the different pyrite samples was examined in the heterogeneous Fenton process for degradation of C.I. Acid Orange 7 (AO7) solution. Results showed that the decolorization efficiency of AO7 in the presence of 6 h-milled pyrite sample was the highest. The impact of key parameters on the degradation efficiency of AO7 by pyrite nanoparticles catalyzed Fenton process was modeled using central composite design (CCD). Accordingly, the maximum removal efficiency of 96.30% was achieved at initial AO7 concentration of 16 mg/L, H{sub 2}O{sub 2} concentration of 5 mmol/L, catalyst amount of 0.5 g/L and reaction time of 25 min.

  1. Environmental sustainability of the solar photo-Fenton process for wastewater treatment and pharmaceuticals mineralization at semi-industrial scale.

    Science.gov (United States)

    Foteinis, Spyros; Monteagudo, Jose Maria; Durán, Antonio; Chatzisymeon, Efthalia

    2018-01-15

    The environmental sustainability of a semi-industrial solar photo-Fenton reactor, treating real effluents emanating from a pharmaceutical laboratory, is assessed herein. The life cycle assessment/analysis (LCA) methodology was employed and real life cycle inventory (LCI) data was collected from a ferrioxalate-assisted homogeneous solar photo-Fenton wastewater treatment plant (WWTP), at Ciudad Real, Spain. Electricity was provided by photovoltaic (PV) panels in tandem with a battery bank, making the plant autonomous from the local grid. The effective treatment of 1m 3 of secondary-treated pharmaceutical wastewater, containing antipyrine, was used as a functional unit. The main environmental hotspot was identified to be the chemical reagents used to enhance treatment efficiency, mainly hydrogen peroxide (H 2 O 2 ) and to a smaller degree oxalic acid. On the other hand, land use, PV panels, battery units, compound parabolic collectors (CPC), tanks, pipes and pumps, as materials, had a low contribution, ranging from as little as 0.06% up to about 2% on the total CO 2eq emissions. Overall, the solar photo-Fenton process was found to be a sustainable technology for treating wastewater containing micropollutants at semi-industrial level, since the total environmental footprint was found to be 2.71kgCO 2 m -3 or 272mPtm -3 , using IPCC 2013 and ReCiPe impact assessment methods, respectively. A sensitivity analysis revealed that if the excess of solar power is fed back into the grid then the total environmental footprint is reduced. Depending on the amount of solar power fed back into the grid the process could have a near zero total environmental footprint. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Notable light-free catalytic activity for pollutant destruction over flower-like BiOI microspheres by a dual-reaction-center Fenton-like process.

    Science.gov (United States)

    Wang, Liang; Yan, Dengbiao; Lyu, Lai; Hu, Chun; Jiang, Ning; Zhang, Lili

    2018-10-01

    BiOI is widely used as photocatalysts for pollutant removal, water splitting, CO 2 reduction and organic transformation due to its excellent photoelectric properties. Here, we report for the first time that a light-free catalyst consisting of the flower-like BiOI microspheres (f-BiOI MSs) exposing (1 0 1) and (1 1 0) crystal planes prepared by a hydrothermal method in ethylene glycol environment can rapidly eliminate the refractory BPA within only ∼3 min through a Fenton-like process. The reaction activity is ∼190 times higher than that of the conventional Fenton catalyst Fe 2 O 3 . A series of characterizations and experiments reveal the formation of the dual reaction centers on f-BiOI MSs. The electron-rich O centers efficiently reduce H 2 O 2 to OH, while the electron-poor oxygen vacancies capture electrons from the adsorbed pollutants and divert them to the electron-rich area during the Fenton-like reactions. By these processes, pollutants are degraded and mineralized quickly in a wide pH range. Our findings address the problems of the classical Fenton reaction and are useful for the development of efficient Fenton-like catalysts through constructing dual reaction centers. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. Nanocasted synthesis of magnetic mesoporous iron cerium bimetal oxides (MMIC) as an efficient heterogeneous Fenton-like catalyst for oxidation of arsenite.

    Science.gov (United States)

    Wen, Zhipan; Zhang, Yalei; Dai, Chaomeng; Sun, Zhen

    2015-04-28

    Magnetic mesoporous iron cerium bimetal oxides (MMIC) with large surface area and pore volume was synthesized via the hard template approach. This obtained MMIC was easily separated from aqueous solution with an external magnetic field and was proposed as a heterogeneous Fenton-like catalyst for oxidation of As(III). The MMIC presented excellent catalytic activity for the oxidation of As(III), achieving almost complete oxidation of 1000ppb As(III) after 60min and complete removal of arsenic species after 180min with reaction conditions of 0.4g/L catalyst, pH of 3.0 and 0.4mM H2O2. Kinetics analysis showed that arsenic removal followed the pseudo-first order, and the pseudo-first-order rate constants increased from 0.0014min(-1) to 0.0548min(-1) as the H2O2 concentration increased from 0.04mM to 0.4mM. On the basis of the effects of XPS analysis and reactive oxidizing species, As(III) in aqueous solution was mainly oxidized by OH radicals, including the surface-bound OHads generated on the MMIC surface which were involved in Fe(2+) and Ce(3+), and free OHfree generation by soluble iron ions which were released from the MMIC into the bulk solution, and the generated As(V) was finally removed by MMIC through adsorption. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Treatment of laundrette wastewater using Starbon and Fenton's reagent.

    Science.gov (United States)

    Tony, Maha A; Parker, Helen L; Clark, James H

    2016-09-18

    The use of grey water for a variety of purposes is gaining increased popularity as a means of preserving scarce freshwater resources. In this work, catalytic oxidation over Fenton's reagent and adsorption techniques using Starbon (mesoporous material derived from polysaccharides) has been applied. These novel techniques are used as an alternative to already studied treatments of grey water such as filtration and/or biological processes. In this study, grey water, collected from a commercial laundrette, has been used. Treatment efficiency was determined by changes in the chemical oxygen demand (COD) of the grey water. Experiments using Fenton's reagent at optimum conditions of Fe(3+) = 40 mg L(-1); H2O2 = 400 mg L(-1) and pH 3 were very successful, resulting in a 95% COD removal after 15 min. Treatment with Starbon adsorption was also effective, reaching up to 81% COD removal at pH 3 within 1 h. The combined treatment with Fenton's reagent and Starbon resulted in a 93% COD removal at a significantly reduced concentration of Fenton's reagent compared to the treatment with solo Fenton's reagent. This lower chemical dose has the advantage of reducing costs and lowering sludge generation.

  5. Electrochemical advanced oxidation processes: today and tomorrow. A review.

    Science.gov (United States)

    Sirés, Ignasi; Brillas, Enric; Oturan, Mehmet A; Rodrigo, Manuel A; Panizza, Marco

    2014-01-01

    In recent years, new advanced oxidation processes based on the electrochemical technology, the so-called electrochemical advanced oxidation processes (EAOPs), have been developed for the prevention and remediation of environmental pollution, especially focusing on water streams. These methods are based on the electrochemical generation of a very powerful oxidizing agent, such as the hydroxyl radical ((•)OH) in solution, which is then able to destroy organics up to their mineralization. EAOPs include heterogeneous processes like anodic oxidation and photoelectrocatalysis methods, in which (•)OH are generated at the anode surface either electrochemically or photochemically, and homogeneous processes like electro-Fenton, photoelectro-Fenton, and sonoelectrolysis, in which (•)OH are produced in the bulk solution. This paper presents a general overview of the application of EAOPs on the removal of aqueous organic pollutants, first reviewing the most recent works and then looking to the future. A global perspective on the fundamentals and experimental setups is offered, and laboratory-scale and pilot-scale experiments are examined and discussed.

  6. Degradation of 2,4-dinitrophenol using a combination of hydrodynamic cavitation, chemical and advanced oxidation processes.

    Science.gov (United States)

    Bagal, Manisha V; Gogate, Parag R

    2013-09-01

    In the present work, degradation of 2,4-dinitrophenol (DNP), a persistent organic contaminant with high toxicity and very low biodegradability has been investigated using combination of hydrodynamic cavitation (HC) and chemical/advanced oxidation. The cavitating conditions have been generated using orifice plate as a cavitating device. Initially, the optimization of basic operating parameters have been done by performing experiments over varying inlet pressure (over the range of 3-6 bar), temperature (30 °C, 35 °C and 40 °C) and solution pH (over the range of 3-11). Subsequently, combined treatment strategies have been investigated for process intensification of the degradation process. The effect of HC combined with chemical oxidation processes such as hydrogen peroxide (HC/H2O2), ferrous activated persulfate (HC/Na2S2O8/FeSO4) and HC coupled with advanced oxidation processes such as conventional Fenton (HC/FeSO4/H2O2), advanced Fenton (HC/Fe/H2O2) and Fenton-like process (HC/CuO/H2O2) on the extent of degradation of DNP have also been investigated at optimized conditions of pH 4, temperature of 35 °C and inlet pressure of 4 bar. Kinetic study revealed that degradation of DNP fitted first order kinetics for all the approaches under investigation. Complete degradation with maximum rate of DNP degradation has been observed for the combined HC/Fenton process. The energy consumption analysis for hydrodynamic cavitation based process has been done on the basis of cavitational yield. Degradation intermediates have also been identified and quantified in the current work. The synergistic index calculated for all the combined processes indicates HC/Fenton process is more feasible than the combination of HC with other Fenton like processes. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Insights into solar photo-Fenton reaction parameters in the oxidation of a sanitary landfill leachate at lab-scale.

    Science.gov (United States)

    Silva, Tânia F C V; Ferreira, Rui; Soares, Petrick A; Manenti, Diego R; Fonseca, Amélia; Saraiva, Isabel; Boaventura, Rui A R; Vilar, Vítor J P

    2015-12-01

    This work evaluates the effect of the main photo-Fenton (PF) reaction variables on the treatment of a sanitary landfill leachate collected at the outlet of a leachate treatment plant, which includes aerated lagooning followed by aerated activated sludge and a final coagulation-flocculation step. The PF experiments were performed in a lab-scale compound parabolic collector (CPC) photoreactor using artificial solar radiation. The photocatalytic reaction rate was determined while varying the total dissolved iron concentration (20-100 mg Fe(2+)/L), solution pH (2.0-3.6), operating temperature (10-50 °C), type of acid used for acidification (H2SO4, HCl and H2SO4 + HCl) and UV irradiance (22-68 W/m(2)). This work also tries to elucidate the role of ferric hydroxides, ferric sulphate and ferric chloride species, by taking advantage of ferric speciation diagrams, in the efficiency of the PF reaction when applied to leachate oxidation. The molar fraction of the most photoactive ferric species, FeOH(2+), was linearly correlated with the PF pseudo-first order kinetic constants obtained at different solution pH and temperature values. Ferric ion speciation diagrams also showed that the presence of high amounts of chloride ions negatively affected the PF reaction, due to the decrease of ferric ions solubility and scavenging of hydroxyl radicals for chlorine radical formation. The increment of the PF reaction rates with temperature was mainly associated with the increase of the molar fraction of FeOH(2+). The optimal parameters for the photo-Fenton reaction were: pH = 2.8 (acidification agent: H2SO4); T = 30 °C; [Fe(2+)] = 60 mg/L and UV irradiance = 44 WUV/m(2), achieving 72% mineralization after 25 kJUV/L of accumulated UV energy and 149 mM of H2O2 consumed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Landfill Leachate Treatment Using Coupled, Sequential Coagulation-flocculation and Advanced Oxidation Processes

    Directory of Open Access Journals (Sweden)

    José L. Álvarez Cruz

    2017-11-01

    Full Text Available This study evaluated the efficiency of Fenton (Fe/H2O2 and photo-assisted Fenton (Fe2+/H2O2/UV reactions combined with coagulation-flocculation (C-F processes to remove the chemical oxygen demand (COD in a landfill leachate from Mexico at a laboratory scale. The C-F experiments were carried out in jar test equipment using different FeSO4 concentrations (0.0, 0.6, 1.0, 3, and 6 mM at pH = 3.0. The effluent from the C-F processes were then treated using the Fenton reaction. The experiments were carried out in a 500 mL glass reactor fillet with 250 mL of landfill leachate. Different molar ratio concentrations (Fe/H2O2 were tested (e.g., 1.6, 3.3, 30, 40 and 75, and the reaction was followed until COD analysis showed no significant further variation in concentration or until 90 min of reaction time were completed. The photo-assisted Fenton reaction was carried out using a UV lamp (365 nm, 5 mW with the same Fe/H2O2 molar ratio values described above. The results suggested that the photo-assisted Fenton process is the most efficient oxidation method for removing organic matter and color in the leachate. The photo-assisted Fenton process removed 68% of the COD and 90% of the color at pH = 3 over 30 minutes of reaction time using a H2O2/Fe molar ratio equal to 75 only using a third of the reaction time of the previous process.

  9. Enhancement of Fenton processes at initial circumneutral pH for the degradation of norfloxacin with Fe@Fe2O3 core-shell nanomaterials.

    Science.gov (United States)

    Liu, Jingyi; Hu, Wenyong; Sun, Maogui; Xiong, Ouyang; Yu, Haibin; Feng, Haopeng; Wu, Xuan; Tang, Lin; Zhou, Yaoyu

    2018-06-13

    The degradation of norfloxacin by Fenton reagent with core-shell Fe@Fe 2 O 3 nanomaterials was studied under neutral conditions in a closed batch system. Norfloxacin was significantly degraded (90%) in the Fenton system with Fe@Fe 2 O 3 in 30 min at the initial pH 7.0, but slightly degraded in Fenton system without Fe@Fe 2 O 3 under the same experimental conditions. The intermediate products were investigated by gas chromatography-mass spectrometry, and the possible Fenton oxidation pathway of norfloxacin in the presence of Fe@Fe 2 O 3 nanowires was proposed. Electron spin resonance spectroscopy was used to identify and characterize the free radicals generated, and the mechanism for norfloxacin degradation was also revealed. Finally, the reusability and the stability of Fe@Fe 2 O 3 nanomaterials were studied using x-ray diffraction and scanning electron microscope, which indicated that Fe@Fe 2 O 3 is a stable catalyst and can be used repetitively in environmental pollution control.

  10. Characterization of changes in floc morphology, extracellular polymeric substances and heavy metals speciation of anaerobically digested biosolid under treatment with a novel chelated-Fe2+ catalyzed Fenton process.

    Science.gov (United States)

    He, Juanjuan; Yang, Peng; Zhang, Weijun; Cao, Bingdi; Xia, Hua; Luo, Xi; Wang, Dongsheng

    2017-11-01

    A novel chelated-Fe 2+ catalyzed Fenton process (CCFP) was developed to enhance dewatering performance of anaerobically digested biosolid, and changes in floc morphology, extracellular polymeric substances (EPS) and heavy metals speciation were also investigated. The results showed that addition of chelating agents caused EPS solubilization by binding multivalent cations. Like traditional Fenton, CCFP performed well in improving anaerobically digested sludge dewatering property. The highly active radicals (OH, O 2 - ) produced in classical Fenton and CCFP were responsible for sludge flocs destruction and consequently degradation of biopolymers into small molecules. Furthermore, more plentiful pores and channels were presented in cake after Fenton treatment, which was conducive to water drainage under mechanical compression. Additionally, a portion of active heavy metals in the form of oxidizable and reducible states were dissolved under CCFP. Therefore, CCFP could greatly simplify the operating procedure of Fenton conditioning and improve its process adaptability for harmless treatment of biological sludge. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. The role of iron species on the turbidity of oxidized phenol solutions in a photo-Fenton system.

    Science.gov (United States)

    Villota, Natalia; Camarero, Luis M; Lomas, Jose M; Perez-Arce, Jonatan

    2015-01-01

    This work aims at establishing the contribution of the iron species to the turbidity of phenol solutions oxidized with photo-Fenton technology. During oxidation, turbidity increases linearly with time till a maximum value, according to a formation rate that shows a dependence of second order with respect to the catalyst concentration. Next, the decrease in turbidity shows the evolution of second-order kinetics, where the kinetics constant is inversely proportional to the dosage of iron, of order 0.7. The concentration of iron species is analysed at the point of maximum turbidity, as a function of the total amount of iron. Then, it is found that using dosages FeT=0-15.0 mg/L, the majority iron species was found to be ferrous ions, indicating that its concentration increases linearly with the dosage of total iron. This result may indicate that the photo-reaction of ferric ion occurs leading to the regeneration of ferrous ion. The results, obtained by operating with initial dosages FeT=15.0 and 25.0 mg/L, suggest that ferrous ion concentration decreases while ferric ion concentration increases in a complementary manner. This fact could be explained as a regeneration cycle of the iron species. The observed turbidity is generated due to the iron being added as a catalyst and the organic matter present in the system. Later, it was found that at the point of maximum turbidity, the concentration of ferrous ions is inversely proportional to the concentration of phenol and its dihydroxylated intermediates.

  12. Environmental application of millimetre-scale sponge iron (s-Fe{sup 0}) particles (IV): New insights into visible light photo-Fenton-like process with optimum dosage of H{sub 2}O{sub 2} and RhB photosensitizers

    Energy Technology Data Exchange (ETDEWEB)

    Ju, Yongming, E-mail: juyongming@scies.org [South China Institute of Environmental Sciences, Ministry of Environmental Protection (MEP), Guangzhou 510655 (China); Innovative Laboratory for Environmental Functional Materials and Environmental Applications of Microwave Irradiation, South China Subcenter of State Environmental Dioxin Monitoring Center, Guangzhou 510655 (China); Guangdong Key Laboratory of Agro-Environment Integrated Control, South China Institute of Environmental Sciences, Guangzhou 510655 (China); Yu, Yunjiang, E-mail: yuyunjiang@scies.org [South China Institute of Environmental Sciences, Ministry of Environmental Protection (MEP), Guangzhou 510655 (China); Wang, Xiaoyan; Xiang, Mingdeng; Li, Liangzhong [South China Institute of Environmental Sciences, Ministry of Environmental Protection (MEP), Guangzhou 510655 (China); Deng, Dongyang [South China Institute of Environmental Sciences, Ministry of Environmental Protection (MEP), Guangzhou 510655 (China); Innovative Laboratory for Environmental Functional Materials and Environmental Applications of Microwave Irradiation, South China Subcenter of State Environmental Dioxin Monitoring Center, Guangzhou 510655 (China); Guangdong Key Laboratory of Agro-Environment Integrated Control, South China Institute of Environmental Sciences, Guangzhou 510655 (China); Dionysiou, Dionysios D., E-mail: dionysios.d.dionysiou@uc.edu [Environmental Engineering and Science Program, Department of Biomedical, Chemical and Environmental Engineering (DBCEE), University of Cincinnati, Cincinnati, Ohio, 45221-0012 (United States)

    2017-02-05

    Highlights: • Synergistic action of Rhodamine B (RhB), visible light, H{sub 2}O{sub 2} and s-Fe{sup 0} is essential. • The complexes of RhB and Fe{sup 3+} eject one electron via ligand-to-metal charge-transfer. • RhB assists the photo-Fenton-like removal of tetrabromobisphenol A (TBBPA). - Abstract: In this study, we firstly develop the photo-Fenton-like system with millimetric sponge iron (s-Fe{sup 0}), H{sub 2}O{sub 2}, visible light (vis, λ ≥ 420 nm) and rhodamine B (RhB), and present a comprehensive study concerning the mechanism. Thus, we investigate (1) the adsorption of RhB onto s-Fe{sup 0}, (2) the photo-Fenton-like removal of RhB over iron oxides generated from the corrosion of s-Fe{sup 0}, (3) the homogeneous photo-Fenton removal of RhB over Fe{sup 2+} or Fe{sup 3+}, (4) the Fe{sup 3+}-RhB complexes, and (5) the photo-Fenton-like removal of tetrabromobisphenol A (TBBPA). The results show that neither the adsorption process over s-Fe{sup 0} nor the photo-Fenton-like process over FeOOH, Fe{sub 3}O{sub 4} and Fe{sub 2}O{sub 3}, achieved efficient removal of RhB. For comparison, in homogeneous photo-Fenton process, the presence of Fe{sup 3+} ions, rather than Fe{sup 2+} ions, effectively eliminated RhB. Furthermore, the UV–vis spectra showing new absorbance at ∼ 285 nm indicate the complexes of RhB and Fe{sup 3+} ions, adopting vis photons to form excited state and further eject one electron via ligand-to-metal charge-transfer to activate H{sub 2}O{sub 2}. Additionally, efficient TBBPA removal was obtained only in the presence of RhB. Accordingly, the s-Fe{sup 0}– based photo-Fenton-like process assisted with dyestuff wastewater is promising for removing a series of persistent organic pollutants.

  13. Electro-Fenton, UVA photoelectro-Fenton and solar photoelectro-Fenton degradation of the drug ibuprofen in acid aqueous medium using platinum and boron-doped diamond anodes

    Energy Technology Data Exchange (ETDEWEB)

    Skoumal, Marcel; Rodriguez, Rosa Maria; Cabot, Pere Lluis; Centellas, Francesc; Garrido, Jose Antonio; Arias, Conchita [Laboratori d' Electroquimica dels Materials i del Medi Ambient, Departament de Quimica Fisica, Facultat de Quimica, Universitat de Barcelona, Marti i Franques 1-11, 08028 Barcelona (Spain); Brillas, Enric [Laboratori d' Electroquimica dels Materials i del Medi Ambient, Departament de Quimica Fisica, Facultat de Quimica, Universitat de Barcelona, Marti i Franques 1-11, 08028 Barcelona (Spain)], E-mail: brillas@ub.edu

    2009-02-28

    The degradation of a 41 mg dm{sup -3} ibuprofen (2-(4-isobutylphenyl)propionic acid) solution of pH 3.0 has been comparatively studied by electrochemical advanced oxidation processes (EAOPs) like electro-Fenton, UVA photoelectro-Fenton and solar photoelectro-Fenton at constant current density. Experiments were performed in a one-compartment cell with a Pt or boron-doped diamond (BDD) anode and an O{sub 2}-diffusion cathode. Heterogeneous hydroxyl radical ({center_dot}OH) is generated at the anode surface from water oxidation, while homogeneous {center_dot}OH is formed from Fenton's reaction between Fe{sup 2+} and H{sub 2}O{sub 2} generated at the cathode, being its production strongly enhanced from photo-Fenton reaction induced by sunlight. Higher mineralization is attained in all methods using BDD instead Pt, because the former produces greater quantity of {center_dot}OH enhancing the oxidation of pollutants. The mineralization rate increases under UVA and solar irradiation by the rapid photodecomposition of complexes of Fe(III) with acidic intermediates. The most potent method is solar photoelectro-Fenton with BDD giving 92% mineralization due to the formation of a small proportion of highly persistent final by-products. The effect of Fe{sup 2+} content, pH and current density on photoelectro-Fenton degradation has been studied. The ibuprofen decay always follows a pseudo-first-order kinetics and its destruction rate is limited by current density and UV intensity. Aromatics such as 1-(1-hydroxyethyl)-4-isobutylbenzene, 4-isobutylacetophenone, 4-isobutylphenol and 4-ethylbenzaldehyde, and carboxylic acids such as pyruvic, acetic, formic and oxalic have been identified as oxidation by-products. Oxalic acid is the ultimate by-product and the fast photodecarboxylation of its complexes with Fe(III) under UVA or solar irradiation explains the higher oxidation power of photoelectro-Fenton methods in comparison to electro-Fenton procedures.

  14. Wastewater treatment using hybrid treatment schemes based on cavitation and Fenton chemistry: a review.

    Science.gov (United States)

    Bagal, Manisha V; Gogate, Parag R

    2014-01-01

    Advanced oxidation processes such as cavitation and Fenton chemistry have shown considerable promise for wastewater treatment applications due to the ease of operation and simple reactor design. In this review, hybrid methods based on cavitation coupled with Fenton process for the treatment of wastewater have been discussed. The basics of individual processes (Acoustic cavitation, Hydrodynamic cavitation, Fenton chemistry) have been discussed initially highlighting the need for combined processes. The different types of reactors used for the combined processes have been discussed with some recommendations for large scale operation. The effects of important operating parameters such as solution temperature, initial pH, initial pollutant concentration and Fenton's reagent dosage have been discussed with guidelines for selection of optimum parameters. The optimization of power density is necessary for ultrasonic processes (US) and combined processes (US/Fenton) whereas the inlet pressure needs to be optimized in the case of Hydrodynamic cavitation (HC) based processes. An overview of different pollutants degraded under optimized conditions using HC/Fenton and US/Fenton process with comparison with individual processes have been presented. It has been observed that the main mechanism for the synergy of the combined process depends on the generation of additional hydroxyl radicals and its proper utilization for the degradation of the pollutant, which is strongly dependent on the loading of hydrogen peroxide. Overall, efficient wastewater treatment with high degree of energy efficiency can be achieved using combined process operating under optimized conditions, as compared to the individual process. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Cold Incineration of Chlorophenols in Aqueous Solution by Advanced Electrochemical Process Electro-Fenton. Effect of Number and Position of Chlorine Atoms on the Degradation Kinetics

    Science.gov (United States)

    Oturan, Nihal; Panizza, Marco; Oturan, Mehmet A.

    2009-09-01

    This study reports the kinetics of the degradation of several chlorophenols (CPs), such as monochlorophenols (2-chlorophenol and 4-chlorophenol), dichlorophenols (2,4-dichlorophenol and 2,6- dichlorophenol), trichlorophenols (2,3,5- trichlorophenol and 2,4,5-trichlorophenol), 2,3,5,6-tetrachlorophenol, and pentachlorophenol, by the electro-Fenton process using a carbon felt cathode and a Pt anode. The effect of number and the position of the chlorine atoms in the aromatic ring on the oxidative degradation rate was evaluated and discussed. The oxidation reaction of all the CPs with hydroxyl radicals evidenced a pseudo-first-order kinetics and the rate constant decreased with increasing the number of chlorine atoms. The absolute rate constant of second-order reaction kinetics between CPs and •OH was determined by the competition kinetics method in the range of (3.56-7.75) × 109 M-1 s-1 and follows the same sequence of the apparent rate constants. The mineralization of several CPs and of a mixture of all CPs under study was monitored by the total organic carbon (TOC) removal and the chlorine release during mineralization was followed by ion chromatography. Our results demonstrated that more chlorinated phenols are more difficult to mineralize; however for all the tested CPs, almost quantitative release of chloride ions was obtained after 6 h of treatment.

  16. Degradation of ethylparaben under simulated sunlight using photo-Fenton.

    Science.gov (United States)

    Zúñiga-Benítez, Henry; Peñuela, Gustavo A

    2016-01-01

    Ethylparaben (EPB) has been classified by different research groups as a potential endocrine-disrupting chemical, implying that it can potentially interfere with the normal balance of the endocrine system of living beings, which with its presence in different effluents, including drinking water, generates the need to seek methods that allow its removal from different water bodies. Advanced oxidation processes have been employed widely to remove organic compounds from different matrices. In this way, Fenton technology (process based on the reaction between ferrous ions and hydrogen peroxide) has been able to degrade different substrates, but due to the Fe(2+) requirements to carry out the reaction optimally, combination of the conventional Fenton process with visible light radiation (photo-Fenton) is an alternative used in the treatment of pollution due to the presence of chemicals. In this way, the effectiveness of photo-Fenton on EPB degradation was assessed using a face-centered central composite experimental design that allowed assessment of the effects of Fe(2+) and H2O2 initial concentrations on process. In general, results indicated that after 180 min of reaction almost all EPB was eliminated, the dissolved organic carbon in solution was reduced and the sample biodegradability index was increased.

  17. Decontamination of soil washing wastewater using solar driven advanced oxidation processes.

    Science.gov (United States)

    Bandala, Erick R; Velasco, Yuridia; Torres, Luis G

    2008-12-30

    Decontamination of soil washing wastewater was performed using two different solar driven advanced oxidation processes (AOPs): the photo-Fenton reaction and the cobalt/peroxymonosulfate/ultraviolet (Co/PMS/UV) process. Complete sodium dodecyl sulphate (SDS), the surfactant agent used to enhance soil washing process, degradation was achieved when the Co/PMS/UV process was used. In the case of photo-Fenton reaction, almost complete SDS degradation was achieved after the use of almost four times the actual energy amount required by the Co/PMS/UV process. Initial reaction rate in the first 15min (IR15) was determined for each process in order to compare them. Highest IR15 value was determined for the Co/PMS/UV process (0.011mmol/min) followed by the photo-Fenton reaction (0.0072mmol/min) and the dark Co/PMS and Fenton processes (IR15=0.002mmol/min in both cases). Organic matter depletion in the wastewater, as the sum of surfactant and total petroleum hydrocarbons present (measured as chemical oxygen demand, COD), was also determined for both solar driven processes. It was found that, for the case of COD, the highest removal (69%) was achieved when photo-Fenton reaction was used whereas Co/PMS/UV process yielded a slightly lower removal (51%). In both cases, organic matter removal achieved was over 50%, which can be consider proper for the coupling of the tested AOPs with conventional wastewater treatment processes such as biodegradation.

  18. Iron modified bentonite: Enhanced adsorption performance for organic pollutant and its regeneration by heterogeneous visible light photo-Fenton process at circumneutral pH

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Yaowen; Guo, Yongzhao; Zhang, Hui, E-mail: eeng@whu.edu.cn

    2016-01-25

    Highlights: • The iron modification markedly improved the adsorption performance of FeMB for RhB. • LED lamps emitting white light were employed as visible light source. • FeMB can be regenerated by visible light photo-Fenton process at circumneutral pH. • FeMB can be reused repeatedly after the heterogeneous photo-Fenton regeneration. - Abstract: Iron modified bentonite (FeMB) was prepared and used as an inexpensive adsorbent to rapidly remove organic pollutant (Rhodamine B, RhB) from aqueous solution. The iron modification significantly improved the adsorption performance of FeMB for RhB and permitted an easy separation of FeMB from the treated effluent. The equilibrium adsorption studies indicated that the dye molecules obeyed Langmuir type of adsorption with the calculated maximum adsorption capacity of 168.13 mg g{sup −1} for FeMB. The heterogeneous photo-Fenton process operated at circumneutral pH in the presence of visible light irradiation was found to be effective for the regeneration of the spent FeMB. Furthermore, the regeneration efficiency of as high as 79% was still achieved after 5 consecutive adsorption-regeneration cycles. Considering that, the visible light photo-Fenton approach could be applied as an excellent alternative for regenerating clay-based adsorbents by avoiding the use of dissolved iron salts.

  19. Iron modified bentonite: Enhanced adsorption performance for organic pollutant and its regeneration by heterogeneous visible light photo-Fenton process at circumneutral pH

    International Nuclear Information System (INIS)

    Gao, Yaowen; Guo, Yongzhao; Zhang, Hui

    2016-01-01

    Highlights: • The iron modification markedly improved the adsorption performance of FeMB for RhB. • LED lamps emitting white light were employed as visible light source. • FeMB can be regenerated by visible light photo-Fenton process at circumneutral pH. • FeMB can be reused repeatedly after the heterogeneous photo-Fenton regeneration. - Abstract: Iron modified bentonite (FeMB) was prepared and used as an inexpensive adsorbent to rapidly remove organic pollutant (Rhodamine B, RhB) from aqueous solution. The iron modification significantly improved the adsorption performance of FeMB for RhB and permitted an easy separation of FeMB from the treated effluent. The equilibrium adsorption studies indicated that the dye molecules obeyed Langmuir type of adsorption with the calculated maximum adsorption capacity of 168.13 mg g"−"1 for FeMB. The heterogeneous photo-Fenton process operated at circumneutral pH in the presence of visible light irradiation was found to be effective for the regeneration of the spent FeMB. Furthermore, the regeneration efficiency of as high as 79% was still achieved after 5 consecutive adsorption-regeneration cycles. Considering that, the visible light photo-Fenton approach could be applied as an excellent alternative for regenerating clay-based adsorbents by avoiding the use of dissolved iron salts.

  20. Photochemical oxidation of short-chain polychlorinated n-alkane mixtures using H2O2/UV and the photo-Fenton reaction

    OpenAIRE

    Ken J. Friesen; Taha M. El-Morsi; Alaa S. Abd-El-Aziz

    2004-01-01

    The photochemical oxidation of a series of short-chain polychlorinated n-alkane (PCA) mixtures was investigated using H2O2/UV and modified photo-Fenton conditions (Fe3+/H2O2/UV) in both Milli-Q and lake water. All PCA mixtures, including chlorinated (Cl5 to Cl8) decanes, undecanes, dodecanes and tridecanes degraded in 0.02 M H2O2/UV at pH 2.8 in pure water, with 80±4% disappearance after 3 h of irradiation using a 300 nm light source. Degradation was somewhat enhanced under similar conditions...

  1. Fenton's syndrome

    International Nuclear Information System (INIS)

    Rimondi, E.; Albasini, V.

    1989-01-01

    The authors report two recent cases of Fenton's syndrome, a very rare carpal fracture-dislocation. After some anatomophysiopathological considerations and a review of the literature, a wider nosographic frame is proposed in which the entity of the dislocation of the head of capitate bone is not essential. According to both the literature and personal findings, the authors remark that this syndrome is always found in the presence of two morphological variants of the distal radioulnar joint. Finally, the authors stress the importance of a corect diagnosis of this lesion to avoid unnecessary attempts of reduction

  2. Degradação de poluentes emergentes por processos Fenton e foto-Fenton

    Directory of Open Access Journals (Sweden)

    Marco A. Benedetti Durigan

    2012-01-01

    Full Text Available A continuous photochemical treatment system was developed for aiming the treatment of aqueous solutions containing relevant micro-pollutants (microcystin-LR, sulfamethoxazole and 17-b estradiol. The continuous photo-Fenton process provided high degradation efficiency. However, contact time between samples and the irradiated region is short relative to total treatment time, indicating that observed changes are predominantly due to the Fenton process. Higher degradation efficiency was observed in systems operated using two treatment cycles, the first involving a batch Fenton process and the second a continuous photo-Fenton treatment.

  3. Ferrous ions reused as catalysts in Fenton-like reactions for remediation of agro-food industrial wastewater.

    Science.gov (United States)

    Leifeld, Vanessa; Dos Santos, Tâmisa Pires Machado; Zelinski, Danielle Wisniewski; Igarashi-Mafra, Luciana

    2018-09-15

    Cassava is the most important tuberous root in tropical and subtropical regions of the world, being the third largest source of carbohydrates. The root processing is related to the production of starch, an important industrial input, which releases a highly toxic liquid wastewater due to its complex composition, which inhibits high performances of conventional effluent treatments. This study aims to evaluate Fenton-like and photo-Fenton-like reactions for treatment of cassava wastewater, reusing ferrous ions from the preliminary coagulation stage. Pre-treated cassava wastewater was submitted to oxidation in three variations of hydrogen peroxide concentrations, with more relevant analytical responses verified in color, turbidity, COD (Chemical Oxygen Demand), and acute toxicity in Artemia salina, besides the action of radicals during Fenton-like reactions. At higher peroxide concentrations, a decrease of 68% in turbidity and 70% in COD on the photo-Fenton-like system was observed, even at slow reaction rates (fastest rate constant k = 2 × 10 -4 min -1 ). Inclusion of UV increases the viability of the Fenton-like reactions by supplementing the reaction medium with hydroxyl radicals, verified by the tert-butanol tests. The oxidation process leads to high EC 50 values in 24 h of incubation in Fenton-like reactions and 48 h in photo-Fenton-like reactions. Final COD and turbidity suggests that the reuse of iron, which remains in the preliminary treatment step shows a great potential as a catalyst for Fenton-like advanced oxidation processes. Tertiary treatment can be less expensive and harmful to the environment, reducing production of residual sludge and metal content in the final effluent, which reduces polluting potential of the effluent regarding solid waste. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Adsorption-regeneration by heterogeneous Fenton process using modified carbon and clay materials for removal of indigo blue.

    Science.gov (United States)

    Almazán-Sánchez, Perla Tatiana; Solache-Ríos, Marcos J; Linares-Hernández, Ivonne; Martínez-Miranda, Verónica

    2016-01-01

    Indigo blue dye is mainly used in dyeing of denim clothes and its presence in water bodies could have adverse effects on the aquatic system; for this reason, the objective of this study was to promote the removal of indigo blue dye from aqueous solutions by iron and copper electrochemically modified clay and activated carbon and the saturated materials were regenerated by a Fenton-like process. Montmorillonite clay was modified at pH 2 and 7; activated carbon at pH 2 and pH of the system. The elemental X-ray dispersive spectroscopy analysis showed that the optimum pH for modification of montmorillonite with iron and copper was 7 and for activated carbon was 2. The dye used in this work was characterized by infrared. Unmodified and modified clay samples showed the highest removal efficiencies of the dye (90-100%) in the pH interval from 2 to 10 whereas the removal efficiencies decrease as pH increases for samples modified at pH 2. Unmodified clay and copper-modified activated carbon at pH 2 were the most efficient activated materials for the removal of the dye. The adsorption kinetics data of all materials were best adjusted to the pseudo-second-order model, indicating a chemisorption mechanism and the adsorption isotherms data showed that the materials have a heterogeneous surface. The iron-modified clay could be regenerated by a photo-Fenton-like process through four adsorption-regeneration cycles, with 90% removal efficiency.

  5. Treatment of combined acid mine drainage (AMD)--flotation circuit effluents from copper mine via Fenton's process.

    Science.gov (United States)

    Mahiroglu, Ayse; Tarlan-Yel, Esra; Sevimli, Mehmet Faik

    2009-07-30

    The treatability of a copper mine wastewater, including heavy metals, AMD, as well as flotation chemicals, with Fenton process was investigated. Fenton process seems advantageous for this treatment, because of Fe(2+) content and low pH of AMD. First, optimum Fe(2+) condition under constant H(2)O(2) was determined, and initial Fe(2+) content of AMD was found sufficient (120 mg/L for removal of chemical oxygen demand (COD) of 6125 mg/L). In the second step, without any additional Fe(2+), optimum H(2)O(2) dosage was determined as 40 mg/L. Fe(2+)/H(2)O(2) molar ratio of 1.8 was enough to achieve the best treatment performance. In all trials, initial pH of AMD was 4.8 and pH adjustment was not performed. Utilization of existing pH and Fe(2+), low H(2)O(2) requirements, and up to 98% treatment performances in COD, turbidity, color, Cu(2+), Zn(2+) made the proposed treatment system promising. Since the reaction occurs stepwise, a two-step kinetic model was applied and calculated theoretical maximum removal rate was consistent to experimental one, which validates the applied model. For the optimum molar ratio (1.8), 140 mL/L sludge of high density (1.094 g/mL), high settling velocity (0.16 cm/s) with low specific resistance (3.15 x 10(8)m/kg) was obtained. High reaction rates and easily dewaterable sludge characteristics also made the proposed method advantageous.

  6. Pretreatment of lignocellulosic biomass using Fenton chemistry

    Science.gov (United States)

    Pretreatment is a necessary step in “biomass to biofuel conversion” due to the recalcitrant nature of lignocellulosic biomass. White-rot fungi utilize peroxidases and hydrogen peroxide (in vivo Fenton chemistry) to degrade lignin. In an attempt to mimic this process, solution phase Fenton chemistry ...

  7. Soil washing in combination with homogeneous Fenton-like oxidation for the removal of 2,4,4'-trichlorodiphenyl from soil contaminated with capacitor oil.

    Science.gov (United States)

    Ma, Xiao-Hong; Zhao, Ling; Lin, Zhi-Rong; Dong, Yuan-Hua

    2016-04-01

    Detoxification by chemical oxidation of polychlorinated biphenyls (PCBs) in contaminated soils is very difficult and inefficient because PCBs typically associate with the solid phase or exist as non-aqueous-phase liquids due to their low solubility and slow desorption rates, and thus, they are difficult to remove from soils by using traditional, water-based elution techniques. Surfactant can enhance washing efficiency of PCBs from contaminated soils. This study used Brij 58, Brij 30, Tween 80, and 2-hydroxypropyl-β-cyclodextrin (HPCD) to solubilize 2,4,4'-trichlorodiphenyl (PCB28) from soil contaminated with capacitor oil into solution. The feasibility of PCB28 oxidation in soil washing wastewater through a Fe(3+)-catalyzed Fenton-like reaction was subsequently examined. Washing with 10 g L(-1) Brij 58 solution showed the highest extraction efficiency (up to 61.5 %) compared with that of the three other surfactants. The total concentration of PCB28 in contaminated soil at 25 °C after 48-h extraction was 286 mg L(-1). In contrast to conditions in which no washing agent was added, addition of the four washing agents decreased the efficiency of PCB28 degradation by the Fenton-like reaction, with the decrease due to addition of 10 g L(-1) Brij 58 solution being the smallest. The optimal concentration of H2O2 for preventing its useless decomposition was found to be 50 mM. The efficiency of PCB28 removal was lower when the initial concentration of PCB28 treated in the Fenton-like reaction was higher. The degradation efficiencies of PCB28 at initial concentrations of 0.1, 10, and 176 mg L(-1) in 10 g L(-1) Brij 58 solution at 25 °C and pH 3.0 and 9 h of reaction using 50 mM H2O2 were 64.1, 42.0, and 34.6 %, respectively. This result indicates that soil washing combined with Fenton-like oxidation may be a practical approach for the remediation of PCB-contaminated soil.

  8. Design of a neutral electro-Fenton system with Fe-Fe2O3/ACF composite cathode for wastewater treatment

    International Nuclear Information System (INIS)

    Li Jinpo; Ai Zhihui; Zhang Lizhi

    2009-01-01

    The narrow pH range limits the wide application of Fenton reaction in the wastewater treatment. It is of great importance to widen working pH range of Fenton reaction from strong acidic condition to neutral, even basic ones. In this study, for the first time nanostructured Fe-Fe 2 O 3 was loaded on active carbon fiber (ACF) as an oxygen diffusion cathode to be used in a heterogeneous electro-Fenton (E-Fenton) oxidation system. This novel Fe-Fe 2 O 3 /ACF composite cathode was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), and element mapping. On the degradation of dye pollutant rhodamine B in water, this heterogeneous E-Fenton system with the Fe-Fe 2 O 3 /ACF cathode showed much higher activity than other E-Fenton systems with commercial zero valent iron powders (Fe 0 ) and ferrous ions (Fe 2+ ) under neutral pH. On the basis of experimental results, we proposed a possible pathway of rhodamine B degradation in this heterogeneous Fe-Fe 2 O 3 /ACF E-Fenton process. This heterogeneous E-Fenton system is very promising to remove organic pollutants in water at neutral pH

  9. Evaluation of three reagent dosing strategies in a photo-Fenton process for the decolorization of azo dye mixtures

    International Nuclear Information System (INIS)

    Prato-Garcia, D.; Buitrón, Germán

    2012-01-01

    Highlights: ► Dosing strategies for a photo-Fenton process were evaluated. ► The dosing strategy had no effect of on the decolorization. ► The type of strategy influenced SUVA index, toxicity reduction and biodegradability. ► A continuous reagents supply was found to be the most adequate strategy. ► Decolorization as well as a less toxic and biodegradable effluent was produced. - Abstract: Three reagent dosing strategies used in the solar photo-assisted decolorization of a mixture of sulfonated dyes consisting of acid blue 113, acid orange 7 and acid red 151 were evaluated. Results demonstrated that the dosing strategy influenced both reagent consumption and the biodegradability and toxicity of the effluent. In one strategy (E 1 ), the Fenton's reactants were dosed in a punctual mode, while in the other two strategies (E 2 an E 3 ), the reactants were dosed continuously. In the E 2 strategy the reactants were dosed by varying the duration of the injection time. In the E 3 strategy, the reactants were dosed during 60 min at a constant rate, but with different concentrations. All cases showed that feeding the reactor between 40% and 60% of the maximal dose was sufficient to decolorize more than 90% of the mixture of azo dyes. The E 1 strategy was less effective for aromatic content reduction. Conversely, the continuous addition of the reagents (E 2 and E 3 strategies) improved the aromatic content removal. E 3 strategy was substantially more appropriate than E 1 strategy due to improved the effluent quality in two key areas: toxicity and biodegradability.

  10. Fenton-like oxidation of 4-chlorophenol using H2O2 in situ generated by Zn-Fe-CNTs composite.

    Science.gov (United States)

    Liu, Yong; Fan, Qing; Liu, Yanlan; Wang, Jianlong

    2018-05-15

    In this paper, a zinc-iron-carbon nanotubes (Zn-Fe-CNTs) composite was prepared, characterized and used to develop a Fenton-like system of Zn-Fe-CNTs/O 2 for the degradation of 4-chlorophenol (4-CP), in which H 2 O 2 was generated in situ from zinc-carbon galvanic cells and oxygen in aqueous solution was activated by iron attached on the surface of CNTs to produce ·OH radicals for the oxidation of 4-CP. The experimental results showed that the particles of Zn and Fe in Zn-Fe-CNTs composite were adhered to the surface of CNTs, which accelerated the electron transfer process. The BET area of Zn-Fe-CNTs composite was 32.9 m 2 /g. The contents of Zn and Fe (% w) in the composite were 44.7% and 4.2%, respectively. The removal efficiency of 4-CP and TOC in Zn-Fe-CNTs/O 2 system was 90.8% and 52.9%, respectively, with the initial pH of 2.0, O 2 flow rate of 800 mL/min, Zn-Fe-CNTs dosage of 1.0 g/L, 4-CP concentration of 50 mg/L and reaction time of 20 min. Based on the analysis of the degradation intermediate products with LC-MS and IC, a possible degradation pathway of 4-CP in Zn-Fe-CNTs/O 2 system was proposed. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Fenton-like chemistry in water: Oxidation catalysis by Fe(III) and H2O2

    NARCIS (Netherlands)

    Ensing, B.; Buda, F.; Baerends, E.J.

    2003-01-01

    The formation of active intermediates from the Fenton-like reagent (a mixture of iron(III) ions and hydrogen peroxide) in aqueous solution has been investigated using static DFT calculations and Car-Parrinello molecular dynamics simulations. We show the spontaneous formation of the iron(III)

  12. Nanocasted synthesis of magnetic mesoporous iron cerium bimetal oxides (MMIC) as an efficient heterogeneous Fenton-like catalyst for oxidation of arsenite

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Zhipan [State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Zhang, Yalei, E-mail: zhangyalei@tongji.edu.cn [State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Dai, Chaomeng [College of Civil Engineering, Tongji University, Shanghai 200092 (China); Sun, Zhen [State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China)

    2015-04-28

    Highlights: • MMIC with large surface area and pore volume was synthesized via the hard template. • MMIC could be easily separated from aqueous solution with an external magnetic field. • MMIC presented excellent catalytic activity for the oxidation of As(III). • As(III) was mainly oxidized by surface-bound ·OH{sub ads} and free ·OH{sub free} radicals. • MMIC played a dual function role for the arsenic removal in aqueous solution. - Abstract: Magnetic mesoporous iron cerium bimetal oxides (MMIC) with large surface area and pore volume was synthesized via the hard template approach. This obtained MMIC was easily separated from aqueous solution with an external magnetic field and was proposed as a heterogeneous Fenton-like catalyst for oxidation of As(III). The MMIC presented excellent catalytic activity for the oxidation of As(III), achieving almost complete oxidation of 1000 ppb As(III) after 60 min and complete removal of arsenic species after 180 min with reaction conditions of 0.4 g/L catalyst, pH of 3.0 and 0.4 mM H{sub 2}O{sub 2}. Kinetics analysis showed that arsenic removal followed the pseudo-first order, and the pseudo-first-order rate constants increased from 0.0014 min{sup −1} to 0.0548 min{sup −1} as the H{sub 2}O{sub 2} concentration increased from 0.04 mM to 0.4 mM. On the basis of the effects of XPS analysis and reactive oxidizing species, As(III) in aqueous solution was mainly oxidized by ·OH radicals, including the surface-bound ·OH{sub ads} generated on the MMIC surface which were involved in ≡Fe{sup 2+} and ≡Ce{sup 3+}, and free ·OH{sub free} generation by soluble iron ions which were released from the MMIC into the bulk solution, and the generated As(V) was finally removed by MMIC through adsorption.

  13. FENTON-DRIVEN REGENERATION OF GRANULAR ACTIVATED CARBON: A TECHNOLOGY OVERVIEW

    Science.gov (United States)

    A Fenton-driven mechanism for regenerating spent granular activated carbon (GAC) involves the combined, synergistic use of two reliable and well established treatment technologies - adsorption onto activated carbon and Fenton oxidation. During carbon adsorption treatment, enviro...

  14. Electrochemical advanced oxidation processes as decentralized water treatment technologies to remediate domestic washing machine effluents.

    Science.gov (United States)

    Dos Santos, Alexsandro Jhones; Costa, Emily Cintia Tossi de Araújo; da Silva, Djalma Ribeiro; Garcia-Segura, Sergi; Martínez-Huitle, Carlos Alberto

    2018-03-01

    Water scarcity is one of the major concerns worldwide. In order to secure this appreciated natural resource, management and development of water treatment technologies are mandatory. One feasible alternative is the consideration of water recycling/reuse at the household scale. Here, the treatment of actual washing machine effluent by electrochemical advanced oxidation processes was considered. Electrochemical oxidation and electro-Fenton technologies can be applied as decentralized small-scale water treatment devices. Therefore, efficient decolorization and total organic abatement have been followed. The results demonstrate the promising performance of solar photoelectro-Fenton process, where complete color and organic removal was attained after 240 min of treatment under optimum conditions by applying a current density of 66.6 mA cm -2 . Thus, electrochemical technologies emerge as promising water-sustainable approaches.

  15. Application of advanced oxidation processes for removing salicylic acid from synthetic wastewaters

    Institute of Scientific and Technical Information of China (English)

    Djalma; Ribeiro; da; Silva; Carlos; A.Martinez-Huítle

    2010-01-01

    In this study,advanced oxidation processes(AOPs) such as anodic oxidation(AO),UV/H_2O_2 and Fenton processes(FP) were investigated for the degradation of salicylic acid(SA) in lab-scale experiments.Boron-doped diamond(BDD) film electrodes using Ta as substrates were employed for AO of SA.In the case of FP and UV/H_2O_2,most favorable experimental conditions were determined for each process and these were used for comparing with AO process.The study showed that the FP was the most effective process under ...

  16. Evaluation of ethyl lactate as solvent in Fenton oxidation for the remediation of total petroleum hydrocarbon (TPH)-contaminated soil.

    Science.gov (United States)

    Jalilian Ahmadkalaei, Seyedeh Pegah; Gan, Suyin; Ng, Hoon Kiat; Abdul Talib, Suhaimi

    2017-07-01

    Due to the health and environmental risks posed by the presence of petroleum-contaminated areas around the world, remediation of petroleum-contaminated soil has drawn much attention from researchers. Combining Fenton reaction with a solvent has been proposed as a novel way to remediate contaminated soils. In this study, a green solvent, ethyl lactate (EL), has been used in conjunction with Fenton's reagents for the remediation of diesel-contaminated soil. The main aim of this research is to determine how the addition of EL affects Fenton reaction for the destruction of total petroleum hydrocarbons (TPHs) within the diesel range. Specifically, the effects of different parameters, including liquid phase volume-to-soil weight (L/S) ratio, hydrogen peroxide (H 2 O 2 ) concentration and EL% on the removal efficiency, have been studied in batch experiments. The results showed that an increase in H 2 O 2 resulted in an increase in removal efficiency of TPH from 68.41% at H 2 O 2  = 0.1 M to 90.21% at H 2 O 2  = 2 M. The lowest L/S, i.e. L/S = 1, had the highest TPH removal efficiency of 85.77%. An increase in EL% up to 10% increased the removal efficiency to 96.74% for TPH, and with further increase in EL%, the removal efficiency of TPH decreased to 89.6%. EL with an optimum value of 10% was found to be best for TPH removal in EL-based Fenton reaction. The power law and pseudo-first order equations fitted well to the experimental kinetic data of Fenton reactions.

  17. Determining the optimal dose of Fenton reagent in a leachate treatment by Fenton-adsorption; Determinacion de la dosis optima de reactivo Fenton en un tratamiento de lixiviados por Fenton-adsorcion

    Energy Technology Data Exchange (ETDEWEB)

    Mendez Novelo, Roger Ivan; Pietrogiovanna Bronca, Jose Alfredo; Santos Ocampo, Beatriz; Sauri Riancho, Maria Rosa; Giacoman Vallejos, German; Castillo Borges, Elba Rene [Universidad Autonoma de Yucatan, Facultad de Ingenieria, Merida, Yucatan (Mexico)]. E-mail: mnovelo@uady.mx

    2010-07-01

    Leachates are formed as a result of the percolation of liquids, through the solid wastes in stabilization process. Their composition is variable and highly toxic; therefore, leachates treatment is a complex task. Due to the high permeability of the soil of the Yucatan Peninsula leachates represent a high risk to health. Fenton type oxidation and adsorption treatment have been tested, and they have showed better results than other types of biological or physicochemical treatment. Fenton process consists in treating the contaminant load with a combination of H{sub 2}O{sub 2} and FeSO{sub 4} under acidic conditions. Experiments were conducted in order to determine if filtration was better than the sedimentation of the sludges. The optimum contact time and the best relations [Fe{sup 2+}]/[H{sub 2}O{sub 2}] and [COD]/[H{sub 2}O{sub 2}] were determined. Subsequently, the oxidized samples were filtered and the adsorption process was tested using two columns in series packed with activated carbon. It was concluded that the sludge generated by the Fenton process was removed more efficiently through filtration than sedimentation. Optimal contact times were 5 min for COD removal, and 1 hour for colour removal; process time was set to one hour in order to protect the activated carbon. The best relations for [Fe{sup 2+}]/[H{sub 2}O{sub 2}] and [COD]/[H{sub 2}O{sub 2}] were 0.6 and 9 respectively. The maximum removal efficiency after the adsorption process was 98.9% for COD and 100% for colour at zero time of the column. A final biodegradability index of 0.24 was reached after the Fenton-adsorption tests. [Spanish] Los lixiviados son el resultado de la percolacion de liquidos a traves de los desechos solidos en proceso de estabilizacion. La complejidad de su tratamiento se debe a que su composicion es altamente toxica y variable. Lo anterior y el suelo altamente permeable de la peninsula de Yucatan, representan un alto peligro a la salud. Se ensayo un tratamiento de oxidacion

  18. Scaled-up electrochemical reactor with a fixed bed three-dimensional cathode for electro-Fenton process: Application to the treatment of bisphenol A

    International Nuclear Information System (INIS)

    Chmayssem, Ayman; Taha, Samir; Hauchard, Didier

    2017-01-01

    In this study, we report on the development of an open undivided electrochemical reactor with a compact fixed bed of glassy carbon pellets as three-dimensional cathode for the application of electro-Fenton process. Bisphenol A (BPA) was chosen as model molecule in order to improve its efficiency to the treatment of persistent pollutants. The study of the BPA removal efficiency in function of the applied current intensity was investigated in order to determine the limiting current of O 2 reduction (optimal conditions of H 2 O 2 production at flow rate of 0.36 m 3 .h −1 ) which was 0.8 A (0.5 A/100 g of glassy carbon pellets). Many parameters have been carried out using this electro-Fenton reactor namely degradation kinetics, influence of anodic reactions on DSA, effect of initial pollutant concentration. In the optimal current condition, the global production rate of H 2 O 2 and ·OH was investigated. The yield of electro-Fenton reaction (conversion of H 2 O 2 to ·OH) was very high (> 90%). The absolute rate of BPA degradation was determined as 4.3 × 10 9 M −1 s −1 . COD, TOC and BOD 5 measurements indicated that only few minutes of treatment by electro-Fenton process were needed to eliminate BPA for dilute solutions (10 and 25 mg.L −1 ). In this case, the biodegradability of the treated solutions occurred rapidly. For higher concentration levels, an efficient removal of BPA appeared for treatment time higher than 1 hour and more than 90 minutes were necessary to obtain the biodegradability of BPA solutions. In optimum conditions, the scale-up of the electrochemical reactor applied to electro-Fenton process was suggested and depended on the concentration level of the pollutant. The operating parameters of the scaled-up reactor might be deduced from the new section of each fixed bed exposed to the flow, from values of liquid flow velocity and from the corresponding limiting current density obtained with the reactor at laboratory scale. The compact fixed bed

  19. Textile wastewater reuse after additional treatment by Fenton's reagent.

    Science.gov (United States)

    Ribeiro, Marília Cleto Meirelles; Starling, Maria Clara V M; Leão, Mônica Maria Diniz; de Amorim, Camila Costa

    2017-03-01

    This study verifies textile wastewater reuse treated by the conventional activated sludge process and subjected to further treatment by advanced oxidation processes. Three alternative processes are discussed: Fenton, photo-Fenton, and UV/H 2 O 2 . Evaluation of treatments effects was based on factorial experiment design in which the response variables were the maximum removal of COD and the minimum concentration of residual H 2 O 2 in treated wastewater. Results indicated Fenton's reagent, COD/[H 2 O 2 ]/[Fe 2+ ] mass ratio of 1:2:2, as the best alternative. The selected technique was applied to real wastewater collected from a conventional treatment plant of a textile mill. The quality of the wastewater before and after the additional treatment was monitored in terms of 16 physicochemical parameters defined as suitable for the characterization of waters subjected to industrial textile use. The degradation of the wastewater was also evaluated by determining the distribution of its molecular weight along with the organic matter fractionation by ultrafiltration, measured in terms of COD. Finally, a sample of the wastewater after additional treatment was tested for reuse at pilot scale in order to evaluate the impact on the quality of dyed fabrics. Results show partial compliance of treated wastewater with the physicochemical quality guidelines for reuse. Removal and conversion of high and medium molecular weight substances into low molecular weight substances was observed, as well as the degradation of most of the organic matter originally present in the wastewater. Reuse tests indicated positive results, confirming the applicability of wastewater reuse after the suggested additional treatment. Graphical abstract Textile wastewater samples after additional treatment by Fenton's reagent, photo-Fenton and H 2 O 2 /UV tested in different conditions.

  20. Oxidation of organic compounds in wastewater from the humid processing of coffee berries; Materiais a base de oxido de ferro para oxidacao de compostos presentes no efluente da despolpa do cafe

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Maraisa; Guerreiro, Mario Cesar; Oliveira, Luiz Carlos Alves; Rocha, Cristian Luciana da [Universidade Federal de Lavras, MG (Brazil). Dept. de Quimica]. E-mail: guerrero@ufla.br

    2008-07-01

    Materials based on pure iron oxide and impregnated with niobia (Nb{sub 2}O{sub 5}) were prepared. Their catalytic activities were tested on the oxidation of compounds present in the wastewater from the processing of coffee berries. Particularly caffeine and catechol were tested. The oxidation reactions were carried out with the following systems: UV/H{sub 2}O{sub 2}; photo-Fenton and heterogeneous Fenton. All materials were characterized with X-ray diffraction, Moessbauer and infrared spectroscopy. Iron was mainly in the forms of goethite and maghemite. The oxidation kinetics were monitored by UV-vis and the oxidation products were monitored by mass spectrometry. The photo-Fenton reaction presented highest oxidation efficiency, removing 98% of all caffeine and catechol contents. (author)

  1. Exquisite Enzyme-Fenton Biomimetic Catalysts for Hydroxyl Radical Production by Mimicking an Enzyme Cascade.

    Science.gov (United States)

    Zhang, Qi; Chen, Shuo; Wang, Hua; Yu, Hongtao

    2018-03-14

    Hydrogen peroxide (H 2 O 2 ) is a key reactant in the Fenton process. As a byproduct of enzymatic reaction, H 2 O 2 can be obtained via catalytical oxidation of glucose using glucose oxidase in the presence of O 2 . Another oxidation product (gluconic acid) can suitably adjust the microenvironmental pH contributing to the Fe 3+ /Fe 2+ cycle in the Fenton reaction. Enzymes are extremely efficient at catalyzing a variety of reactions with high catalytic activity, substrate specificity, and yields in living organisms. Inspired by the multiple functions of natural multienzyme systems, an exquisite nanozyme-modified α-FeOOH/porous carbon (PC) biomimetic catalyst constructed by in situ growth of glucose oxidase-mimicking Au nanoparticles and crystallization of adsorbed ferric ions within carboxyl into hierarchically PC is developed as an efficient enzyme-Fenton catalyst. The products (H 2 O 2 , ∼4.07 mmol·L -1 ) of the first enzymatic reaction are immediately used as substrates for the second Fenton-like reaction to generate the valuable • OH (∼96.84 μmol·L -1 ), thus mimicking an enzyme cascade pathway. α-FeOOH nanocrystals, attached by C-O-Fe bondings, are encapsulated into the mesoporous PC frameworks, facilitating the electron transfer between α-FeOOH and the PC support and greatly suppressing iron leaching. This study paves a new avenue for designing biomimetic enzyme-based Fenton catalysts mimicking a natural system for • OH production.

  2. Investigation of potential genotoxic activity using the SOS Chromotest for real paracetamol wastewater and the wastewater treated by the Fenton process.

    Science.gov (United States)

    Kocak, Emel

    2015-01-01

    The potential genotoxic activity associated with high strength real paracetamol (PCT) wastewater (COD = 40,000 mg/L, TOC = 12,000 mg/L, BOD5 = 19,320 mg/L) from a large-scale drug-producing plant in the Marmara Region, was investigated in pre- and post- treated wastewater by the Fenton process (COD = 2,920 mg/L, TOC = 880 mg/L; BOD5 = 870 mg/L). The SOS Chromotest, which is based on Escherichia coli PQ37 activities, was used for the assessment of genotoxicity. The corrected induction factors (CIF) values used as quantitative measurements of the genotoxic activity were obtained from a total of four different dilutions (100, 50, 6.25, and 0.078 % v/v.) for two samples, in triplicate, to detect potentially genotoxic activities with the SOS Chromotest. The results of the SOS Chromotest demonstrated CIFmax value of 1.24, indicating that the PCT effluent (non-treated) is genotoxic. The results of the SOS Chromotest showed an CIFmax value of 1.72, indicating that the wastewater treated by Fenton process is genotoxic. The findings of this study clearly reveal that the PCT wastewater (non-treated) samples have a potentially hazardous impact on the aquatic environment before treatment, and in the wastewater that was treated by the Fenton process, genotoxicity generally increased.

  3. Simultaneous atrazine degradation and E. coli inactivation by simulated solar photo-Fenton-like process using persulfate.

    Science.gov (United States)

    Garkusheva, Natalya; Matafonova, Galina; Tsenter, Irina; Beck, Sara; Batoev, Valeriy; Linden, Karl

    2017-07-29

    This work evaluated the feasibility of a photo-Fenton-like process using persulfate (PS) and ferrous iron (Fe 2+ ) under simulated solar radiation for degrading the herbicide atrazine (ATZ, 6-Chloro-N-ethyl-N'-isopropyl-1,3,5-triazine-2,4-diamine) and inactivating E. coli. Milli Q water, lake water, and diluted wastewater effluents were spiked both simultaneously and separately with ATZ (4 mg/L) and E. coli (10 5 CFU/mL), and exposed to treatment. A method for determining the average irradiance throughout the water media in the UV(A+B) range of the Xe lamp emission was developed for bench-scale experiments. These values were used to calculate the UV(A+B) fluences and the solar UV(A+B) energy doses per unit of volume (Q UV(A+B) , kJ/L). The obtained kinetic data were presented versus energy dose. Treatment of lake water at near-neutral pH was ineffective via the photo-Fenton-like process, attaining only 20% ATZ removal and 1-log reduction of E. coli. In Milli Q water and wastewater, the complete degradation of ATZ in the absence of bacteria was observed at an average energy dose of 1.5 kJ/L (60 min), while in the presence of cells the degradation efficiency was ∼60%. When ATZ was present, E. coli inactivation was also affected in Milli Q water, with 1.4-log reduction (93%) at a dose of 1.6 kJ/L (60 min), whereas in wastewater complete inactivation was achieved at a lower dose of 1.3 kJ/L (45 min). The energy requirements on a Q UV(A+B) basis for simultaneous 90% ATZ removal and 99.99% E. coli inactivation in Milli Q water and wastewater were shown to be less than 10 kJ/L. This suggests the solar/PS/Fe 2+ system is promising for simultaneous treatment and disinfection of wastewater effluents.

  4. Enhancement the conditioning of waste activated sludge through a sequence of freeze/thaw-electro-Fenton process

    Directory of Open Access Journals (Sweden)

    Shahheidar Narjes

    2018-03-01

    Full Text Available Sludge conditioning is an important stage in sludge management. In the present study, a sequence of freeze/thaw-electro-Fenton process was designed and specific resistance filtration (SRF was monitored during sludge conditioning as an important factor in sludge dewaterability. Furthermore, protein and polysaccharide concentrations were measured during the experiments. Results showed that the lowest SRF value contributed to −10°C in freezing process which showed a reducing trend by decreasing solution pH. In addition, results revealed that solution pH less than 3 caused a significant improvement in sludge dewatering; so the lowest SRF has been registered at pH = 2. By increasing current intensity from 0.5 to 1A, SRF values were reduced and then followed by an enhancement with increasing current intensity to 3.2 A. The lowest SRF value (6.1 × 104 m/kg was obtained at H2O2 = 30 mg/L which was the best conditions for sludge dewatering.

  5. Environmental assessment of different solar driven advanced oxidation processes

    Energy Technology Data Exchange (ETDEWEB)

    Munoz, Ivan; Rieradevall, Joan [Institut de Ciencia i Tecnologia Ambientals (ICTA), Universitat Autonoma de Barcelona, 08193 Bellaterra (Barcelona) (Spain); Torrades, Francesc [Departament d' Enginyeria Quimica, ETSEI de Terrassa, Universitat Politecnica de Catalunya, 08222 Terrassa (Barcelona) (Spain); Peral, Jose; Domenech, Xavier [Departament de Quimica, Universitat Autonoma de Barcelona, 08193 Bellaterra (Barcelona) (Spain)

    2005-10-01

    In this work a comparative environmental assessment of different advanced oxidation processes (AOP's) is performed. Two energy scenarios have been considered according to the energy source used: solar energy and electricity (UVA lamp). A life cycle assessment (LCA) is carried out in order to quantify the environmental impacts of the AOP's. The treatments considered are heterogenous photocatalysis, photo-Fenton reactions, the coupling of heterogeneous photocatalysis and photo-Fenton, and heterogeneous photocatalysis in combination with hydrogen peroxide. These AOP's are applied to the treatment of kraft mill bleaching wastewaters. The system under study includes the production of the catalysts, reagents as well as the production of electricity; eight environmental impact categories are assessed for each AOP: global warming, ozone depletion, aquatic eutrophication, acidification, human toxicity, freshwater aquatic toxicity, photochemical ozone formation, and abiotic resource depletion. the results of the LCA show that the environmental impact of AOP's is caused mainly by the amount of electricity consumed, whereas the impact of producing the reagents and catalysts is comparatively low. For this reason, the solar energy scenario reduces the impact more than 90% for almost all AOP's and impact categories. None of the solar driven AOP's can be identified as the best in all impact categories, but heterogenous photocatalysis and photo-Fenton reactions obtain better results than the remaining treatments, since these treatments do not consume simultaneously both TiO{sub 2} and H{sub 2}O{sub 2}, the chemicals with highest environmental burdens in the system. (author)

  6. Effects of ultrasonic and hydrodynamic cavitation on the treatment of cork wastewater by flocculation and Fenton processes.

    Science.gov (United States)

    Wu, Zhilin; Yuste-Córdoba, Francisco J; Cintas, Pedro; Wu, Zhansheng; Boffa, Luisa; Mantegna, Stefano; Cravotto, Giancarlo

    2018-01-01

    This paper reports that ultrasonic (US) and hydrodynamic cavitation (HC) are efficient strategies for the environmental remediation of cork wastewater (CW). It is necessary to remove toxic, inhibitory or refractory organic matter from CW using physical and chemical techniques (pre-treatment) prior to performing conventional biological treatment. After this biological treatment, it is also critical to further decontaminate (post-treatment) in order to meet the discharge limitation. The pre-treatment of diluted CW using Fenton oxidation (FE) alone led to COD and polyphenol (PP) removal values of 30% and 61%, respectively, while HC and US resulted in 83-90% increases in COD reduction and 26-33% increases in PP reduction. Whereas 55% and 91% COD and PP removal were achieved using flocculation (Floc) alone, COD elimination was increased by a further 7-18% under HC and US. No noticeable improvement in PP elimination was observed. US did not enhance the Floc decontamination of the original concentrated CW, however, considerable quantities of white biofilm were surprisingly generated on the CW surface after the pre-treatment, thus indicating the improvement of biodegradability of the resulting liquid. In fact, the post-treatment stage, using FE alone after having filtered the biofilms, led to reductions of 53% in COD and 90% in PP. The HC and US protocols resulted in 26-34% increases in COD elimination. HC further enhanced PP elimination caused by FE, while US resulted in lower levels of PP elimination. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Comparison of Five Advanced Oxidation Processes for Degradation of Pesticide in Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Augustine Chioma Affam

    2018-01-01

    Full Text Available The study compared the technical efficiency and economic cost of five advanced oxidation processes (Fenton, UV photo-Fenton, solar photo-Fenton, UV/TiO2/H2O2 and FeGAC/H2O2 for degradation of the pesticides chlorpyrifos cypermethrin and chlorothalonil in aqueous solution. The highest degradation in terms of COD and TOC removals and improvement of the biodegradability (BOD5/COD ratio index (BI were observed to be (i Fenton - 69.03% (COD, 55.61% (TOC, and 0.35 (BI; (ii UV photo-Fenton -78.56% (COD, 63.76% (TOC and 0.38 (BI;  (iii solar photo-Fenton - 74.19% (COD, 58.32% (TOC and 0.36 (BI; (iv UV/TiO2/H2O2 - 53.62% (COD, 21.54% (TOC, and 0.26 (BI; and  (v the most technical efficient and cost effective process was FeGAC/H2O2. At an optimum condition (FeGAC 5 g/L, H2O2 100 mg/L, and reaction time of 60 min at pH 3, the COD and TOC removal efficiency were 96.19 and 85.60%, respectively, and the biodegradation index was 0.40. The degradation rate constant and cost were 0.0246 min-1 and $0.74/kg TOC, respectively. The FeGAC/H2O2 process is the most technically efficient and cost effective for pretreatment of the pesticide wastewater before biological treatment. Copyright © 2018 BCREC Group. All rights reserved Received: 26th July 2017; Revised: 26nd September 2017; Accepted: 27th September 2017; Available online: 22nd January 2018; Published regularly: 2nd April 2018 How to Cite: Affam, A.C., Chaudhuri, M., Kutty, S.R.M. (2018. Comparison of Five Advanced Oxidation Processes for Degradation of Pesticide in Aqueous Solution. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (1: 179-186 (doi:10.9767/bcrec.13.1.1394.179-186

  8. Heterogeneous electro-Fenton catalyst for 1-butylpyridinium chloride degradation.

    Science.gov (United States)

    Meijide, Jessica; Pazos, Marta; Sanromán, Maria Ángeles

    2017-10-15

    The application of the electro-Fenton process for organic compound mineralisation has been widely reported over the past years. However, operational problems related to the use of soluble iron salt as a homogeneous catalyst involve the development of novel catalysts that are able to operate in a wide pH range. For this purpose, polyvinyl alcohol-alginate beads, containing goethite as iron, were synthesised and evaluated as heterogeneous electro-Fenton catalyst for 1-butylpyridinium chloride mineralisation. The influence of catalyst dosage and pH solution on ionic liquid degradation was analysed, achieving almost total oxidation after 60 min under optimal conditions (2 g/L catalyst concentration and pH 3). The results showed good catalyst stability and reusability, although its effectiveness decreases slightly after three successive cycles. Furthermore, a plausible mineralisation pathway was proposed based on the oxidation byproducts determined by chromatographic techniques. Finally, the Microtox® test revealed notable detoxification after treatment which demonstrates high catalyst ability for pyridinium-based ionic liquid degradation by the electro-Fenton process.

  9. Partial oxidation process

    International Nuclear Information System (INIS)

    Najjar, M.S.

    1987-01-01

    A process is described for the production of gaseous mixtures comprising H/sub 2/+CO by the partial oxidation of a fuel feedstock comprising a heavy liquid hydrocarbonaceous fuel having a nickel, iron, and vanadium-containing ash or petroleum coke having a nickel, iron, and vanadium-containing ash, or mixtures thereof. The feedstock includes a minimum of 0.5 wt. % of sulfur and the ash includes a minimum of 5.0 wt. % vanadium, a minimum of 0.5 ppm nickel, and a minimum of 0.5 ppm iron. The process comprises: (1) mixing together a copper-containing additive with the fuel feedstock; wherein the weight ratio of copper-containing additive to ash in the fuel feedstock is in the range of about 1.0-10.0, and there is at least 10 parts by weight of copper for each part by weight of vanadium; (2) reacting the mixture from (1) at a temperature in the range of 2200 0 F to 2900 0 F and a pressure in the range of about 5 to 250 atmospheres in a free-flow refactory lined partial oxidation reaction zone with a free-oxygen containing gas in the presence of a temperature moderator and in a reducing atmosphere to produce a hot raw effluent gas stream comprising H/sub 2/+CO and entrained molten slag; and where in the reaction zone and the copper-containing additive combines with at least a portion of the nickel and iron constituents and sulfur found in the feedstock to produce a liquid phase washing agent that collects and transports at least a portion of the vanadium-containing oxide laths and spinels and other ash components and refractory out of the reaction zone; and (3) separating nongaseous materials from the hot raw effluent gas stream

  10. Sequential pretreatment for cell disintegration of municipal sludge in a neutral Bio-electro-Fenton system.

    Science.gov (United States)

    Yu, Qilin; Jin, Xiaochen; Zhang, Yaobin

    2018-05-15

    Sludge cell disruption was generally considered as the rate-limiting step for the anaerobic digestion of waste activated sludge (WAS). Advanced oxidation processes and bio-electro-chemical systems were recently reported to enhance the hydrolysis of WAS and sludge cell disruption, while the cell-breaking processes of these systems remain unclear yet. In this study, an innovative Bio-electro-Fenton system was developed to pretreat the WAS sequentially with cathode Fenton process and anode anaerobic digestion. Significant cell disruption and dissolution intracellular organics were founded after the treatment. X-ray photoelectron spectroscopy (XPS) analysis and fourier transform infrared spectroscopy (FT-IR) spectra indicated that Gram-negative bacteria were more sensitive to free radicals yielded in cathode to induce a chain reaction that destroyed the lipid-contained outer membrane, while Gram-positive bacteria with thick peptidoglycan layer were liable to be biologically decomposed in the anode. Compared with the oxidation of organic matters in the cathode Fenton, the secretion of enzyme increased in the anode which was beneficial to break down the complex matters (peptidoglycans) into simples that were available for anode oxidation by exoelectrogens. The results also showed a possible prospect for the application of this sequential pretreatment in bio-electro-Fenton systems to disrupt sludge cells and enhance the anaerobic digestion. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Photo-Fenton degradation of the insecticide esfenvalerate in aqueous medium using a recirculation flow-through UV photoreactor

    International Nuclear Information System (INIS)

    Colombo, Renata; Ferreira, Tanare C.R.; Alves, Suellen A.; Lanza, Marcos R.V.

    2011-01-01

    Highlights: ► The photo-Fenton reaction provides an efficient process by which to degrade esfenvalerate in aqueous suspensions. ► Photo-Fenton oxidation with Fe 3+ is more efficient in degrading esfenvalerate than the Fe 2+ -based reaction. ► Esfenvalerate was degraded most efficiently by photo-Fenton reaction in the presence of 5 mM Fe 3+ complex and 25 mM hydrogen peroxide at pH 2.5. ► The degradation of esfenvalerate by photo-Fenton (Fe 3+ ) generates organic by-products. ► Organic compounds present in commercial esfenvalerate-based insecticides affect the degradation process. - Abstract: The aim of the study was to evaluate the efficiencies of photo-Fenton (Fe 2+ ) and (Fe 3+ ) processes in the degradation of high-concentrations of esfenvalerate (in the form of aqueous emulsion of a commercial formulation) using a recirculation flow-through photoreactor irradiated with UV light from a 15 W lamp (254 nm emission peak). The results obtained using a basic photo-Fenton (Fe 2+ ) reaction (esfenvalerate 17 mg L −1 ; ferrous sulphate 1 mM; hydrogen peroxide 25 mM; pH 2.5) were compared with those acquired when ferrioxalate (1, 3 or 5 mM) served as the iron source. Degradation of the active component of the commercial formulation was significantly greater, and the rate of oxidation more rapid, using a photo-Fenton (Fe 3+ ) process compared with its Fe 2+ counterpart. The most efficient degradation of the insecticide (75% in 180 min) was achieved with a reaction mixture containing 5 mM ferrioxalate. However, under the same experimental conditions, degradation of pure esfenvalerate preceded much faster (99% in 60 min) and was 100% complete within 180 min reaction time.

  12. Fenton's reagent as a remediation process in water treatment: application to the degradation of polycyclic aromatic hydrocarbons in waters and sewage sludges; La reaction de fenton comme procede de rehabilitation dans le traitement des eaux: application a la degradation des hydrocarbures aromatiques polycycliques dans les eaux et les boues residuaires

    Energy Technology Data Exchange (ETDEWEB)

    Flotron, V

    2004-05-15

    This study is related to the application of Fenton's reagent to remedy matrices contaminated by polycyclic aromatic hydrocarbons (PAHs). In aqueous solution, the choice of the reagent implementation is important, in order to generate enough radicals to oxidize pollutants. Degradation of the organic compounds is possible, but a large difference in reactivity is observed between 'alternant' and 'non-alternant' PAHs (with a five carbon atoms cycle). Besides, if a few specific precautions are omitted, the PAHs can sorb onto the flask inside surface, and therefore not undergo oxidation. The results on sewage sludges show that under certain conditions (high reagent concentrations), the pollutants can be oxidised although they are adsorbed. Moreover, it appears that the matrix itself plays an important role, as the iron oxides seem to be able to decompose hydrogen peroxide, and thus initiate Fenton reaction. Its application to contaminated soils and sediments is also possible. (author)

  13. Fenton's reagent as a remediation process in water treatment: application to the degradation of polycyclic aromatic hydrocarbons in waters and sewage sludges; La reaction de fenton comme procede de rehabilitation dans le traitement des eaux: application a la degradation des hydrocarbures aromatiques polycycliques dans les eaux et les boues residuaires

    Energy Technology Data Exchange (ETDEWEB)

    Flotron, V.

    2004-05-15

    This study is related to the application of Fenton's reagent to remedy matrices contaminated by polycyclic aromatic hydrocarbons (PAHs). In aqueous solution, the choice of the reagent implementation is important, in order to generate enough radicals to oxidize pollutants. Degradation of the organic compounds is possible, but a large difference in reactivity is observed between 'alternant' and 'non-alternant' PAHs (with a five carbon atoms cycle). Besides, if a few specific precautions are omitted, the PAHs can sorb onto the flask inside surface, and therefore not undergo oxidation. The results on sewage sludges show that under certain conditions (high reagent concentrations), the pollutants can be oxidised although they are adsorbed. Moreover, it appears that the matrix itself plays an important role, as the iron oxides seem to be able to decompose hydrogen peroxide, and thus initiate Fenton reaction. Its application to contaminated soils and sediments is also possible. (author)

  14. Advanced oxidation process-biological system for wastewater containing a recalcitrant pollutant.

    Science.gov (United States)

    Oller, I; Malato, S; Sánchez-Pérez, J A; Maldonado, M I; Gernjak, W; Pérez-Estrada, L A

    2007-01-01

    Two advanced oxidation processes (AOPs), ozonation and photo-Fenton, combined with a pilot aerobic biological reactor at field scale were employed for the treatment of industrial non-biodegradable saline wastewater (TOC around 200 mgL(-1)) containing a biorecalcitrant compound, alpha-methylphenylglycine (MPG), at a concentration of 500 mgL(-1). Ozonation experiments were performed in a 50-L reactor with constant inlet ozone of 21.9 g m(-3). Solar photo-Fenton tests were carried out in a 75-L pilot plant made up of four compound parabolic collector (CPC) units. The catalyst concentration employed in this system was 20 mgL(-1) of Fe2+ and the H2O2 concentration was kept in the range of 200-500mgL(-1). Complete degradation of MPG was attained after 1,020 min of ozone treatment, while only 195 min were required for photo-Fenton. Samples from different stages of both AOPs were taken for Zahn-Wellens biocompatibility tests. Biodegradability enhancement of the industrial saline wastewater was confirmed (>70% biodegradability). Biodegradable compounds generated during the preliminary oxidative processes were biologically mineralised in a 170-L aerobic immobilised biomass reactor (IBR). The global efficiency of both AOP/biological combined systems was 90% removal of an initial TOC of over 500 mgL(-1).

  15. Sulfamethoxazole abatement by photo-Fenton

    International Nuclear Information System (INIS)

    Gonzalez, Oscar; Sans, Carme; Esplugas, Santiago

    2007-01-01

    The objective of this work was to study the abatement of 200 mg L -1 sulfamethoxazole (SMX) solution by means of photo-Fenton process. Biodegradability of the treated solutions was followed by the ratio biochemical oxygen demand at five days/chemical oxygen demand (BOD 5 /COD) and toxicity by Microtox[reg] and inhibition tests. Experiments with different initial concentration of H 2 O 2 were carried out. The initial amount of Fe 2+ and pH of the solution were set at 10 mg L -1 and 2.8 respectively. The temperature of the reactor was kept constant in all the experiments (25 ± 0.8 deg. C). Photo-Fenton process is thought to be a successful treatment step to improve the biodegradability of wastewater containing SMX. The complete antibiotic removal was achieved for a H 2 O 2 dose over 300 mg L -1 . Biodegradability (BOD 5 /COD) rose from zero (SMX solution) to values higher than 0.3 (treated solutions). Toxicity and inhibition tests pointed out in the same direction: oxidized intermediates for initial H 2 O 2 dose over 300 mg L -1 showed no toxicity effects on pure bacteria and no inhibition on activated sludge activity

  16. Involvement of Fenton chemistry in rice straw degradation by the lignocellulolytic bacterium Pantoea ananatis Sd-1.

    Science.gov (United States)

    Ma, Jiangshan; Zhang, Keke; Huang, Mei; Hector, Stanton B; Liu, Bin; Tong, Chunyi; Liu, Qian; Zeng, Jiarui; Gao, Yan; Xu, Ting; Liu, Ying; Liu, Xuanming; Zhu, Yonghua

    2016-01-01

    Lignocellulolytic bacteria have revealed to be a promising source for biofuel production, yet the underlying mechanisms are still worth exploring. Our previous study inferred that the highly efficient lignocellulose degradation by bacterium Pantoea ananatis Sd-1 might involve Fenton chemistry (Fe 2+  + H 2 O 2  + H +  → Fe 3+  + OH· + H 2 O), similar to that of white-rot and brown-rot fungi. The aim of this work is to investigate the existence of this Fenton-based oxidation mechanism in the rice straw degradation process of P. ananatis Sd-1. After 3 days incubation of unpretreated rice straw with P. ananatis Sd-1, the percentage in weight reduction of rice straw as well as its cellulose, hemicellulose, and lignin components reached 46.7, 43.1, 42.9, and 37.9 %, respectively. The addition of different hydroxyl radical scavengers resulted in a significant decline ( P  Fenton reagent treatment. In addition to the increased total iron ion concentration throughout the rice straw decomposition process, the Fe 3+ -reducing capacity of P. ananatis Sd-1 was induced by rice straw and predominantly contributed by aromatic compounds metabolites. The transcript levels of the glucose-methanol-choline oxidoreductase gene related to hydrogen peroxide production were significantly up-regulated (at least P  Fenton-like reactions. Our results confirmed the Fenton chemistry-assisted degradation model in P. ananatis Sd-1. We are among the first to show that a Fenton-based oxidation mechanism exists in a bacteria degradation system, which provides a new perspective for how natural plant biomass is decomposed by bacteria. This degradative system may offer an alternative approach to the fungi system for lignocellulosic biofuels production.

  17. Preparative treatment with NaOH to selectively concentrate iron oxides of a Chilean volcanic soil material to produce effective heterogeneous Fenton catalyst

    International Nuclear Information System (INIS)

    Manzo, Valentina; Pizarro, Carmen; Rubio, María Angélica; Cavalcante, Luis Carlos Duarte; Garg, Vijayendra Kumar; Fabris, José Domingos

    2011-01-01

    A Chilean volcanic Ultisol material was first size-fractionated so as to obtain the fraction with mean particle sizes φ   − 1 NaOH, in an attempt to evaluate the effectiveness of the selective chemical dissolution to concentrate iron oxides, as a preparation procedure before using the materials as heterogeneous Fenton catalysts. The effects of those treatments on the iron oxides mineralogy were monitored with Mössbauer spectroscopy. The NaOH-treated samples were tested as catalysts towards the H 2 O 2 decomposition. Three or five sequential NaOH treatments were found to be comparably effective, by concentrating nearly the same proportion of iron oxides in the remaining solid phase (25.1 ± 0.4 and 23.3 ± 0.2 mass%, respectively). 298 K-Mössbauer patterns were similar for both samples, with a central (super)paramagnetic Fe 3 +  doublet and a broad sextet, assignable to several closely coexisting magnetically ordered forms of iron oxides. Despite of this nearly similar effect of the two treatments, the Ultisol material treated three times with NaOH presents higher heterogeneous catalytic efficiency and is more suitable to decompose H 2 O 2 than that with five treatments.

  18. Sulfate radicals induced from peroxymonosulfate by cobalt manganese oxides (Co{sub x}Mn{sub 3−x}O{sub 4}) for Fenton-Like reaction in water

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Yunjin, E-mail: yaoyunjin@gmail.com [Anhui Key Lab of Controllable Chemical Reaction & Material Chemical Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Tunxi Road 193, Hefei 230009 (China); State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China); School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui 230026 (China); Cai, Yunmu; Wu, Guodong; Wei, Fengyu [Anhui Key Lab of Controllable Chemical Reaction & Material Chemical Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Tunxi Road 193, Hefei 230009 (China); Li, Xingya [School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui 230026 (China); Chen, Hao [Anhui Key Lab of Controllable Chemical Reaction & Material Chemical Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Tunxi Road 193, Hefei 230009 (China); Wang, Shaobin, E-mail: shaobin.wang@curtin.edu.au [Department of Chemical Engineering, Curtin University, G.P.O. Box U1987, Perth, Western Australia 6845 (Australia)

    2015-10-15

    Highlights: • A series of Co{sub x}Mn{sub 3−x}O{sub 4} particles as Fenton-like solid catalysts were synthesized. • CoMn{sub 2}O{sub 4}/PMS exhibits high activity due to synergistic effects of Co and Mn species. • Reaction conditions and degradation mechanism have been analyzed. • Contributions from SO{sub 4}·{sup −} and HO· radicals to the reaction were measured using scavengers. • The catalyst had good stability and reusability during the five successive runs. - Abstract: A series of Co{sub x}Mn{sub 3−x}O{sub 4} particles as Fenton-like solid catalysts were synthesized, and their catalytic performance in oxidative degradation of organic dye compounds in water was investigated. The surface morphology and structure of the Co{sub x}Mn{sub 3−x}O{sub 4} catalysts were characterized by field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results showed that, as an oxide composite of Co and Mn elements, CoMn{sub 2}O{sub 4} showed much stronger catalytic activity in peroxymonosulfate (PMS) oxidation than Co{sub 3}O{sub 4}, Mn{sub 2}O{sub 3,} and their physical mixture. Typically, the uses of 0.02 g/dm{sup 3} CoMn{sub 2}O{sub 4} and 0.2 g/dm{sup 3} PMS yielded a nearly complete removal of Rhodamine B (0.03 g/dm{sup 3}) in 80 min at 25 °C. The efficiency of Rhodamine B decomposition increased with increasing temperature (15–55 °C), but decreased with the increase of fulvic acid concentration (0–0.08 g/dm{sup 3}). Furthermore, CoMn{sub 2}O{sub 4} could maintain its catalytic activity in the repeated batch experiments. Moreover, HO· and SO{sub 4}·{sup −} radicals participating in the process were evidenced using quenching experiments, and a rational mechanism was proposed. PMS oxidation with CoMn{sub 2}O{sub 4} is an efficient technique for remediation of organic contaminants in

  19. Degradation of the fluoroquinolone enrofloxacin by electrochemical advanced oxidation processes based on hydrogen peroxide electrogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Guinea, Elena; Garrido, Jose Antonio; Rodriguez, Rosa Maria; Cabot, Pere-Lluis; Arias, Conchita; Centellas, Francesc [Laboratori d' Electroquimica dels Materials i del Medi Ambient, Departament de Quimica Fisica, Facultat de Quimica, Universitat de Barcelona, Marti i Franques 1-11, 08028 Barcelona (Spain); Brillas, Enric, E-mail: brillas@ub.ed [Laboratori d' Electroquimica dels Materials i del Medi Ambient, Departament de Quimica Fisica, Facultat de Quimica, Universitat de Barcelona, Marti i Franques 1-11, 08028 Barcelona (Spain)

    2010-02-15

    Solutions of the veterinary fluoroquinolone antibiotic enrofloxacin in 0.05 M Na{sub 2}SO{sub 4} of pH 3.0 have been comparatively degraded by electrochemical advanced oxidation processes such as anodic oxidation with electrogenerated H{sub 2}O{sub 2} (AO-H{sub 2}O{sub 2}), electro-Fenton (EF), photoelectro-Fenton (PEF) and solar photoelectro-Fenton (SPEF) at constant current density. The study has been performed using an undivided stirred tank reactor of 100 ml and a batch recirculation flow plant of 2.5 l with an undivided filter-press cell coupled to a solar photoreactor, both equipped with a Pt or boron-doped diamond (BDD) anode and a carbon-polytetrafluoroethylene gas diffusion cathode to generate H{sub 2}O{sub 2} from O{sub 2} reduction. In EF, PEF and SPEF, hydroxyl radical (centre dotOH) is formed from Fenton's reaction between added catalytic Fe{sup 2+} and generated H{sub 2}O{sub 2}. Almost total decontamination of enrofloxacin solutions is achieved in the stirred tank reactor by SPEF with BDD. The use of the batch recirculation flow plant showed that this process is the most efficient and can be viable for industrial application, becoming more economic and yielding higher mineralization degree with raising antibiotic content. This is feasible because organics are quickly oxidized with centre dotOH formed from Fenton's reaction and at BDD from water oxidation, combined with the fast photolysis of complexes of Fe(III) with generated carboxylic acids under solar irradiation. The lower intensity of UVA irradiation used in PEF with BDD causes a slower degradation. EF with BDD is less efficient since centre dotOH cannot destroy the most persistent Fe(III)-oxalate and Fe(III)-oxamate complexes. AO-H{sub 2}O{sub 2} with BDD yields the poorest mineralization because pollutants are only removed with centre dotOH generated at BDD. All procedures are less potent using Pt as anode due to the lower production of centre dotOH at its surface. Enrofloxacin

  20. Degradation of the fluoroquinolone enrofloxacin by electrochemical advanced oxidation processes based on hydrogen peroxide electrogeneration

    International Nuclear Information System (INIS)

    Guinea, Elena; Garrido, Jose Antonio; Rodriguez, Rosa Maria; Cabot, Pere-Lluis; Arias, Conchita; Centellas, Francesc; Brillas, Enric

    2010-01-01

    Solutions of the veterinary fluoroquinolone antibiotic enrofloxacin in 0.05 M Na 2 SO 4 of pH 3.0 have been comparatively degraded by electrochemical advanced oxidation processes such as anodic oxidation with electrogenerated H 2 O 2 (AO-H 2 O 2 ), electro-Fenton (EF), photoelectro-Fenton (PEF) and solar photoelectro-Fenton (SPEF) at constant current density. The study has been performed using an undivided stirred tank reactor of 100 ml and a batch recirculation flow plant of 2.5 l with an undivided filter-press cell coupled to a solar photoreactor, both equipped with a Pt or boron-doped diamond (BDD) anode and a carbon-polytetrafluoroethylene gas diffusion cathode to generate H 2 O 2 from O 2 reduction. In EF, PEF and SPEF, hydroxyl radical (·OH) is formed from Fenton's reaction between added catalytic Fe 2+ and generated H 2 O 2 . Almost total decontamination of enrofloxacin solutions is achieved in the stirred tank reactor by SPEF with BDD. The use of the batch recirculation flow plant showed that this process is the most efficient and can be viable for industrial application, becoming more economic and yielding higher mineralization degree with raising antibiotic content. This is feasible because organics are quickly oxidized with ·OH formed from Fenton's reaction and at BDD from water oxidation, combined with the fast photolysis of complexes of Fe(III) with generated carboxylic acids under solar irradiation. The lower intensity of UVA irradiation used in PEF with BDD causes a slower degradation. EF with BDD is less efficient since ·OH cannot destroy the most persistent Fe(III)-oxalate and Fe(III)-oxamate complexes. AO-H 2 O 2 with BDD yields the poorest mineralization because pollutants are only removed with ·OH generated at BDD. All procedures are less potent using Pt as anode due to the lower production of ·OH at its surface. Enrofloxacin decay always follows a pseudo first-order reaction. Its primary aromatic by-products and short intermediates

  1. Vanillic and syringic acids from biomass burning: Behaviour during Fenton-like oxidation in atmospheric aqueous phase and in the absence of light

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Gabriela T.A.D.; Santos, Patrícia S.M., E-mail: patricia.santos@ua.pt; Duarte, Armando C.

    2016-08-05

    Highlights: • The rate of oxidation of small aromatic acids increase with the pH decrease. • With the oxidation of aromatic acids are formed new small aromatic compounds. • The initial and formed compounds are not totally degraded during the night period. • The substituents and their positions in ring affect the oxidation of aromatic acids. • The OH radical attack to vanillic and syringic acids is different in atmospheric waters. - Abstract: Biomass combustion is a threat to the environment since it emits to the atmosphere organic compounds, which may react and originate others more aggressive. This work studied the behaviours of vanillic and syringic acids, small aromatic tracers of biomass burning, during Fenton-like oxidation in aqueous phase and absence of light. For both compounds, the extent of oxidation increased with pH decrease from neutral to acid in atmospheric waters, but for vanillic acid the neutral pH was not able of promoting the oxidation. With the oxidation of both acids were formed chromophoric compounds, and the formation rate increased with the degree of electron-donator substituents in benzene ring. The initial and produced compounds were not totally degraded up to 24 h of reaction at pH 4.5, suggesting that the night period may be not sufficient for their full degradation in atmospheric waters. The major compounds formed were the 3,4-dihydroxybenzoic acid for vanillic acid, and the 1,4-dihydroxy-2,6-dimethoxybenzene for syringic acid. These findings suggest the occurrence of an ipso attack by the hydroxyl radical preferential to the methoxy and carboxyl groups of vanillic and syringic acids, respectively. It is important to highlight that for both aromatic acids the main compounds produced are also small aromatic compounds.

  2. Hydrometallurgical recovery of heavy metals from low grade automobile shredder residue (ASR): An application of advanced Fenton process (AFP).

    Science.gov (United States)

    Singh, Jiwan; Lee, Byeong-Kyu

    2015-09-15

    To investigate the leaching and recovery of heavy metals from low-grade automobile shredder residue (ASR), the effects of nitric acid (HNO3) and hydrogen peroxide (H2O2) concentrations, liquid/solid (L/S) ratio, leaching temperature and ASR particle size fractions on the heavy metal leaching rate were determined. The heavy metals were recovered by fractional precipitation and advanced Fenton process (AFP) at different pHs. The toxicity characteristic leaching procedure (TCLP) test was also performed in the residue remaining after heavy metal leaching to evaluate the potential toxicity of ASR. The heavy metal leaching efficiency was increased with increasing HNO3 and H2O2 concentrations, L/S ratio and temperature. The heavy metal leaching efficiencies were maximized in the lowest ASR size fraction at 303 K and L/S ratio of 100 mL/g. The kinetic study showed that the metal leaching was best represented by a second-order reaction model, with a value of R(2) > 0.99 for all selected heavy metals. The determined activation energy (kJ/mol) was 21.61, 17.10, 12.15, 34.50, 13.07 and 11.45 for Zn, Fe, Ni, Pb, Cd and Cr, respectively. In the final residue, the concentrations of Cd, Cr and Pb were under their threshold limits in all ASR size fractions. Hydrometallurgical metal recovery was greatly increased by AFP up to 99.96% for Zn, 99.97% for Fe, 95.62% for Ni, 99.62% for Pb, 94.11% for Cd and 96.79% for Cr. AFP is highly recommended for the recovery of leached metals from solution even at low concentrations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Thimerosal-Derived Ethylmercury Is a Mitochondrial Toxin in Human Astrocytes: Possible Role of Fenton Chemistry in the Oxidation and Breakage of mtDNA

    Directory of Open Access Journals (Sweden)

    Martyn A. Sharpe

    2012-01-01

    Full Text Available Thimerosal generates ethylmercury in aqueous solution and is widely used as preservative. We have investigated the toxicology of Thimerosal in normal human astrocytes, paying particular attention to mitochondrial function and the generation of specific oxidants. We find that ethylmercury not only inhibits mitochondrial respiration leading to a drop in the steady state membrane potential, but also concurrent with these phenomena increases the formation of superoxide, hydrogen peroxide, and Fenton/Haber-Weiss generated hydroxyl radical. These oxidants increase the levels of cellular aldehyde/ketones. Additionally, we find a five-fold increase in the levels of oxidant damaged mitochondrial DNA bases and increases in the levels of mtDNA nicks and blunt-ended breaks. Highly damaged mitochondria are characterized by having very low membrane potentials, increased superoxide/hydrogen peroxide production, and extensively damaged mtDNA and proteins. These mitochondria appear to have undergone a permeability transition, an observation supported by the five-fold increase in Caspase-3 activity observed after Thimerosal treatment.

  4. Comparison of three combined sequencing batch reactor followed by enhanced Fenton process for an azo dye degradation: Bio-decolorization kinetics study

    Energy Technology Data Exchange (ETDEWEB)

    Azizi, A., E-mail: armina_84@yahoo.com [Civil and Environmental Engineering Department, Amirkabir University of Technology, Hafez Ave., Tehran15875-4413 (Iran, Islamic Republic of); Alavi Moghaddam, M.R., E-mail: alavim@yahoo.com [Civil and Environmental Engineering Department, Amirkabir University of Technology, Hafez Ave., Tehran15875-4413 (Iran, Islamic Republic of); Maknoon, R., E-mail: rmaknoon@yahoo.com [Civil and Environmental Engineering Department, Amirkabir University of Technology, Hafez Ave., Tehran15875-4413 (Iran, Islamic Republic of); Kowsari, E., E-mail: kowsarie@aut.ac.ir [Department of Chemistry, Amirkabir University of Technology, Hafez Ave., Tehran 15875-4413 (Iran, Islamic Republic of)

    2015-12-15

    Highlights: • Three combined advanced SBR and enhanced Fenton process as post treatment was compared. • Higher biomass concentration, dye, COD and metabolites removal was presented together. • Pseudo zero and pseudo first-order bio-decolorization kinetics were observed in all SBRs. • High reduction of AR18 to intermediate metabolites was monitored by HPLC. - Abstract: The purpose of this research was to compare three combined sequencing batch reactor (SBR) – Fenton processes as post-treatment for the treatment of azo dye Acid Red 18 (AR18). Three combined treatment systems (CTS1, CTS2 and CTS3) were operated to investigate the biomass concentration, COD removal, AR18 dye decolorization and kinetics study. The MLSS concentration of CTS2 reached 7200 mg/L due to the use of external feeding in the SBR reactor of CTS2. The COD concentration remained 273 mg/L and 95 mg/L (initial COD = 3270 mg/L) at the end of alternating anaerobic–aerobic SBR with external feeding (An-A MSBR) and CTS2, respectively, resulting in almost 65% of Fenton process efficiency. The dye concentration of 500 mg/L was finally reduced to less than 10 mg/L in all systems indicating almost complete AR18 decolorization, which was also confirmed by UV–vis analysis. The dye was removed following two successive parts as parts 1 and 2 with pseudo zero-order and pseudo first-order kinetics, respectively, in all CTSs. Higher intermediate metabolites degradation was obtained using HPLC analysis in CTS2. Accordingly, a combined treatment system can be proposed as an appropriate and environmentally-friendly system for the treatment of the azo dye AR18 in wastewater.

  5. Coupling of acrylic dyeing wastewater treatment by heterogeneous Fenton oxidation in a continuous stirred tank reactor with biological degradation in a sequential batch reactor.

    Science.gov (United States)

    Esteves, Bruno M; Rodrigues, Carmen S D; Boaventura, Rui A R; Maldonado-Hódar, F J; Madeira, Luís M

    2016-01-15

    This work deals with the treatment of a recalcitrant effluent, from the dyeing stage of acrylic fibres, by combination of the heterogeneous Fenton's process in a continuous stirred tank reactor (CSTR) with biological degradation in a sequential batch reactor (SBR). Three different catalysts (a commercial Fe/ZSM-5 zeolite and two distinct Fe-containing activated carbons - ACs - prepared by wet impregnation of iron acetate and iron nitrate) were employed on the Fenton's process, and afterwards a parametric study was carried out to determine the effect of the main operating conditions, namely the hydrogen peroxide feed concentration, temperature and contact time. Under the best operating conditions found, using the activated carbon impregnated with iron nitrate, 62.7% of discolouration and 39.9% of total organic carbon (TOC) reduction were achieved, at steady-state. Furthermore, a considerable increase in the effluent's biodegradability was attained (BOD5:COD ratio increased from <0.001 to 0.27 and SOUR - specific oxygen uptake rate - from <0.2 to 11.1 mg O2/(gVSS·h)), alongside a major decrease in its toxicity (from 92.1 to 94.0% of Vibrio fischeri inhibition down to 6.9-9.9%). This allowed the application of the subsequent biological degradation stage. The combination of the two processes provided a treated effluent that clearly complies with the legislated discharge limits. It was also found that the iron leaching from the three catalysts tested was very small in all runs, a crucial factor for the stability and long-term use of such materials. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Remediação de solos contaminados por processos fenton: uma revisão crítica

    Directory of Open Access Journals (Sweden)

    Alecsandra dos Santos

    Full Text Available The remediation of contaminated soils is probably one of the biggest environmental challenges, mainly due to the complex dynamics of the pollutants in this medium. Among a variety of treatment alternatives proposed for the in-situ remediation of contaminated soils, Fenton processes appear as the most cost-effective, particularly when catalyzed by native iron oxides. However, both the efficiency of the Fenton process and its effect on the treated soil, are largely dependent of the treatment conditions and the main characteristics of the soil, which implies the nonexistence of universal procedures. In this work, the use of Fenton processes in soil remediation routines is critically evaluated, emphasizing aspects related to the degradation efficiency, the influence of the soil properties, the degradation mechanisms and the impacts on the treated soil.

  7. Combined treatment technology based on synergism between hydrodynamic cavitation and advanced oxidation processes.

    Science.gov (United States)

    Gogate, Parag R; Patil, Pankaj N

    2015-07-01

    The present work highlights the novel approach of combination of hydrodynamic cavitation and advanced oxidation processes for wastewater treatment. The initial part of the work concentrates on the critical analysis of the literature related to the combined approaches based on hydrodynamic cavitation followed by a case study of triazophos degradation using different approaches. The analysis of different combinations based on hydrodynamic cavitation with the Fenton chemistry, advanced Fenton chemistry, ozonation, photocatalytic oxidation, and use of hydrogen peroxide has been highlighted with recommendations for important design parameters. Subsequently degradation of triazophos pesticide in aqueous solution (20 ppm solution of commercially available triazophos pesticide) has been investigated using hydrodynamic cavitation and ozonation operated individually and in combination for the first time. Effect of different operating parameters like inlet pressure (1-8 bar) and initial pH (2.5-8) have been investigated initially. The effect of addition of Fenton's reagent at different loadings on the extent of degradation has also been investigated. The combined method of hydrodynamic cavitation and ozone has been studied using two approaches of injecting ozone in the solution tank and at the orifice (at the flow rate of 0.576 g/h and 1.95 g/h). About 50% degradation of triazophos was achieved by hydrodynamic cavitation alone under optimized operating parameters. About 80% degradation of triazophos was achieved by combination of hydrodynamic cavitation and Fenton's reagent whereas complete degradation was achieved using combination of hydrodynamic cavitation and ozonation. TOC removal of 96% was also obtained for the combination of ozone and hydrodynamic cavitation making it the best treatment strategy for removal of triazophos. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. A bionic system with Fenton reaction and bacteria as a model for bioprocessing lignocellulosic biomass.

    Science.gov (United States)

    Zhang, Kejing; Si, Mengying; Liu, Dan; Zhuo, Shengnan; Liu, Mingren; Liu, Hui; Yan, Xu; Shi, Yan

    2018-01-01

    The recalcitrance of lignocellulosic biomass offers a series of challenges for biochemical processing into biofuels and bio-products. For the first time, we address these challenges with a biomimetic system via a mild yet rapid Fenton reaction and lignocellulose-degrading bacterial strain Cupriavidus basilensis B-8 (here after B-8) to pretreat the rice straw (RS) by mimicking the natural fungal invasion process. Here, we also elaborated the mechanism through conducting a systematic study of physicochemical changes before and after pretreatment. After synergistic Fenton and B-8 pretreatment, the reducing sugar yield was increased by 15.6-56.6% over Fenton pretreatment alone and 2.7-5.2 times over untreated RS (98 mg g -1 ). Morphological analysis revealed that pretreatment changed the surface morphology of the RS, and the increase in roughness and hydrophilic sites enhanced lignocellulose bioavailability. Chemical components analyses showed that B-8 removed part of the lignin and hemicellulose which caused the cellulose content to increase. In addition, the important chemical modifications also occurred in lignin, 2D NMR analysis of the lignin in residues indicated that the Fenton pretreatment caused partial depolymerization of lignin mainly by cleaving the β- O -4 linkages and by demethoxylation to remove the syringyl (S) and guaiacyl (G) units. B-8 could depolymerize amount of the G units by cleaving the β-5 linkages that interconnect the lignin subunits. A biomimetic system with a biochemical Fenton reaction and lignocellulose-degrading bacteria was confirmed to be able for the pretreatment of RS to enhance enzymatic hydrolysis under mild conditions. The high digestibility was attributed to the destruction of the lignin structure, partial hydrolysis of the hemicellulose and partial surface oxidation of the cellulose. The mechanism of synergistic Fenton and B-8 pretreatment was also explored to understand the change in the RS and the bacterial effects on

  9. Remediation of a winery wastewater combining aerobic biological oxidation and electrochemical advanced oxidation processes.

    Science.gov (United States)

    Moreira, Francisca C; Boaventura, Rui A R; Brillas, Enric; Vilar, Vítor J P

    2015-05-15

    Apart from a high biodegradable fraction consisting of organic acids, sugars and alcohols, winery wastewaters exhibit a recalcitrant fraction containing high-molecular-weight compounds as polyphenols, tannins and lignins. In this context, a winery wastewater was firstly subjected to a biological oxidation to mineralize the biodegradable fraction and afterwards an electrochemical advanced oxidation process (EAOP) was applied in order to mineralize the refractory molecules or transform them into simpler ones that can be further biodegraded. The biological oxidation led to above 97% removals of dissolved organic carbon (DOC), chemical oxygen demand (COD) and 5-day biochemical oxygen demand (BOD5), but was inefficient on the degradation of a bioresistant fraction corresponding to 130 mg L(-1) of DOC, 380 mg O2 L(-1) of COD and 8.2 mg caffeic acid equivalent L(-1) of total dissolved polyphenols. Various EAOPs such as anodic oxidation with electrogenerated H2O2 (AO-H2O2), electro-Fenton (EF), UVA photoelectro-Fenton (PEF) and solar PEF (SPEF) were then applied to the recalcitrant effluent fraction using a 2.2 L lab-scale flow plant containing an electrochemical cell equipped with a boron-doped diamond (BDD) anode and a carbon-PTFE air-diffusion cathode and coupled to a photoreactor with compound parabolic collectors (CPCs). The influence of initial Fe(2+) concentration and current density on the PEF process was evaluated. The relative oxidative ability of EAOPs increased in the order AO-H2O2 < EF < PEF ≤ SPEF. The SPEF process using an initial Fe(2+) concentration of 35 mg L(-1), current density of 25 mA cm(-2), pH of 2.8 and 25 °C reached removals of 86% on DOC and 68% on COD after 240 min, regarding the biologically treated effluent, along with energy consumptions of 45 kWh (kg DOC)(-1) and 5.1 kWh m(-3). After this coupled treatment, color, odor, COD, BOD5, NH4(+), NO3(-) and SO4(2-) parameters complied with the legislation targets and, in addition, a total

  10. Acetaminophen degradation by electro-Fenton and photoelectro-Fenton using a double cathode electrochemical cell

    Energy Technology Data Exchange (ETDEWEB)

    Luna, Mark Daniel G. de [Department of Chemical Engineering, University of the Philippines, 1011 Diliman, Quezon City (Philippines); Environmental Engineering Graduate Program, University of the Philippines, 1011 Diliman, Quezon City (Philippines); Veciana, Mersabel L. [Environmental Engineering Graduate Program, University of the Philippines, 1011 Diliman, Quezon City (Philippines); Su, Chia-Chi [Department of Environmental Resources Management, Chia Nan University of Pharmacy and Science, Tainan 717, Taiwan (China); Lu, Ming-Chun, E-mail: mmclu@mail.chan.edu.tw [Department of Environmental Resources Management, Chia Nan University of Pharmacy and Science, Tainan 717, Taiwan (China)

    2012-05-30

    Highlights: Black-Right-Pointing-Pointer The electro-Fenton reactor using a double cathode electrochemical cell was applied. Black-Right-Pointing-Pointer The initial Fe{sup 2+} concentration was the most significant parameter for the acetaminophen degradation. Black-Right-Pointing-Pointer Thirteen intermediates were identified and a degradation pathway was proposed. - Abstract: Acetaminophen is a widely used drug worldwide and is one of the most frequently detected in bodies of water making it a high priority trace pollutant. This study investigated the applicability of the electro-Fenton and photoelectro-Fenton processes using a double cathode electrochemical cell in the treatment of acetaminophen containing wastewater. The Box-Behnken design was used to determine the effects of initial Fe{sup 2+} and H{sub 2}O{sub 2} concentrations and applied current density. Results showed that all parameters positively affected the degradation efficiency of acetaminophen with the initial Fe{sup 2+} concentration being the most significant parameter for both processes. The acetaminophen removal efficiency for electro-Fenton was 98% and chemical oxygen demand (COD) removal of 43% while a 97% acetaminophen removal and 42% COD removal were observed for the photoelectro-Fenton method operated at optimum conditions. The electro-Fenton process was only able to obtain 19% total organic carbon (TOC) removal while the photoelectro-Fenton process obtained 20%. Due to negligible difference between the treatment efficiencies of the two processes, the electro-Fenton method was proven to be more economically advantageous. The models obtained from the study were applicable to a wide range of acetaminophen concentrations and can be used in scale-ups. Thirteen different types of intermediates were identified and a degradation pathway was proposed.

  11. Acetaminophen degradation by electro-Fenton and photoelectro-Fenton using a double cathode electrochemical cell

    International Nuclear Information System (INIS)

    Luna, Mark Daniel G. de; Veciana, Mersabel L.; Su, Chia-Chi; Lu, Ming-Chun

    2012-01-01

    Highlights: ► The electro-Fenton reactor using a double cathode electrochemical cell was applied. ► The initial Fe 2+ concentration was the most significant parameter for the acetaminophen degradation. ► Thirteen intermediates were identified and a degradation pathway was proposed. - Abstract: Acetaminophen is a widely used drug worldwide and is one of the most frequently detected in bodies of water making it a high priority trace pollutant. This study investigated the applicability of the electro-Fenton and photoelectro-Fenton processes using a double cathode electrochemical cell in the treatment of acetaminophen containing wastewater. The Box–Behnken design was used to determine the effects of initial Fe 2+ and H 2 O 2 concentrations and applied current density. Results showed that all parameters positively affected the degradation efficiency of acetaminophen with the initial Fe 2+ concentration being the most significant parameter for both processes. The acetaminophen removal efficiency for electro-Fenton was 98% and chemical oxygen demand (COD) removal of 43% while a 97% acetaminophen removal and 42% COD removal were observed for the photoelectro-Fenton method operated at optimum conditions. The electro-Fenton process was only able to obtain 19% total organic carbon (TOC) removal while the photoelectro-Fenton process obtained 20%. Due to negligible difference between the treatment efficiencies of the two processes, the electro-Fenton method was proven to be more economically advantageous. The models obtained from the study were applicable to a wide range of acetaminophen concentrations and can be used in scale-ups. Thirteen different types of intermediates were identified and a degradation pathway was proposed.

  12. Phenol degradation by advanced Fenton process in combination with ultrasonic irradiation

    Directory of Open Access Journals (Sweden)

    F.Z. Yehia

    2015-03-01

    Full Text Available In this study, a successful degradation of phenol was achieved by means of coupling nano-sized zero-valent iron (NZVI, H2O2 and 20 kHz ultrasound irradiation. The effect of H2O2 concentration, initial pH, ultrasonic irradiation time and NZVI addition on the degradation efficiency was investigated and the kinetics of the process was discussed. The results showed that the degradation rate increased by increasing the H2O2 concentration and the irradiation time but decreased with the increase of the initial pH value. These results clearly indicate that the degradation of phenol is intensified in the presence of NZVI and H2O2, which can be attributed to enhanced production of ·−OH radicals in the system. The degradation rate in the presence of NZVI was faster than in its absence. Thus, an appropriate selection of operating conditions will lead to an economical and highly efficient technology with eventual large-scale commercial applications for the degradation of organic pollutants in aqueous effluents.

  13. Degradation of triketone herbicides, mesotrione and sulcotrione, using advanced oxidation processes

    International Nuclear Information System (INIS)

    Jović, Milica; Manojlović, Dragan; Stanković, Dalibor; Dojčinović, Biljana; Obradović, Bratislav; Gašić, Uroš; Roglić, Goran

    2013-01-01

    Highlights: • Thirteen products are identified during all degradations for both pesticides. • In all degradations same products and mechanism was observed for both pesticides. • Dominant mechanism for all degradations starts with attack on the carbonyl group. • Only in ozone and DBD degradation one product is formed in radical reaction. • Only in Fenton degradation opening of benzene ring occurs. -- Abstract: Degradation of two triketone herbicides, mesotrione and sulcotrione, was studied using four different advanced oxidation processes (AOPs): ozonization, dielectric barrier discharge (DBD reactor), photocatalysis and Fenton reagent, in order to find differences in mechanism of degradation. Degradation products were identified by high performance liquid chromatography (HPLC–DAD) and UHPLC–Orbitrap–MS analyses. A simple mechanism of degradation for different AOP was proposed. Thirteen products were identified during all degradations for both pesticides. It was assumed that the oxidation mechanisms in the all four technologies were not based only on the production and use of the hydroxyl radical, but they also included other kinds of oxidation mechanisms specific for each technology. Similarity was observed between degradation mechanism of ozonation and DBD. The greatest difference in the products was found in Fenton degradation which included the opening of benzene ring. When degraded with same AOP pesticides gave at the end of treatment the same products. Global toxicity and COD value of samples was determined after all degradations. Real water sample was used to study influence of organic matter on pesticide degradation. These results could lead to accurate estimates of the overall effects of triketone herbicides on environmental ecosystems and also contributed to the development of improved removal processes

  14. Synergistic operation of photocatalytic degradation and Fenton process by magnetic Fe3O4 loaded TiO2

    Science.gov (United States)

    Sun, Qiong; Hong, Yong; Liu, Qiuhong; Dong, Lifeng

    2018-02-01

    The magnetic Fe3O4 loaded anatase TiO2 photocatalysts with different mass ratios were successfully synthesized by a one-step convenient calcining method. The morphology and structure analysis revealed that Fe3O4 was formed in TiO2 with very fine-grained particles. After a small amount of Fe3O4 loaded onto TiO2, the photocatalytic property enhanced obviously for the degradation of organic dye. Furthermore, the photo-Fenton-like catalysis of the iron-containing samples could also be induced after the addition of hydrogen peroxide. The apparent kinetic constant of the reaction that catalyzed by Fe-TiO2 was about 5.3 and 8.3 times of that catalyzed by TiO2 or Fe3O4 only, respectively, proving an effective synergistic contribution of the photocatalysis and Fenton reaction in the composite. Compared with Fe3O4 or free Fe3+ ions, only 13% of iron in TiO2 dissolved into acidic solution (25% for Fe3O4 and 100% for Fe3+) after the reaction, which confirmed the iron had been well immobilized onto TiO2. In addition, the extremely stable photocatalytic activity in cycling experiments proved the immobilized iron had been tightly attached onto TiO2, indicating the great potential of the catalyst for practical applications.

  15. Effect of iron salt counter ion in dose-response curves for inactivation of Fusarium solani in water through solar driven Fenton-like processes

    Science.gov (United States)

    Aurioles-López, Verónica; Polo-López, M. Inmaculada; Fernández-Ibáñez, Pilar; López-Malo, Aurelio; Bandala, Erick R.

    2016-02-01

    The inactivation of Fusarium solani in water was assessed by solar driven Fenton-like processes using three different iron salts: ferric acetylacetonate (Fe(acac)3), ferric chloride (FeCl3) and ferrous sulfate (FeSO4). The experimental conditions tested were [Fe] ≈ 5 mg L-1, [H2O2] ≈ 10 mg L-1 and [Fe] ≈ 10 mg L-1; [H2O2] ≈ 20 mg L-1 mild and high, respectively, and pH 3.0 and 5.0, under solar radiation. The highest inactivation rates were observed at high reaction conditions for the three iron salts tested at pH 5.0 with less than 3.0 kJ L-1 of accumulate energy (QUV) to achieve over 99.9% of F. solani inactivation. Fe(acac)3 was the best iron salt to accomplishing F. solani inactivation. The modified Fermi equation was used to fix the experimental inactivation, data showed it was helpful for modeling the process, adequately describing dose-response curves. Inactivation process using FeSO4 at pH 3.0 was modeled fairly with r2 = 0.98 and 0.99 (mild and high concentration, respectively). Fe(acac)3, FeCl3 and FeSO4 at high concentration (i.e. [Fe] ≈ 10 mg L-1; [H2O2] ≈ 20 mg L-1) and pH 5.0 showed the highest fitting values (r2 = 0.99). Iron salt type showed a remarkable influence on the Fenton-like inactivation process.

  16. Alkaline electrochemical advanced oxidation process for chromium oxidation at graphitized multi-walled carbon nanotubes.

    Science.gov (United States)

    Xue, Yudong; Zheng, Shili; Sun, Zhi; Zhang, Yi; Jin, Wei

    2017-09-01

    Alkaline electrochemical advanced oxidation processes for chromium oxidation and Cr-contaminated waste disposal were reported in this study. The highly graphitized multi-walled carbon nanotubes g-MWCNTs modified electrode was prepared for the in-situ electrochemical generation of HO 2 - . RRDE test results illustrated that g-MWCNTs exhibited much higher two-electron oxygen reduction activity than other nanocarbon materials with peak current density of 1.24 mA cm -2 , %HO 2 - of 77.0% and onset potential of -0.15 V (vs. Hg/HgO). It was originated from the highly graphitized structure and good electrical conductivity as illustrated from the Raman, XRD and EIS characterizations, respectively. Large amount of reactive oxygen species (HO 2 - and ·OH) were in-situ electro-generated from the two-electron oxygen reduction and chromium-induced alkaline electro-Fenton-like reaction. The oxidation of Cr(III) was efficiently achieved within 90 min and the conversion ratio maintained more than 95% of the original value after stability test, offering an efficient and green approach for the utilization of Cr-containing wastes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Heterogeneous sono-Fenton-like process using martite nanocatalyst prepared by high energy planetary ball milling for treatment of a textile dye.

    Science.gov (United States)

    Dindarsafa, Mahsa; Khataee, Alireza; Kaymak, Baris; Vahid, Behrouz; Karimi, Atefeh; Rahmani, Amir

    2017-01-01

    High energy planetary ball milling was applied to prepare sono-Fenton nanocatalyst from natural martite (NM). The NM samples were milled for 2-6h at the speed of 320rpm for production of various ball milled martite (BMM) samples. The catalytic performance of the BMMs was greater than the NM for treatment of Acid Blue 92 (AB92) in heterogeneous sono-Fenton-like process. The NM and the BMM samples were characterized by XRD, FT-IR, SEM, EDX and BET analyses. The particle size distribution of the 6h-milled martite (BMM 3 ) was in the range of 10-90nm, which had the highest surface area compared to the other samples. Then, the impact of main operational parameters was investigated on the process. Complete removal of the dye was obtained at the desired conditions including initial pH 7, 2.5g/L BMM 3 dosage, 10mg/L AB92 concentration, and 150W ultrasonic power after 30min of treatment. The treatment process followed pseudo-first order kinetic. Environmentally-friendly modification of the NM, low leached iron amount and repeated application at milder pH were the significant benefits of the BMM 3 . The GC-MS was successfully used to identify the generated intermediates. Eventually, an artificial neural network (ANN) was applied to predict the AB92 removal efficiency based upon the experimental data with a proper correlation coefficient (R 2 =0.9836). Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Sistema de injeção em fluxo espectrofotométrico para monitorar peróxido de hidrogênio em processo de fotodegradação por reação foto-Fenton Flow injection spectrophotometric system for hydrogen peroxide monitoring in photo-Fenton degradation processes

    Directory of Open Access Journals (Sweden)

    Mirela C. Oliveira

    2001-04-01

    Full Text Available A flow injection spectrophotometric system was projected for monitoring hydrogen peroxide during photodegradation of organic contaminants in photo-Fenton processes (Fe2+/H2O2/UV. Sample is injected manually in a carrier stream and then receives by confluence a 0.1 mol L-1 NH4VO3 solution in 0.5 mol L-1 H2SO4 medium. The product formed shows absorption at 446 nm which is recorded as a peak with height proportional to H2O2 concentration. The performance of the proposed system was evaluated by monitoring the consumption of H2O2 during the photodegradation of dichloroacetic acid solution by foto-Fenton reaction.

  19. Optimizing the solar photo-Fenton process in the treatment of contaminated water. Determination of intrinsic kinetic constants for scale-up

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Miguel [Universidad de Los Andes, Escuela Basica de Ingenieria, La Hechicera, Merida (Venezuela); Malato, Sixto [Plataforma Solar de Almeria, Tabernas (PSA) (Spain); Pulgarin, Cesar [Institute of Environmental Engineering, Laboratory for Environmental Biotechnology, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne (Switzerland); Contreras, Sandra; Curco, David; Gimenez, Jaime; Esplugas, Santiago [Department d' Enginyeria Quimica i Metallurgia, Universitat de Barcelona, Marti i Franques 1, 08028 Barcelona (Spain)

    2005-10-01

    The elimination of aromatic compounds present in surface water by photo-Fenton with sunlight as the source of radiation was studied. The concentrations of Fe{sup 3+} and H{sub 2}O{sub 2} are key factors for this process. A solar simulator and a prototype parabolic collector were used as laboratory-scale reactors to find the parameters of those key factors to be used in the CPC (compound parabolic collector) pilot plant reactor. The initial mineralization rate constant (k{sub obs}) was determined and evaluated at different Fe{sup 3+} and H{sub 2}O{sub 2} concentrations to find the best values for maximum efficiency. In all the experiments the mineralization of an aqueous phenol solution was described by assuming a pseudo-first-order reaction. The intrinsic kinetic constants not dependent on the lighting conditions were also estimated for scale-up. (author)

  20. Efficient degradation of phenol using iron-montmorillonite as a Fenton catalyst: Importance of visible light irradiation and intermediates

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Xipeng; Wu, Honghai, E-mail: wuhonghai@scnu.edu.cn; He, Guangping, E-mail: hegp@scnu.edu.cn; Guan, Yufeng

    2017-01-05

    Highlights: • Iron-montmorillonite has excellent catalytic activity on phenol Fenton degradation. • Phenol Fenton reaction follows the two-stage pseudo first order kinetic equations. • Role of visible light irradiation is more evident during induction reaction period. • Hydroquinone and catechol have a significant effect on the second-stage kinetics. - Abstract: Iron-montmorillonite (Fe-Mt) with delaminated structures was synthesized via the introduction of iron oxides into Na-montmorillonite. Fe-Mt showed significant increases in the available iron content, surface area and pore volume, along with a slight increase in the basal spacing from d{sub 001} = 1.26 (Na-Mt) to 1.53 nm (Fe-Mt). The Fenton process was efficient for phenol removal using Fe-Mt as a catalyst under visible light irradiation, and the process had two-stage pseudo-first order kinetics. The overall reaction had a higher degradation rate even when it was only irradiated with visible light for the first 40 min period. Further investigation confirmed that the irradiation increased the presence of certain intermediates. Among them, 1,4-benzoquinone, hydroquinone, and catechol all enhanced the Fenton reaction rates. Either catechol or hydroquinone was added to the Fenton system with Fe-Mt/H{sub 2}O{sub 2} with or without visible light irradiation, and they both accelerated phenol degradation because catechol and hydroquinone are capable of reductively and effectively transforming Fe(III) into Fe(II). The concentrations of dissolved total Fe increased with the increase in the oxalic acid concentration, which can strongly chelate Fe(III). Hence, iron was released from Fe-Mt, and reductive transformation played an important role in promoting the Fenton reaction process for phenol removal.

  1. Efficient degradation of phenol using iron-montmorillonite as a Fenton catalyst: Importance of visible light irradiation and intermediates

    International Nuclear Information System (INIS)

    Wei, Xipeng; Wu, Honghai; He, Guangping; Guan, Yufeng

    2017-01-01

    Highlights: • Iron-montmorillonite has excellent catalytic activity on phenol Fenton degradation. • Phenol Fenton reaction follows the two-stage pseudo first order kinetic equations. • Role of visible light irradiation is more evident during induction reaction period. • Hydroquinone and catechol have a significant effect on the second-stage kinetics. - Abstract: Iron-montmorillonite (Fe-Mt) with delaminated structures was synthesized via the introduction of iron oxides into Na-montmorillonite. Fe-Mt showed significant increases in the available iron content, surface area and pore volume, along with a slight increase in the basal spacing from d_0_0_1 = 1.26 (Na-Mt) to 1.53 nm (Fe-Mt). The Fenton process was efficient for phenol removal using Fe-Mt as a catalyst under visible light irradiation, and the process had two-stage pseudo-first order kinetics. The overall reaction had a higher degradation rate even when it was only irradiated with visible light for the first 40 min period. Further investigation confirmed that the irradiation increased the presence of certain intermediates. Among them, 1,4-benzoquinone, hydroquinone, and catechol all enhanced the Fenton reaction rates. Either catechol or hydroquinone was added to the Fenton system with Fe-Mt/H_2O_2 with or without visible light irradiation, and they both accelerated phenol degradation because catechol and hydroquinone are capable of reductively and effectively transforming Fe(III) into Fe(II). The concentrations of dissolved total Fe increased with the increase in the oxalic acid concentration, which can strongly chelate Fe(III). Hence, iron was released from Fe-Mt, and reductive transformation played an important role in promoting the Fenton reaction process for phenol removal.

  2. Micropollutant degradation, bacterial inactivation and regrowth risk in wastewater effluents: Influence of the secondary (pre)treatment on the efficiency of Advanced Oxidation Processes.

    Science.gov (United States)

    Giannakis, Stefanos; Voumard, Margaux; Grandjean, Dominique; Magnet, Anoys; De Alencastro, Luiz Felippe; Pulgarin, César

    2016-10-01

    In this work, disinfection by 5 Advanced Oxidation Processes was preceded by 3 different secondary treatment systems present in the wastewater treatment plant of Vidy, Lausanne (Switzerland). 5 AOPs after two biological treatment methods (conventional activated sludge and moving bed bioreactor) and a physiochemical process (coagulation-flocculation) were tested in laboratory scale. The dependence among AOPs efficiency and secondary (pre)treatment was estimated by following the bacterial concentration i) before secondary treatment, ii) after the different secondary treatment methods and iii) after the various AOPs. Disinfection and post-treatment bacterial regrowth were the evaluation indicators. The order of efficiency was Moving Bed Bioreactor > Activated Sludge > Coagulation-Flocculation > Primary Treatment. As far as the different AOPs are concerned, the disinfection kinetics were: UVC/H2O2 > UVC and solar photo-Fenton > Fenton or solar light. The contextualization and parallel study of microorganisms with the micropollutants of the effluents revealed that higher exposure times were necessary for complete degradation compared to microorganisms for the UV-based processes and inversed for the Fenton-related ones. Nevertheless, in the Fenton-related systems, the nominal 80% removal of micropollutants deriving from the Swiss legislation, often took place before the elimination of bacterial regrowth risk. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Ferrocene-catalyzed heterogeneous Fenton-like degradation mechanisms and pathways of antibiotics under simulated sunlight: A case study of sulfamethoxazole.

    Science.gov (United States)

    Li, Yingjie; Zhang, Biaojun; Liu, Xiangliang; Zhao, Qun; Zhang, Heming; Zhang, Yuechao; Ning, Ping; Tian, Senlin

    2018-07-05

    Readily-available and efficient catalyst is essential for activating oxidants to produce reactive species for deeply remediating water bodies contaminated by antibiotics. In this study, Ferrocene (Fc) was introduced to establish a heterogeneous photo-Fenton system for the degradation of sulfonamide antibiotics, taking sulfamethoxazole as a representative. Results showed that the removal of sulfamethoxazole was effective in Fc-catalyzed photo-Fenton system. Electron spin resonance and radical scavenging experiments verified that there was a photoindued electron transfer process from Fc to H 2 O 2 and dissolved oxygen resulting in the formation of OH that was primarily responsible for the degradation of sulfamethoxazole. The reactions of OH with substructure model compounds of sulfamethoxazole unveiled that aniline moiety was the preferable reaction site of sulfamethoxazole, which was verified by the formation of hydroxylated product and the dimer of sulfamethoxazole in Fc-catalyzed photo-Fenton system. This heterogeneous photo-Fenton system displayed an effective degradation efficiency even in a complex water matrices, and Fc represented a long-term stability by using the catalyst for multiple cycles. These results demonstrate that Fc-catalyzed photo-Fenton oxidation may be an efficient approach for remediation of wastewater containing antibiotics. Copyright © 2018. Published by Elsevier B.V.

  4. Degradation mechanism of Direct Pink 12B treated by iron-carbon micro-electrolysis and Fenton reaction.

    Science.gov (United States)

    Wang, Xiquan; Gong, Xiaokang; Zhang, Qiuxia; Du, Haijuan

    2013-12-01

    The Direct Pink 12B dye was treated by iron-carbon micro-electrolysis (ICME) and Fenton oxidation. The degradation pathway of Direct Pink 12B dye was inferred by ultraviolet visible (UV-Vis), infrared absorption spectrum (IR) and high performance liquid chromatography-mass spectrometry (HPLC-MS). The major reason of decolorization was that the conjugate structure was disrupted in the iron-carbon micro-electrolysis (ICME) process. However, the dye was not degraded completely because benzene rings and naphthalene rings were not broken. In the Fenton oxidation process, the azo bond groups surrounded by higher electron cloud density were first attacked by hydroxyl radicals to decolorize the dye molecule. Finally benzene rings and naphthalene rings were mineralized to H2O and CO2 under the oxidation of hydroxyl radicals. Copyright © 2013 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  5. A microbial electro-fenton cell for removing carbamazepine in wastewater with electricity output.

    Science.gov (United States)

    Wang, Wei; Lu, Yaobin; Luo, Haiping; Liu, Guangli; Zhang, Renduo; Jin, Song

    2018-03-27

    High electrical energy is required for the electro-Fenton process to remove pharmaceuticals and personal care products (PPCPs) in wastewater. The aim of this study was to develop a novel and more cost-effective process, specifically a microbial electro-Fenton cell (MeFC), for treating PPCPs in wastewater. Acetylene black was selected as the catalyst for H 2 O 2 electrogeneration and Fe-Mn binary oxide for hydroxyl radical production. In addition to lowering energy needs, the MeFC produced a maximum power density of 112 ± 11 mW/m 2 with 1 g/L acetate as a representative substrate and 10 mg/L carbamazepine (CBZ) as a typical PPCP. Comparing with electro-Fenton process, the CBZ removal in the MeFC was 38% higher within 24 h operation (90% vs. 62%). Furthermore, the CBZ removal rate in the MeFC was 10-100 times faster than that in other biological treatment processes. Such enhanced degradation of CBZ in the MeFC was attributed to the synergistic reactions between radical oxidation of CBZ and biodegradation of degradative intermediates. The MeFC provides a promising method to remove PPCPs from wastewater coupling with efficient removal of other biodegradable organics. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Reactivity of catecholamine-driven Fenton reaction and its relationships with iron(III) speciation.

    Science.gov (United States)

    Melin, Victoria; Henríquez, Adolfo; Freer, Juanita; Contreras, David

    2015-03-01

    Fenton reaction is the main source of free radicals in biological systems. The reactivity of this reaction can be modified by several factors, among these iron ligands are important. Catecholamine (dopamine, epinephrine, and norepinephrine) are able to form Fe(III) complexes whose extension in the coordination number depends upon the pH. Fe(III)-catecholamine complexes have been related with the development of several pathologies. In this work, the ability of catecholamines to enhance the oxidative degradation of an organic substrate (veratryl alcohol, VA) through Fenton and Fenton-like reactions was studied. The initial VA degradation rate at different pH values and its relationship to the different iron species present in solution were determined. Furthermore, the oxidative degradation of VA after 24 hours of reaction and its main oxidation products were also determined. The catecholamine-driven Fenton and Fenton-like systems showed higher VA degradation compared to unmodified Fenton or Fenton-like systems, which also showed an increase in the oxidation state of the VA degradation product. All of this oxidative degradation takes place at pH values lower than 5.50, where the primarily responsible species would be the Fe(III) mono-complex. The presence of Fe(III) mono-complex is essential in the ability of catecholamines to increase the oxidative capacity of Fenton systems.

  7. Effects of UV irradiation on humic acid removal by ozonation, Fenton and Fe0/air treatment: THMFP and biotoxicity evaluation

    International Nuclear Information System (INIS)

    Wei, Ming-Chi; Wang, Kai-sung; Hsiao, Tung-En; Lin, I.-Chen; Wu, Hui-Ju; Wu, Yuh-Luan; Liu, Pey-Horng; Chang, Shih-Hsien

    2011-01-01

    Highlights: → Fe 0 /air rapidly and effectively removed HA within 9 min and its COD, biotoxicity and THMFP were low. → THMFP of ozonation-treated solution was much higher than those of Fenton-treated and Fe 0 /air-treated solutions. → UV irradiation during ozonation and Fenton oxidation enhanced HA removal, but did not reduce the THMFP of the treated solutions. → Fe 0 /air treatment with UV irradiation obviously increased the THMFP of the treated solution. → The relationship between biotoxicity and chloroform in the chlorinated solution was insignificant. - Abstract: Effects of UV irradiation on humic acid (HA) removal by Fe 0 /air, ozonation and Fenton oxidation were investigated. The trihalomethane forming potential (THMFP) and toxicity of treated solutions were also evaluated. The experimental conditions were ozone of 21 mg min -1 , H 2 O 2 of 8 x 10 -4 M, Fe 0 of 20 g L -1 , air flow of 5 L min -1 , and UVC of 9 W. Results indicated that Fe 0 /air rapidly removed HA color (>99%) and COD (90%) within 9 min. 51-81% of color and 43-50% of COD were removed by ozonation and Fenton oxidation after 60 min. Both UV enhanced ozone and Fenton oxidation removed HA, but the Fe 0 /air process did not. Spectrum results showed all processes effectively diminished UV-vis spectra, except for ozonation. The THMFP of Fe 0 /air-treated solution (114 μg L -1 ) was much lower than those of Fenton- (226 μg L -1 ) and ozonation-treated solutions (499 μg L -1 ). Fe 0 /air with UV irradiation obviously increased the THMFP of treated solution (502 μg L -1 ). The toxicity results obtained from Vibrio fischeri light inhibition test indicated that the toxicity of Fe 0 /air-treated solution (5%) was much lower than that of ozonation- (33%) and Fenton-treated solutions (31%). Chlorination increased the solution toxicity. The correlation between biotoxicity and chloroform in the chlorinated solution was insignificant.

  8. Effective degradation of rhodamine B by electro-Fenton process, using ferromagnetic nanoparticles loaded on modified graphite felt electrode as reusable catalyst: in neutral pH condition and without external aeration.

    Science.gov (United States)

    Tian, Jiangnan; Zhao, Jixiang; Olajuyin, Ayobami Matthew; Sharshar, Moustafa Mohamed; Mu, Tingzhen; Yang, Maohua; Xing, Jianmin

    2016-08-01

    Polytetrafluoroethylene/ferromagnetic nanoparticle/carbon black (PTFE/MNP/CB)-modified graphite felt (GF) was successfully applied as cathode for the mineralization of rhodamine B (RhB) in electro-Fenton (EF) process. The modified cathode showed high decolorization efficiency for RhB solution even in neutral pH condition and without external aeration, achieving nearly complete decolorization and 89.52 % total organic carbon (TOC) removal after 270-min oxidation with the MNP load 1.2 g at 50 A/m(2). Moreover, the operational parameters (current density, MNP load, initial pH, and airflow rate) were optimized. After that, adsorption isotherm was also conducted to compare the absorption quantity of CB and carbon nanotube (CNT). Then, the surface morphologies of MNPs were characterized by transmission electron microscope (TEM), energy-dispersive X-ray detector (EDX), and Fourier transform infrared spectroscopy (FTIR); and the modified cathode was characterized by SEM and contact angle. Finally, the stability and reusability of modified cathode were tested. Result uncovered that the PTFE/MNP/CB-modified cathode has the potential for industrial application and the solution after treatment was easily biodegradable.

  9. Advanced Heterogeneous Fenton Treatment of Coalbed Methane-Produced Water Containing Fracturing Fluid

    Directory of Open Access Journals (Sweden)

    Meng Zhang

    2018-04-01

    Full Text Available This study investigated the heterogeneous Fenton treatment to process coalbed methane-produced water containing fracturing fluid and chose the development region of coalbed methane in the Southern Qinshui Basin as a research area. We synthesized the catalyst of Fe-Co/γ-Al2O3 by homogeneous precipitation method and characterized it by BET, XRD, SEM-EDS, FTIR, and XPS. Based on the degradation rate, we studied the influences of the heterogeneous Fenton method on the coalbed methane output water treatment process parameters, including initial pH, H2O2 concentration, and the catalyst concentration. We also investigated the impacts of overall reaction kinetics of heterogeneous catalytic oxidation on coalbed methane-produced water containing fracturing fluid. Results showed that Fe-Co/γ-Al2O3 as a Fenton catalyst has a good catalytic oxidation effect and can effectively process coalbed methane-produced water. This reaction also followed first-order kinetics. The optimal conditions were as follows: the initial pH of 3.5, a H2O2 concentration of 40 mol L−1, a catalyst concentration of 4 g/L, and an apparent reaction rate constant of 0.0172 min−1. Our results provided a basis to establish methods for treating coalbed methane-produced water.

  10. Pyrite nanoparticles as a Fenton-like reagent for in situ remediation of organic pollutants

    Directory of Open Access Journals (Sweden)

    Carolina Gil-Lozano

    2014-06-01

    Full Text Available The Fenton reaction is the most widely used advanced oxidation process (AOP for wastewater treatment. This study reports on the use of pyrite nanoparticles and microparticles as Fenton reagents for the oxidative degradation of copper phthalocyanine (CuPc as a representative contaminant. Upon oxidative dissolution in water, pyrite (FeS2 particles can generate H2O2 at their surface while simultaneously promoting recycling of Fe3+ into Fe2+ and vice versa. Pyrite nanoparticles were synthesized by the hot injection method. The use of a high concentration of precursors gave individual nanoparticles (diameter: 20 nm with broader crystallinity at the outer interfaces, providing a greater number of surface defects, which is advantageous for generating H2O2. Batch reactions were run to monitor the kinetics of CuPc degradation in real time and the amount of H2O2. A markedly greater degradation of CuPc was achieved with nanoparticles as compared to microparticles: at low loadings (0.08 mg/L and 20 h reaction time, the former enabled 60% CuPc removal, whereas the latter enabled only 7% removal. These results confirm that the use of low concentrations of synthetic nanoparticles can be a cost effective alternative to conventional Fenton procedures for use in wastewater treatment, avoiding the potential risks caused by the release of heavy metals upon dissolution of natural pyrites.

  11. Enhanced Fenton-like removal of nitrobenzene via internal microelectrolysis in nano zerovalent iron/activated carbon composite.

    Science.gov (United States)

    Hu, Sihai; Wu, Yaoguo; Yao, Hairui; Lu, Cong; Zhang, Chengjun

    2016-01-01

    The efficiency of Fenton-like catalysis using nano zerovalent iron (nZVI) is limited by nZVI aggregation and activity loss due to inactive ferric oxide forming on the nZVI surface, which hinders electron transfer. A novel iron-carbon composite catalyst consisting of nZVI and granular activated carbon (GAC), which can undergo internal iron-carbon microelectrolysis spontaneously, was successfully fabricated by the adsorption-reduction method. The catalyst efficiency was evaluated in nitrobenzene (NB) removal via the Fenton-like process (H2O2-nZVI/GAC). The results showed that nZVI/GAC composite was good for dispersing nZVI on the surface of GAC, which permitted much better removal efficiency (93.0%) than nZVI (31.0%) or GAC (20.0%) alone. Moreover, iron leaching decreased from 1.28 to 0.58 mg/L after reaction of 240 min and the oxidation kinetic of the Fenton-like reaction can be described well by the second-order reaction kinetic model (R2=0.988). The composite catalyst showed sustainable catalytic ability and GAC performed as a medium for electron transfer in internal iron-carbon microelectrolysis to promote Fe2+ regeneration and Fe3+/Fe2+ cycles. Therefore, this study represents an important method to design a low cost and high efficiency Fenton-like catalyst in practical application.

  12. Roles of iron species and pH optimization on sewage sludge conditioning with Fenton's reagent and lime.

    Science.gov (United States)

    Yu, Wenbo; Yang, Jiakuan; Shi, Yafei; Song, Jian; Shi, Yao; Xiao, Jun; Li, Chao; Xu, Xinyu; He, Shu; Liang, Sha; Wu, Xu; Hu, Jingping

    2016-05-15

    Conditioning sewage sludge with Fenton's reagent could effectively improve its dewaterability. However, drawbacks of conditioning with Fenton's reagent are requirement of acidic conditions to prevent iron precipitation and subsequent neutralization with alkaline additive to obtain the pH of the filtrate close to neutrality. In this study, roles of pH were thoroughly investigated in the acidification pretreatment, Fenton reaction, and the final filtrate after conditioning. Through the response surface methodology (RSM), the optimal dosages of H2SO4, Fe(2+), H2O2, and lime acted as a neutralizer were found to be 0 (no acidification), 47.9, 34.3 and 43.2 mg/g DS (dry solids). With those optimal doses, water content of the dewatered sludge cakes could be reduced to 55.8 ± 0.6 wt%, and pH of the final filtrate was 6.6 ± 0.2. Fenton conditioning without initial acidification can simplify the conditioning process and reduce the usage of lime. The Fe(3+) content in the sludge cakes showed a close correlation with the dewaterability of conditioned sludge, i.e., the water content of sludge cakes, SRF (specific resistance to filtration), CST (capillary suction time), bound water content, and specific surface area. It indicated that the coagulation by Fe(3+) species in Fenton reaction could play an important role, compared to traditional Fenton oxidation effect on sludge conditioning. Thus, a two-step mechanism of Fenton oxidation and Fe(III) coagulation was proposed in sewage sludge conditioning. The mechanisms include the following: (1) extracellular polymeric substances (EPS) were firstly degraded into dissolved organics by Fenton oxidation; (2) bound water was converted to free water due to degradation of EPS; (3) the sludge particles were disintegrated into small ones by oxidation; (4) Fe(3+) generated from Fenton reaction acted as a coagulant to agglomerate smaller sludge particles into larger dense particles with less bond water; (5) finally, the dewatered

  13. Fenton- and Persulfate-driven Regeneration of Contaminant-spent Granular Activated Carbon

    Science.gov (United States)

    Fenton- or persulfate-driven chemical oxidation regeneration of spent granular activated carbon (GAC) involves the combined, synergistic use of two treatment technologies: adsorption of organic chemicals onto GAC and chemical oxidation regeneration of the spent-GAC. Environmental...

  14. Effect of a solar Fered-Fenton system using a recirculation reactor on biologically treated landfill leachate.

    Science.gov (United States)

    Ye, Zhihong; Zhang, Hui; Yang, Lin; Wu, Luxue; Qian, Yue; Geng, Jinyao; Chen, Mengmeng

    2016-12-05

    The effects of electrochemical oxidation (EO), Fered-Fenton and solar Fered-Fenton processes using a recirculation flow system containing an electrochemical cell and a solar photo-reactor on biochemically treated landfill leachate were investigated. The most successful method was solar Fered-Fenton which achieved 66.5% COD removal after 120min treatment utilizing the optimum operating conditions of 47mM H2O2, 0.29mM Fe(2+), pH0 of 3.0 and a current density of 60mA/cm(2). The generation of hydroxyl radicals (OH) are mainly from Fered-Fenton process, which is enhanced by the introduction of renewable solar energy. Moreover, Fe(2+)/chlorine and UV/chlorine processes taking place in this system also result in additional production of OH due to the relatively high concentration of chloride ions contained in the leachate. The energy consumption was 74.5kWh/kg COD and the current efficiency was 36.4% for 2h treatment. In addition, the molecular weight (MW) distribution analysis and PARAFAC analysis of excitation emission matrix (EEM) fluorescence spectroscopy for different leachate samples indicated that the organics in the leachate were significantly degraded into either small molecular weight species or inorganics. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Performance Evaluation of Electro-Fenton Process (EFP in Removal of Hexavalent Chromium in the Presence of Cyanide, as an Interfering Agent, from Synthetic Wastewaters

    Directory of Open Access Journals (Sweden)

    Ali Reza Rahmani

    2014-06-01

    Full Text Available Background: Chromium (VI is a hazardous pollutant that enters into the environment through different industrial wastewater. Therefore, Choice a suitable method for removal of the pollutant before discharging into the environment is necessary. The aim of this work was performance evaluation of Electro-Fenton process (EFP in removal of hexavalent chromium in the presence of cyanide, as an interfering agent, from synthetic wastewaters. Methods: In this experimental study, a reactor with 1 L useful volume and 4 electrodes made ​​of iron was used. pH, initial concentration of  chromium (VI, voltage, hydrogen peroxide and cyanide concentration, as an interfering agent, were investigated in order to determine the process efficiency. Results: Results reveals that the considered parameters were affected on the efficiency of the process. In optimum condition, pH=3 and voltage=20 V, initial concentration=100 mg/L, concentration of hydrogen peroxide=50 mL/L the maximum efficiency was reached up to 97%. Cyanide Presence, in the same condition, reduced the efficiency under 50 % and also, the efficiency was decreased by changing the parameters level from optimum condition. Conclusion: Results indicate the proper efficiency of chromium (VI by EFP process; however presence of other pollutants such as cyanide can cause efficiency decrease which must be considered in the process application.

  16. Effect of pH and H2O2 dosage on catechol oxidation in nano-Fe3O4 catalyzing UV-Fenton and identification of reactive oxygen species

    DEFF Research Database (Denmark)

    Li, Weiguang; Wang, Yong; Angelidaki, Irini

    2014-01-01

    and then increased, which was ascribed to the formation and destruction of some carboxylic acids. During the degradation, formic acid, acetic acid, oxalic acid, and maleic acid were detected. The values of H2O2 utilization efficiency at 240min near 1.30 in reactions with 11.80mM H2O2 under initial pH from 5.0 to 8.......0-8.0), this heterogeneous UV-Fenton process was powerful, especially reaction at pH 7.0 obtaining the highest COD removal of 93%. The remarkably high oxidation efficiency under neutral and slightly basic conditions was due to fast decrease of solution pH to be strongly acidic. Solution pH decreased until 120min...

  17. Electrocatalytic properties of N-doped graphite felt in electro-Fenton process and degradation mechanism of levofloxacin.

    Science.gov (United States)

    Liu, Xiaocheng; Yang, Danxing; Zhou, Yaoyu; Zhang, Jiachao; Luo, Lin; Meng, Sijun; Chen, Song; Tan, Mengjiao; Li, Zhicheng; Tang, Lin

    2017-09-01

    The degradation of antibiotic levofloxacin was investigated by dimensionally stable anode as well as modified cathode using low-cost chemical reagents of hydrazine hydrate and ethanol for electro-Fenton in an undivided cell at pH 3.0 under room temperature. Comparison of unmodified and modified cathode was performed. The apparent rate constant of levofloxacin decay was found to be 0.2883 min -1 for graphite felt-10 with the best performance at 200 mA, which is lower than graphite felt at 400 mA. The optimum modified cathode showed a significant improvement of complete mineralization of levofloxacin, reaching a 92% TOC removal at 200 mA for 480 min higher than unmodified one at twice the current. Surface physicochemical properties and morphology were investigated by scanning electron microscope, contact angle and X-ray photoelectron spectroscopy. The electrochemical characterization of hydrogen evolution reaction was adopted to clarify a possible pathway for the higher mineralization of levofloxacin, indicating a potential pilot-scale study to the pollution with the similar structure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Bifunctional composite from spent "Cyprus coffee" for tetracycline removal and phenol degradation: Solar-Fenton process and artificial neural network.

    Science.gov (United States)

    Oladipo, Akeem Adeyemi; Abureesh, Mosab Ali; Gazi, Mustafa

    2016-09-01

    Removals of tetracycline and photocatalytic degradation of phenol by Fe3O4/coffee residue (MCC) were investigated. Brunauer-Emmett-Teller (BET), vibrating sample magnetometer (VSM) and Boehm titration were employed to characterize MCC. Artificial neural network (ANN) model was developed to predict the tetracycline (TC) concentration in the column effluent. Maximum tetracycline adsorption capacity of 285.6mg/g was observed in a batch system. High removal efficiency (87%) was obtained at 3.3mL/min flow rate, 8.0cm bed height and 50mg/L influent TC concentration in a column system. Complete degradation of phenol by solar-Fenton was attained at 60min irradiation time. Total organic carbon (TOC) removal increased to 63.3% in the presence of 1.0g/L MCC, 1.2g/L H2O2 and solar irradiation. MCC showed remarkable potential to remove antibiotics from wastewater even in the presence of heavy metal (Ni(2+)) via magnetic separation. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Interfacial mechanisms of heterogeneous Fenton reactions catalyzed by iron-based materials: A review.

    Science.gov (United States)

    He, Jie; Yang, Xiaofang; Men, Bin; Wang, Dongsheng

    2016-01-01

    The heterogeneous Fenton reaction can generate highly reactive hydroxyl radicals (OH) from reactions between recyclable solid catalysts and H2O2 at acidic or even circumneutral pH. Hence, it can effectively oxidize refractory organics in water or soils and has become a promising environmentally friendly treatment technology. Due to the complex reaction system, the mechanism behind heterogeneous Fenton reactions remains unresolved but fascinating, and is crucial for understanding Fenton chemistry and the development and application of efficient heterogeneous Fenton technologies. Iron-based materials usually possess high catalytic activity, low cost, negligible toxicity and easy recovery, and are a superior type of heterogeneous Fenton catalysts. Therefore, this article reviews the fundamental but important interfacial mechanisms of heterogeneous Fenton reactions catalyzed by iron-based materials. OH, hydroperoxyl radicals/superoxide anions (HO2/O2(-)) and high-valent iron are the three main types of reactive oxygen species (ROS), with different oxidation reactivity and selectivity. Based on the mechanisms of ROS generation, the interfacial mechanisms of heterogeneous Fenton systems can be classified as the homogeneous Fenton mechanism induced by surface-leached iron, the heterogeneous catalysis mechanism, and the heterogeneous reaction-induced homogeneous mechanism. Different heterogeneous Fenton systems catalyzed by characteristic iron-based materials are comprehensively reviewed. Finally, related future research directions are also suggested. Copyright © 2015. Published by Elsevier B.V.

  20. Optimization of the electro-Fenton and solar photoelectro-Fenton treatments of sulfanilic acid solutions using a pre-pilot flow plant by response surface methodology

    International Nuclear Information System (INIS)

    El-Ghenymy, Abdellatif; Garcia-Segura, Sergi; Rodríguez, Rosa María; Brillas, Enric; El Begrani, Mohamed Soussi; Abdelouahid, Ben Ali

    2012-01-01

    Highlights: ► Quicker degradation of sulfanilic acid by solar photoelectro-Fenton than electro-Fenton. ► The same optimized current density, Fe 2+ content and pH for both processes by CCRD. ► Description of TOC, energy cost and current efficiency by response surface methodology. ► Fe(III)–carboxylate complexes as main by-products after electro-Fenton. ► Photolysis of these complexes by UV irradiation of sunlight in solar photoelectro-Fenton. - Abstract: A central composite rotatable design and response surface methodology were used to optimize the experimental variables of the electro-Fenton (EF) and solar photoelectro-Fenton (SPEF) degradations of 2.5 L of sulfanilic acid solutions in 0.05 M Na 2 SO 4 . Electrolyses were performed with a pre-pilot flow plant containing a Pt/air diffusion reactor generating H 2 O 2 . In SPEF, it was coupled with a solar photoreactor under an UV irradiation intensity of ca. 31 W m −2 . Optimum variables of 100 mA cm −2 , 0.5 mM Fe 2+ and pH 4.0 were determined after 240 min of EF and 120 min of SPEF. Under these conditions, EF gave 47% of mineralization, whereas SPEF was much more powerful yielding 76% mineralization with 275 kWh kg −1 total organic carbon (TOC) energy consumption and 52% current efficiency. Sulfanilic acid decayed at similar rate in both treatments following a pseudo-first-order kinetics. The final solution treated by EF contained a stable mixture of tartaric, acetic, oxalic and oxamic acids, which form Fe(III) complexes that are not attacked by hydroxyl radicals formed from H 2 O 2 and added Fe 2+ . The quick photolysis of these complexes by UV light of sunlight explains the higher oxidation power of SPEF. NH 4 + was the main inorganic nitrogen ion released in both processes.

  1. Particle Size Effects on Fenton Regeneration of MTBE-spent Activated Carbon

    Science.gov (United States)

    Fenton-driven regeneration of spent granular activated carbon (GAC) is a developing technology that may reduce water treatment costs. In this study, the effect of GAC particle size on Fenton-driven oxidation of methyl tert-butyl ether (MTBE)-spent GAC was evaluated. The GAC was...

  2. Fenton-Driven Regeneration of MTBE-spent Granular Activated Carbon

    Science.gov (United States)

    Fenton-driven regeneration of Methyl tert-butyl ether (MTBE)-spent granular activated carbon (GAC) involves the combined, synergistic use of two treatment technologies: adsorption of organic chemicals onto activated carbon and Fenton-driven oxidation regeneration of the spent-GAC...

  3. Degradation of Procion Red H-E7B reactive dye by coupling a photo-Fenton system with a sequencing batch reactor

    International Nuclear Information System (INIS)

    Garcia-Montano, Julia; Torrades, Francesc; Garcia-Hortal, Jose A.; Domenech, Xavier; Peral, Jose

    2006-01-01

    A bench-scale study combining photo-Fenton reaction with an aerobic sequencing batch reactor (SBR) to degrade a commercial homo-bireactive dye (Procion Red H-E7B, 250 mg l -1 ) was investigated. The photo-Fenton process was applied as a pre-treatment, avoiding complete mineralisation, just to obtain a bio-compatible water able to be treated by means of the SBR in a second step. In this sense, different Fenton reagent concentrations were assessed by following dye solution biodegradability enhancement (BOD 5 /COD), as well as the toxicity (EC 50 ), DOC, colour (Abs 543.5 ) and H 2 O 2 evolution with photo-Fenton irradiation time. Obtained pre-treated solutions were biologically oxidized in a SBR containing non-acclimated activated sludge. Different hydraulic retention time (HRT) in the bioreactor were tested to attain the maximum organic load removal efficiency. Best results were obtained with 60 min of 10 mg l -1 Fe(II) and 125 mg l -1 H 2 O 2 photo-Fenton pre-treatment and 1 day HRT in SBR

  4. Degradation of Procion Red H-E7B reactive dye by coupling a photo-Fenton system with a sequencing batch reactor

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Montano, Julia [Departament de Quimica, Edifici Cn, Universitat Autonoma de Barcelona, E-08193 Bellaterra, Barcelona (Spain); Torrades, Francesc [Departament d' Enginyeria Quimica, ETSEI de Terrassa (UPC), C/Colom, 11, E-08222 Terrassa, Barcelona (Spain); Garcia-Hortal, Jose A. [Departament d' Enginyeria Textil i Paperera, ETSEI de Terrassa (UPC), C/Colom, 11, E-08222 Terrassa, Barcelona (Spain); Domenech, Xavier [Departament de Quimica, Edifici Cn, Universitat Autonoma de Barcelona, E-08193 Bellaterra, Barcelona (Spain); Peral, Jose [Departament de Quimica, Edifici Cn, Universitat Autonoma de Barcelona, E-08193 Bellaterra, Barcelona (Spain)]. E-mail: jose.peral@uab.es

    2006-06-30

    A bench-scale study combining photo-Fenton reaction with an aerobic sequencing batch reactor (SBR) to degrade a commercial homo-bireactive dye (Procion Red H-E7B, 250 mg l{sup -1}) was investigated. The photo-Fenton process was applied as a pre-treatment, avoiding complete mineralisation, just to obtain a bio-compatible water able to be treated by means of the SBR in a second step. In this sense, different Fenton reagent concentrations were assessed by following dye solution biodegradability enhancement (BOD{sub 5}/COD), as well as the toxicity (EC{sub 50}), DOC, colour (Abs{sub 543.5}) and H{sub 2}O{sub 2} evolution with photo-Fenton irradiation time. Obtained pre-treated solutions were biologically oxidized in a SBR containing non-acclimated activated sludge. Different hydraulic retention time (HRT) in the bioreactor were tested to attain the maximum organic load removal efficiency. Best results were obtained with 60 min of 10 mg l{sup -1} Fe(II) and 125 mg l{sup -1} H{sub 2}O{sub 2} photo-Fenton pre-treatment and 1 day HRT in SBR.

  5. Pengolahan Limbah Cair Pabrik Pupuk Urea Menggunakan Advanced Oxidation Processes

    Directory of Open Access Journals (Sweden)

    Darmadi Darmadi

    2014-06-01

    Full Text Available Limbah cair pabrik pupuk urea terdiri dari urea dan amonium yang masing-masing mempunyai konsentrasi berkisar antara 1500-10000 ppm dan 400-3000 ppm. Konsentrasi urea yang tinggi di dalam badan air dapat menyebabkan blooming algae dalam ekosistem tersebut yang dapat mengakibatkan kehidupan biota air lain terserang penyakit. Peristiwa ini terjadi karena kurangnya nutrisi bagi biota air dan sedikitnya sinar matahari yang dapat menembusi permukaan air. Disamping kedua hal tersebut di atas, algae juga dapat memproduksi senyawa beracun bagi biota air dan manusia. Penelitian ini bertujuan untuk mengolah urea menggunakan oksidasi konvensional (H2O2 dan Advanced Oxidation Processes (kombinasi H2O2-Fe2+ pada pH 5 dengan parameter yang digunakan adalah variasi konsen-trasi awal H2O2  dan konsentrasi Fe2+. Hasil percobaan menunjukkan bahwa penurunan konsentrasi urea tertinggi diperoleh pada penggunaan reagen fenton (8000 ppm H2O2 dan 500 ppm Fe2+, yaitu dapat menurunkan urea dari konsentrasi awal urea 2566,145 ppm menjadi 0 ppm. Kinetika reaksi dekomposisi urea menjadi amonium dan amonium menjadi nitrit dan nitrat yang diuji mengikuti laju kinetika reaksi orde 1 (satu terhadap urea dan orde satu terhadap amonium dengan konstanta laju reaksi masing-masing k1 = 0,019 dan k2 = 0,022 min-1.

  6. One-step preparation of nanostructured martite catalyst and graphite electrode by glow discharge plasma for heterogeneous electro-Fenton like process.

    Science.gov (United States)

    Khataee, Alireza; Sajjadi, Saeed; Hasanzadeh, Aliyeh; Vahid, Behrouz; Joo, Sang Woo

    2017-09-01

    Natural Martite ore particles and graphite were modified by alternating current (AC) glow discharge plasma to form nanostructured catalyst and cathode electrode for using in the heterogeneous-electro Fenton-like (Het-EF-like) process. The performance of the plasma-treated martite (PTM) and graphite electrode (PTGE) was studied for the treatment of paraquat herbicide in a batch system. 85.78% degradation efficiency for 20 mg L -1 paraquat was achieved in the modified process under desired operational conditions (i.e. current intensity of 300 mA, catalyst amount of 1 g L -1 , pH = 6, and background electrolyte (Na 2 SO 4 ) concentration of 0.05 mol L -1 ) which was higher than the 41.03% for the unmodified one after 150 min of treatment. The ecofriendly modification of the martite particles and the graphite electrode, no chemical needed, low leached iron and milder operational pH were the main privileges of plasma utilization. Moreover, the degradation efficiency through the process was not declined after five repeated cycles at the optimized conditions, which proved the stability of the nanostructured PTM and PTGE in the long-term usage. The archived results exhibit this method is the first example of high efficient, cost-effective, and environment-friendly method for generation of nanostructured samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Fenton detemplation of ordered (meso)porous materials

    NARCIS (Netherlands)

    Melian-Cabrera, I.; Osman, A. H.; van Eck, E. R. H.; Kentgens, Arno P.M.; Polushkin, E.; Kapteijn, F.; Moulijn, J. A.; Xu, R; Gao, Z; Chen, J; Yan, W

    2007-01-01

    This article describes a new methodology (Fenton detemplation), which consists of removing the template by chemical oxidation and develop the material's porosity. The oxidizing agents are OH radicals, which are generated from H(2)O(2) in the presence of catalytic amounts of Fe cations. This is known

  8. Degradation and ecotoxicity of dye Reactive Black 5 after reductive-oxidative process : Environmental Science and Pollution Research.

    Science.gov (United States)

    Cuervo Lumbaque, Elisabeth; Gomes, Monike Felipe; Da Silva Carvalho, Vanessa; de Freitas, Adriane Martins; Tiburtius, Elaine Regina Lopes

    2017-03-01

    This research paper describes the study of a reduction-oxidation system using commercial steel wool (Fe 0 ) and H 2 O 2 for degradation of the dye Reactive Black 5 and aromatic compounds in water. The reductive process alone allowed the almost complete removal of color (97 ± 1 %) after 60 min of reaction. The decrease in spectral area (λ = 599 nm) associated with the chromophore group indicates breakage of the azo bonds. Moreover, the significant change in UV spectra can be associated with the formation of aromatic amines. Regarding the transformation products, a spectrophotometric method based on the diazotization reaction was employed to identify aromatic amines after reductive process, using sulfanilic acid as a model of aromatic amines. In addition, association with Fenton reagents improved the efficiency in the system with 93 ± 1 % degradation of intermediates formed during the reductive process. Ecotoxicological analysis revealed that the dye solution, after the reductive and oxidative processes, was not toxic to Lactuca sativa seeds. For Daphnia magna, the EC 50 (%) values observed revealed that dye solution has an EC 50 (%) = 74.1 and after reductive process, the toxicity increased (EC 50 (%) = 63.5), which might be related to the formation of aromatic amines. However, after the Fenton process, the EC 50 (%) was >100. These results demonstrated that the Fenton reaction using steel wool as an iron source was very efficient to decrease color, aromatic transformation products, and the ecotoxicity of Reactive Black 5 in solution.

  9. Degradation of direct yellow 9 by electro-Fenton: process study and optimization and, monitoring of treated water toxicity using catalase.

    Science.gov (United States)

    Kourdali, Sidali; Badis, Abdelmalek; Boucherit, Ahmed

    2014-12-01

    The present study was undertaken to investigate the degradation and removal of direct yellow 9 (DY9) by the electro-Fenton (EF) process in batch reactor using iron and stainless steel electrodes. DY9 removal decreased with the increase in pH (3 to 8) and increased with the increase in current intensity (0.05 to 0.2A) and [H2O2] (0 to 0.5gL(-1), but not with high doses which led to low rates of DY9 removal and OH(∙) uptake). The regression quadratic models describing DY9 degradation yield "R (percent)" and electrical energy consumption "EEC (kWhkg(-1))" were validated by the analysis of variance (ANOVA) and were both noted to fit well with the experimental data. The R(2) correlation coefficients (0.995, 0.978), those adjusted coefficients (0.986, 0.939), and F values (110.7, 24.9) obtained for the responses validated the efficiency of model. The results revealed that among several other parameters, EEC depended essentially on the degradation yield. The eco-toxicity tests showed a positive correlation between catalase activity and DY9 concentration, and catalase could be qualitatively identified to assess the effect of dye and its by-products generated during the EF process. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Microgravity Processing of Oxide Superconductors

    Science.gov (United States)

    Olive, James R.; Hofmeister, William H.; Bayuzick, Robert J.; Vlasse, Marcus

    1999-01-01

    Considerable effort has been concentrated on the synthesis and characterization of high T(sub c) oxide superconducting materials. The YBaCuO system has received the most intense study, as this material has shown promise for the application of both thin film and bulk materials. There are many problems with the application of bulk materials- weak links, poor connectivity, small coherence length, oxygen content and control, environmental reactivity, phase stability, incongruent melting behavior, grain boundary contamination, brittle mechanical behavior, and flux creep. The extent to which these problems are intrinsic or associated with processing is the subject of controversy. This study seeks to understand solidification processing of these materials, and to use this knowledge for alternative processing strategies, which, at the very least, will improve the understanding of bulk material properties and deficiencies. In general, the phase diagram studies of the YBaCuO system have concentrated on solid state reactions and on the Y2BaCuO(x) + liquid yields YBa2Cu3O(7-delta) peritectic reaction. Little information is available on the complete melting relations, undercooling, and solidification behavior of these materials. In addition, rare earth substitutions such as Nd and Gd affect the liquidus and phase relations. These materials have promising applications, but lack of information on the high temperature phase relations has hampered research. In general, the understanding of undercooling and solidification of high temperature oxide systems lags behind the science of these phenomena in metallic systems. Therefore, this research investigates the fundamental melting relations, undercooling, and solidification behavior of oxide superconductors with an emphasis on improving ground based synthesis of these materials.

  11. Simultaneous E. coli inactivation and NOM degradation in river water via photo-Fenton process at natural pH in solar CPC reactor. A new way for enhancing solar disinfection of natural water.

    Science.gov (United States)

    Moncayo-Lasso, Alejandro; Sanabria, Janeth; Pulgarin, César; Benítez, Norberto

    2009-09-01

    Bacteria inactivation and natural organic matter oxidation in river water was simultaneously conducted via photo-Fenton reaction at "natural" pH ( approximately 6.5) containing 0.6 mg L(-1) of Fe(3+) and 10 mg L(-1) of H(2)O(2). The experiments were carried out by using a solar compound parabolic collector on river water previously filtered by a slow sand filtration system and voluntarily spiked with Escherichia coli. Fifty five percent of 5.3 mg L(-1) of dissolved organic carbon was mineralized whereas total disinfection was observed without re-growth after 24h in the dark.

  12. Microgravity Processing of Oxide Superconductors

    Science.gov (United States)

    Hofmeister, William H.; Bayuzick, Robert J.; Vlasse, Marcus; McCallum, William; Peters, Palmer (Technical Monitor)

    2000-01-01

    The primary goal is to understand the microstructures which develop under the nonequilibrium solidification conditions achieved by melt processing in copper oxide superconductor systems. More specifically, to define the liquidus at the Y- 1:2:3 composition, the Nd-1:2:3 composition, and several intermediate partial substitution points between pure Y-1:2:3 and Nd-1:2:3. A secondary goal has been to understand resultant solidification morphologies and pathways under a variety of experimental conditions and to use this knowledge to better characterize solidification phenomena in these systems.

  13. Removal of binary dyes mixtures with opposite and similar charges by adsorption, coagulation/flocculation and catalytic oxidation in the presence of CeO2/H2O2 Fenton-like system.

    Science.gov (United States)

    Issa Hamoud, Houeida; Finqueneisel, Gisèle; Azambre, Bruno

    2017-06-15

    In this study, the removal of binary mixtures of dyes with similar (Orange II/Acid Green 25) or opposite charges (Orange II/Malachite Green) was investigated either by simple adsorption on ceria or by the heterogeneous Fenton reaction in presence of H 2 O 2 . First, the CeO 2 nanocatalyst with high specific surface area (269 m 2 /g) and small crystal size (5 nm) was characterized using XRD, Raman spectroscopy and N 2 physisorption at 77 K. The adsorption of single dyes was studied either from thermodynamic and kinetic viewpoints. It is shown that the adsorption of dyes on ceria surface is highly pH-dependent and followed a pseudo-second order kinetic model. Adsorption isotherms fit well the Langmuir model with a complete monolayer coverage and higher affinity towards Orange II at pH 3, compared to other dyes. For the (Orange II/Acid Green 25) mixture, both the amounts of dyes adsorbed on ceria surface and discoloration rates measured from Fenton experiments were decreased by comparison with single dyes. This is due to the adsorption competition existing onto the same surface Ce x+ sites and the reaction competition with hydroxyl radicals, respectively. The behavior of the (Orange II/Malachite Green) mixture is markedly different. Dyes with opposite charges undergo paired adsorption on ceria as well as homogeneous and heterogeneous coagulation/flocculation processes, but can also be removed by heterogeneous Fenton process. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Application of Fenton's reagent as a pretreatment step in biological degradation of polyaromatic hydrocarbons

    International Nuclear Information System (INIS)

    Kelley, R.L.; Gauger, W.K.; Srivastava, V.J.

    1991-01-01

    Fenton's reagent (H 2 O 2 and Fe ++ ) has been used for chemical oxidation of numerous organic compounds in water treatment schemes. In this study, the Institute of Gas Technology (IGT) applied Fenton's treatment to polynuclear aromatic hydrocarbons (PAHs) and PAH-contaminated soils. Fenton's treatment was very reactive with PAHs, causing rapid modification of the parental compounds to oxidized products and complete degradation to CO 2 . This treatment was more effective on chemically reactive PAHs, such as benzo(a)pyrene and phenanthrene. Important parameters and conditions for Fenton's treatment of PAHs in solution and soil matrices have been identified. As much as 99% of the PAHs on soil matrices can be removed by treatment with Fenton's reagent

  15. Mechanism and Parameter Optimization of Fenton's Reagent Integrated with Surfactant Pretreatment to Improve Sludge Dewaterability.

    Directory of Open Access Journals (Sweden)

    Yi Xing

    Full Text Available Sludge dewatering can effectively reduce the volume and mass of sludge for subsequent treatment and disposal. The work validated the potential of Fenton's reagent combined with dodecyl dimethyl benzyl ammonium chloride (DDBAC in improving sludge dewaterability and proposed the mechanism of joint conditioning. The composite conditioner dosage was optimized using response surface methodology. Results indicated the good conditioning capability of the composite conditioners. The optimum dosages for H2O2, Fe2+, and DDBAC were 44.6, 39.6, and 71.0 mg/g, respectively, at which a sludge cake water content of 59.67% could be achieved. Moreover, a second-order polynomial equation was developed to describe the behavior of joint conditioning. Analysis of the reaction mechanism showed that Fenton oxidation effectively decomposed extracellular polymeric substance (EPS, including loosely bound EPS (LB-EPS and tightly bound EPS (TB-EPS, into dissolved organics, such as proteins and polysaccharides. The process facilitated the conversion of the bound water into free water. Furthermore, DDBAC further released the bound water through solubilization of TB-EPS and LB-EPS after the Fenton reaction. The bound water content of the sludge conditioned with Fenton's reagent decreased from 3.15 to 1.36 g/g and further decreased to 1.08 g/g with the addition of DDBAC. High-performance liquid chromatography analysis verified that the composite conditioning could oxidize and hydrolyze EPS into low-molecular-mass organics (e.g., formic and acetic acid, thereby facilitating the release of bound water.

  16. Investigations on the Synthesis and Properties of Fe2O3/Bi2O2CO3 in the Photocatalytic and Fenton-like Process

    Science.gov (United States)

    Sun, Dongxue; Shen, Tingting; Sun, Jing; Wang, Chen; Wang, Xikui

    2018-01-01

    Catalyst of Bi2O2CO3 and Fe2O3 modified Bi2O2CO3 (Fe2O3/Bi2O2CO3) were prepared by hydrothermal method and characterized by X-ray diffractions (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM) and UV-vis DRS. The catalytic activity of Bi2O2CO3 and Fe2O3/Bi2O2CO3 were comparatively investigated in the photodegradation and Fento-like process. Rhodamine B(RhB) was selected as the target pollutant under the irradiation of 300 W xenon lamp. The results indicated that Fe2O3 plays a great role in the enhancing the treatment efficiency and the and the maximum reaction rate was achieved at the Fe2O3 loading of 1.5%. The Fenton-like degradation rate constant of RhB with bare Bi2O2CO3 in dark is 0.4 min-1, while that with 1.5 Fe2O3/Bi2O2CO3 increases to 28.4 min-1 under visible light irradiation, a 71-fold improvement. It is expected to shed a new light for the constructing novel composite photocatalyst and also provide a potential method for the removal of dyes in the aqueous system.

  17. Improved removal performance and mechanism investigation of papermaking wastewater treatment using manganese enhanced Fenton reaction.

    Science.gov (United States)

    Wang, Yingcai; Wang, Can; Shi, Shuai; Fang, Shuai

    2018-06-01

    The effects of Mn(II) on Fenton system to treat papermaking wastewater and the mechanism of Mn(II) enhanced Fenton reaction were investigated in this study. The chemical oxygen demand (COD) removal efficiency was enhanced in the presence of Mn(II), which increased by 19% compared with that of the Fenton system alone. The pseudo-first order reaction kinetic rate constant of Mn(II)/Fenton system was 2.11 times higher than that of Fenton system. 67%-81% COD were removed with the increasing Mn(II) concentration from 0 to 0.8 g/L. COD removal efficiency was also enhanced in a wider pH range (3-7), which indicated the operation parameters of Fenton technology could be broadened to a milder condition. The study of the mechanism showed that Mn(II) participated in the oxidation and coagulation stages in Fenton system. In the oxidation stage, Mn(II) promotes the production of HO 2 •/ O 2 • - , then HO 2 •/ O 2 • - reacts with Fe(III) to accelerate the formation of Fe(II), and finally accelerates the production of HO•. Meantime MnMnO 3 and Fe(OH) 3 forms in the coagulation stage, facilitating the removal of suspended substances and a large amount of COD, which enhances the overall COD removal of papermaking wastewater. This study provided a detailed mechanism to improve practical applications of Fenton technology.

  18. A study on removal of elemental mercury in flue gas using fenton solution

    International Nuclear Information System (INIS)

    Liu, Yangxian; Wang, Yan; Wang, Qian; Pan, Jianfeng; Zhang, Yongchun; Zhou, Jianfei; Zhang, Jun

    2015-01-01

    Highlights: • A novel technique on oxidation of Hg 0 using Fenton was proposed. • The effects of several process parameters on Hg 0 removal were studied. • Products and ·OH in solution were detected. • Reaction mechanism of Hg 0 removal was studied. • Simultaneous removal of Hg 0 , NO and SO 2 was also studied. - Abstract: A novel technique on oxidation-separation of elemental mercury (Hg 0 ) in flue gas using Fenton solution in a bubbling reactor was proposed. The effects of several process parameters (H 2 O 2 concentration, Hg 0 inlet concentration, Fe 2+ concentration, solution temperature, solution pH, gas flow) and several flue gas components (NO, SO 2 , O 2 , CO 2 , inorganic ions and particulate matters on Hg 0 removal were studied. The results indicate that H 2 O 2 concentration, Fe 2+ concentration, solution pH and gas flow have great effects on Hg 0 removal. Solution temperature, Hg 0 , NO, SO 2 , CO 3 2− and HCO 3 − concentrations also have significant effects on Hg 0 removal. However, Cl − , SO 4 2− , NO 3 − , O 2 and CO 2 concentrations only have slight effects on Hg 0 removal. Furthermore, reaction mechanism of Hg 0 removal and simultaneous removal process of Hg 0 , NO and SO 2 were also studied. Hg 0 is removed by oxidation of ·OH and oxidation of H 2 O 2 . The simultaneous removal efficiencies of 100% for SO 2 , 100% for Hg 0 and 88.3% for NO were obtained under optimal test conditions. The results demonstrated the feasibility of Hg 0 removal and simultaneous removal of Hg 0 , SO 2 and NO using Fenton solution in a bubbling reactor

  19. Removal of Mefenamic acid from aqueous solutions by oxidative process: Optimization through experimental design and HPLC/UV analysis.

    Science.gov (United States)

    Colombo, Renata; Ferreira, Tanare C R; Ferreira, Renato A; Lanza, Marcos R V

    2016-02-01

    Mefenamic acid (MEF) is a non-steroidal anti-inflammatory drug indicated for relief of mild to moderate pain, and for the treatment of primary dysmenorrhea. The presence of MEF in raw and sewage waters has been detected worldwide at concentrations exceeding the predicted no-effect concentration. In this study, using experimental designs, different oxidative processes (H2O2, H2O2/UV, fenton and Photo-fenton) were simultaneously evaluated for MEF degradation efficiency. The influence and interaction effects of the most important variables in the oxidative process (concentration and addition mode of hydrogen peroxide, concentration and type of catalyst, pH, reaction period and presence/absence of light) were investigated. The parameters were determined based on the maximum efficiency to save time and minimize the consumption of reagents. According to the results, the photo-Fenton process is the best procedure to remove the drug from water. A reaction mixture containing 1.005 mmol L(-1) of ferrioxalate and 17.5 mmol L(-1) of hydrogen peroxide, added at the initial reaction period, pH of 6.1 and 60 min of degradation indicated the most efficient degradation, promoting 95% of MEF removal. The development and validation of a rapid and efficient qualitative and quantitative HPLC/UV methodology for detecting this pollutant in aqueous solution is also reported. The method can be applied in water quality control that is generated and/or treated in municipal or industrial wastewater treatment plants. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Remediation of polluted soils contaminated with Linear Alkyl Benzenes using Fenton's reagent

    Directory of Open Access Journals (Sweden)

    Douglas do Nascimento Silva

    2005-06-01

    Full Text Available Linear Alkyl Benzenes (LABs are used as insulating oil for electric cables. When it happens a spill, LABs they are basically sorbed in the soil, because, these compounds have high hidrophobicity and low vapor pressure. The conventional methods of treatment of soils are not efficient. The Fenton's reaction (reaction between a solution of iron II and hydrogen peroxide it generates hydroxyl radicals, not selective, and capable of oxidize a great variety of organic compounds. A study was conducted to evaluate the viability of use of the Fenton's reagents to promote the remediation of polluted soils with Linear Alkyl Benzenes. A column was especially projected for these experiments, packed with a sandy and other soil loamy. The pH of the soil was not altered. The obtained results demonstrated the technical viability of the process of injection of the Fenton's reagents for the treatment of polluted areas with LABs.Os Linear Alquilbenzenos (LABs são usados como fluido refrigerante de cabos elétricos. Quando ocorre um vazamento, os LABs ficam basicamente adsorvidos no solo, pois, são compostos bastante hidrofóbicos e com baixa pressão de vapor. Os métodos convencionais de tratamento de solos não são eficientes. A reação de Fenton (solução de ferro II e peróxido de hidrogênio gera radicais hidroxila, não seletivos, e capazes de oxidar uma grande variedade de compostos orgânicos, chegando a mineralização dos mesmos. Neste trabalho foi estudada a viabilidade de utilização dos reagentes de Fenton para promover a remediação de solos contaminados com LABs. Utilizou-se uma coluna especialmente projetada para estes experimentos, empacotada com um solo arenoso e outro argiloso. O pH do solo não foi alterado. Os resultados obtidos demonstram a viabilidade técnica do processo de injeção dos reagentes de Fenton para o tratamento de áreas contaminadas com LABs.