WorldWideScience

Sample records for heavy metals removal

  1. MICROBIAL REMOVAL OF HEAVY METALS FROM WASTEWATER

    Justyna Koc-Jurczyk

    2014-10-01

    Full Text Available Industrialization and urbanization result in increase of heavy metals released into the environment (soil, lakes, rivers, seas, oceans, groundwater. Studies on biosorption of heavy metals are aimed to specify types of microorganisms which could efficiently bind metals. This approach has a very important significance for both slowing down metals exploitation by recovery, and also reduction of environmental pollution by decrease of their excessive concentration. Recent studies have reported about the capabilities of fungi, algae, yeasts, bacteria, waste and agricultural residues or materials containing chitosan derived from crustacean shells as a biosorbents. Biohydrometallurgy could be considered as a new “green” technology of heavy metals removal from wastewater.

  2. Removal of heavy metals using waste eggshell

    2007-01-01

    The removal capacity of toxic heavy metals by the reused eggshell was studied. As a pretreatment process for the preparation of reused material from waste eggshell, calcination was performed in the furnace at 800℃ for 2 h after crushing the dried waste eggshell. Calcination behavior, qualitative and quantitative elemental information, mineral type and surface characteristics before and after calcination of eggshell were examined by thermal gravimetric analysis (TGA), X-ray fluorescence (XRF), X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. After calcination, the major inorganic composition was identified as Ca (lime, 99.63%) and K, P and Sr were identified as minor components. When calcined eggshell was applied in the treatment of synthetic wastewater containing heavy metals, a complete removal of Cd as well as above 99% removal of Cr was observed after 10 min. Although the natural eggshell had some removal capacity of Cd and Cr, a complete removal was not accomplished even after 60 min due to quite slower removal rate. However, in contrast to Cd and Cr, an efficient removal of Pb was observed with the natural eggshell rather than the calcined eggshell. From the application of the calcined eggshell in the treatment of real electroplating wastewater, the calcined eggshell showed a promising removal capacity of heavy metal ions as well as had a good neutralization capacity in the treatment of strong acidic wastewater.

  3. Heavy metal removal and recovery using microorganisms

    Microorganisms -- bacteria, fungi, and microalgae -- can accumulate relatively large amounts of toxic heavy metals and radionuclides from the environment. These organisms often exhibit specificity for particular metals. The metal content of microbial biomass can be a substantial fraction of total dry weight with concentration factors (metal in dry biomass to metal in solution) exceeding one million in some cases. Both living and inert (dead) microbial biomass can be used to reduce heavy metal concentrations in contaminated waters to very low levels -- parts per billion and even lower. In many respects (e.g. specificity, residual metal concentrations, accumulation factors, and economics) microbial bioremoval processes can be superior to conventional processes, such as ion exchange and caustic (lime or hydroxide) precipitation for heavy metals removal from waste and contaminated waters. Thus, bioremoval could be developed to contribute to the clean-up of wastes at the Savannah River Site (SRS) and other DOE facilities. However, the potential advantages of bioremoval processes must still be developed into practical operating systems. A detailed review of the literature suggests that appropriate bioremoval processes could be developed for the SRS. There is great variability from one biomass source to another in bioremoval capabilities. Bioremoval is affected by pH, other ions, temperature, and many other factors. The biological (living vs. dead) and physical (immobilized vs. dispersed) characteristics of the biomass also greatly affect metal binding. Even subtle differences in the microbial biomass, such as the conditions under which it was cultivated, can have major effects on heavy metal binding

  4. Removal of heavy metals from biowaste: modelling of heavy metal behaviour and development of removal technologies.

    Veeken, A.

    1998-01-01

    In the Netherlands, recycling of solid organic waste streams as compost only becomes possible if the compost complies with the heavy metals standards of the BOOM decree. This dissertation focuses on the removal of heavy metals from biowaste, i.e. the source separated organic fraction of municipal so

  5. Removal of heavy metals from biowaste: modelling of heavy metal behaviour and development of removal technologies.

    Veeken, A.

    1998-01-01

    In the Netherlands, recycling of solid organic waste streams as compost only becomes possible if the compost complies with the heavy metals standards of the BOOM decree. This dissertation focuses on the removal of heavy metals from biowaste, i.e. the source separated organic fraction of municipal solid waste. Biowaste is referred to as an organic waste stream but surprisingly it was found that a large part of biowaste is composed of inorganic material, i.e. sand, silt and clay minerals. The i...

  6. MICROBIAL REMOVAL OF HEAVY METALS FROM WASTEWATER

    Justyna Koc-Jurczyk

    2014-01-01

    Industrialization and urbanization result in increase of heavy metals released into the environment (soil, lakes, rivers, seas, oceans, groundwater). Studies on biosorption of heavy metals are aimed to specify types of microorganisms which could efficiently bind metals. This approach has a very important significance for both slowing down metals exploitation by recovery, and also reduction of environmental pollution by decrease of their excessive concentration. Recent studies have reported ab...

  7. Removal of heavy metal ions from aqueous solutions using clinoptilolite

    Golomeova, Mirjana; Zendelska, Afrodita; Krstev, Boris; Golomeov, Blagoj; Krstev, Aleksandar

    2015-01-01

    Heavy metals are a common pollutant found in various industrial effluents. They are often encountered in mining operations and acid mine drainage. The heavy metals are highly toxic and are non-biodegradable, therefore they must be removed from the polluted streams in order to meet increasingly stringent environmental quality standards. Removal of heavy metals can be accomplished by a variety of techniques. Conventional methods typically involve the use of processes such as coag...

  8. Removal of Heavy Metals in Effluent by Adsorption and Coagulation

    Feng Ting LI; Xia LI; Bing Ru ZHANG; Qing Hua OUYANG

    2004-01-01

    The silicate colloids with an average diameter 100 nm, were prepared by the hydrolysis of tetraethoxysilane (TES), NH4OH (30%) and then modified by (3-mercaptopropyl) trimethoxysilane ( APS). The colloids can adsorb heavy metals such as Pb and Cr in effluent and after adsorption the colloids can be separated by coagulation of aluminum sulfate. The removal of heavy metals is up to 99%.

  9. Heavy metals removal from dredged sediments using electro kinetics

    Ammami M. T.

    2013-04-01

    Full Text Available This study focuses on the use of a remediation process to remove particle-bound recalcitrant pollutants (heavy metals from dredged harbor sediments which must be previously treated before reuse in civil engineering. Electrokinetic (EK remediation is generally accepted as one of the most suitable technologies for extracting cationic heavy metals from fine grained sediments. Many batch tests were performed to better understand the capacity of various additives to improve sediment decontamination (when applying a constant voltage gradient of 1 V.cm-1, and the combination of enhancing agents (acids + surfactants were assessed to obtain an efficient removal of heavy metals. We succeeded in proving that mixing citric acid and a nonionic surfactant (Tween 20, additives which are environmentally friendly, was a good association to enhance heavy metals (Cd, Cr, Cu, Pb and Zn removal.

  10. Removal of heavy metals from aqueous solutions using opalized tuff

    Golomeova, Mirjana; Zendelska, Afrodita; Golomeov, Blagoj; Krstev, Boris; Jakupi, Shaban

    2015-01-01

    This paper presents the results of the examination of the possibility of applying opalized tuff as a natural raw material for disposal of heavy metals (copper, zinc, manganese and lead) from aqueous solutions. Of actual experiments obtained results show that working conditions attaching to the removal of Cu and Pb ions is more than 91% of zinc ions is above 81%, while manganese ions are removed about 77% .On this can be concluded that the removal of examined heavy metals using opalized tuff i...

  11. Heavy metals removal from dredged sediments using electro kinetics

    Ammami M. T.; Benamar A.; Koltalo F.; Wang H. Q.; LeDerf F.

    2013-01-01

    This study focuses on the use of a remediation process to remove particle-bound recalcitrant pollutants (heavy metals) from dredged harbor sediments which must be previously treated before reuse in civil engineering. Electrokinetic (EK) remediation is generally accepted as one of the most suitable technologies for extracting cationic heavy metals from fine grained sediments. Many batch tests were performed to better understand the capacity of various additives to improve sediment decontaminat...

  12. Science Letters: Simultaneous removal of nitrate and heavy metals by iron metal

    HAO Zhi-wei; XU Xin-hua; JIN Jian; HE Ping; LIU Yong; WANG Da-hui

    2005-01-01

    Great attention should be paid now to simultaneously removing common pollutants, especially inorganic pollutants such as nitrate and heavy metals, as individual removal has been investigated extensively. Removing common pollutants simultaneously by iron metal is a very effective alternative method. Near neutral pH, heavy metals, such as copper and nickel, can be removed rapidly by iron metal, while nitrate removal very much slower than that of copper and nickel, and copper can accelerate nitrate removal when both are removed simultaneously. Even a little amount of copper can enhance nitrate removal efficiently.Different mechanisms of these contaminants removal by iron metal were also discussed.

  13. New trends in removing heavy metals from wastewater.

    Zhao, Meihua; Xu, Ying; Zhang, Chaosheng; Rong, Hongwei; Zeng, Guangming

    2016-08-01

    With the development of researches, the treatments of wastewater have reached a certain level. Whereas, heavy metals in wastewater cause special concern in recent times due to their recalcitrance and persistence in the environment. Therefore, it is important to get rid of the heavy metals in wastewater. The previous studies have provided many alternative processes in removing heavy metals from wastewater. This paper reviews the recent developments and various methods for the removal of heavy metals from wastewater. It also evaluates the advantages and limitations in application of these techniques. A particular focus is given to innovative removal processes including adsorption on abiological adsorbents, biosorption, and photocatalysis. Because these processes have leaded the new trends and attracted more and more researches in removing heavy metals from wastewater due to their high efficency, pluripotency and availability in a copious amount. In general, the applicability, characteristic of wastewater, cost-effectiveness, and plant simplicity are the key factors in selecting the most suitable method for the contaminated wastewater. PMID:27318819

  14. Plasma polymer-functionalized silica particles for heavy metals removal.

    Akhavan, Behnam; Jarvis, Karyn; Majewski, Peter

    2015-02-25

    Highly negatively charged particles were fabricated via an innovative plasma-assisted approach for the removal of heavy metal ions. Thiophene plasma polymerization was used to deposit sulfur-rich films onto silica particles followed by the introduction of oxidized sulfur functionalities, such as sulfonate and sulfonic acid, via water-plasma treatments. Surface chemistry analyses were conducted by X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectroscopy. Electrokinetic measurements quantified the zeta potentials and isoelectric points (IEPs) of modified particles and indicated significant decreases of zeta potentials and IEPs upon plasma modification of particles. Plasma polymerized thiophene-coated particles treated with water plasma for 10 min exhibited an IEP of less than 3.5. The effectiveness of developed surfaces in the adsorption of heavy metal ions was demonstrated through copper (Cu) and zinc (Zn) removal experiments. The removal of metal ions was examined through changing initial pH of solution, removal time, and mass of particles. Increasing the water plasma treatment time to 20 min significantly increased the metal removal efficiency (MRE) of modified particles, whereas further increasing the plasma treatment time reduced the MRE due to the influence of an ablation mechanism. The developed particulate surfaces were capable of removing more than 96.7% of both Cu and Zn ions in 1 h. The combination of plasma polymerization and oxidative plasma treatment is an effective method for the fabrication of new adsorbents for the removal of heavy metals. PMID:25603034

  15. Removal of heavy metal from industrial effluents using Baker's yeast

    Ferdous, Anika; Maisha, Nuzhat; Sultana, Nayer; Ahmed, Shoeb

    2016-07-01

    Bioremediation of wastewater containing heavy metals is one of the major challenges in environmental biotechnology. Heavy metals are not degraded and as a result they remain in the ecosystem, and pose serious health hazards as it comes in contact with human due to anthropogenic activities. Biological treatment with various microorganisms has been practiced widely in recent past, however, accessing and maintaining the microorganisms have always been a challenge. Microorganisms like Baker's yeast can be very promising biosorbents as they offer high surface to volume ratio, large availability, rapid kinetics of adsorption and desorption and low cost. The main aim of this study is to evaluate the applicability of the biosorption process using baker's yeast. Here we present an experimental investigation of biosorption of Chromium (Cr) from water using commercial Baker's Yeast. It was envisaged that yeast, dead or alive, would adsorb heavy metals, however, operating parameters could play vital roles in determining the removal efficiency. Parameters, such as incubation time, pH, amount of biosorbent and heavy metal concentration were varied to investigate the impacts of those parameters on removal efficiency. Rate of removal was found to be inversely proportional to the initial Cr (+6) concentrations but the removal rate per unit biomass was a weakly dependent on initial Cr(+6) concentrations. Biosorption process was found to be more efficient at lower pH and it exhibited lower removal with the increase in solution pH. The optimum incubation time was found to be between 6-8 hours and optimum pH for the metal ion solution was 2. The effluents produced in leather industries are the major source of chromium pollution in Bangladesh and this study has presented a very cost effective yet efficient heavy metal removal approach that can be adopted for such kind of wastewater.

  16. Simultaneous heavy metal removal mechanism by dead macrophytes.

    Miretzky, Patricia; Saralegui, Andrea; Fernández Cirelli, Alicia

    2006-01-01

    The use of dead, dried aquatic plants, for water removal of metals derived from industrial activities as a simple biosorbent material has been increasing in the last years. The mechanism of simultaneous metal removal (Cd2+, Ni2+, Cu2+, Zn2+ and Pb2+) by 3 macrophytes biomass (Spirodela intermedia, Lemna minor and Pistia stratiotes) was investigated. L. minor biomass presented the highest mean removal percentage and P. stratiotes the lowest for all metals tested. Pb2+ and Cd2+ were more efficiently removed by the three of them. The simultaneous metal sorption data were analysed according to Langmuir and Freundlich isotherms. Data fitted the Langmuir model only for Ni and Cd, but Freundlich isotherm for all metals tested, as it was expected. The K(F) values showed that Pb was the metal more efficiently removed from water solution. The adsorption process for the three species studied followed first order kinetics. The mechanism involved in biosorption resulted ion exchange between monovalent metals as counter ions present in the macrophytes biomass and heavy metal ions and protons taken up from water. No significant differences were observed in the metal exchange amounts while using multi-metal or individual metal solutions. PMID:15990152

  17. Electrodialytic removal of heavy metals from fly ashes

    Pedersen, Anne Juul

    2002-01-01

    The aim of the Ph.D. work was to develop the electrodialytic remediation method for removal of heavy metals from fly ashes. The work was focused on two types of fly ashes: fly ashes from wood combustion and fly ashes from municipal solid waste incineration....

  18. Removal and recovery of heavy metals of residual water industrial

    On the next work the state of the art about the different methods and technologies for the present removal and recovery of heavy metals for the de-contamination and control of industrial wastewater is presented. Further more, it is introduce a removal alternative for chromium (III) and chromium (V I) using a solid waste material as an adsorbent, obtaining successful results which makes this proposal circumscribe into the clean technology program and residues bag

  19. Individual and competitive removal of heavy metals using capacitive deionization.

    Huang, Zhe; Lu, Lu; Cai, Zhenxiao; Ren, Zhiyong Jason

    2016-01-25

    This study presents the viability and preference of capacitive deionization (CDI) for removing different heavy metal ions in various conditions. The removal performance and mechanisms of three ions, cadmium (Cd(2+)), lead (Pb(2+)) and chromium (Cr(3+)) were investigated individually and as a mixture under different applied voltages and ion concentrations. It was found that CDI could effectively remove these metals, and the performance was positively correlated with the applied voltage. When 1.2 V was applied into solution containing 0.5mM individual ions, the Cd(2+), Pb(2+), and Cr(3+) removal was 32%, 43%, and 52%, respectively, and the electrosorption played a bigger role in Cd(2+) removal than for the other two ions. Interestingly, while the removal of Pb(2+) and Cr(3+) remained at a similar level of 46% in the mixture of three ions, the Cd(2+) removal significantly decreased to 14%. Similar patterns were observed when 0.05 mM was used to simulate natural contaminated water condition, but the removal efficiencies were much higher, with the removal of Pb(2+), Cr(3+), and Cd(2+) increased to 81%, 78%, and 42%, respectively. The low valence charge and lack of physical sorption of Cd(2+) were believed to be the reason for the removal behavior, and advanced microscopic analysis showed clear deposits of metal ions on the cathode surface after operation. PMID:26476320

  20. Novel forward osmosis process to effectively remove heavy metal ions

    Cui, Yue

    2014-10-01

    In this study, a novel forward osmosis (FO) process for the removal of heavy metal ions from wastewater was demonstrated for the first time. The proposed FO process consists of a thin-film composite (TFC) FO membrane made from interfacial polymerization on a macrovoid-free polyimide support and a novel bulky hydroacid complex Na4[Co(C6H4O7)2]·r2H2O (Na-Co-CA) as the draw solute to minimize the reverse solute flux. The removal of six heavy metal solutions, i.e., Na2Cr2O7, Na2HAsO4, Pb(NO3)2, CdCl2, CuSO4, Hg(NO3)2, were successfully demonstrated. Water fluxes around 11L/m2/h (LMH) were harvested with heavy metals rejections of more than 99.5% when employing 1M Na-Co-CA as the draw solution to process 2000ppm(1 ppm=1 mg/L) heavy metal solutions at room temperature. This FO performance outperforms most nanofiltration (NF) processes. In addition, the high rejections were maintained at 99.5% when a more concentrated draw solution (1.5M) or feed solution (5000ppm) was utilized. Furthermore, rejections greater than 99.7% were still achieved with an enhanced water flux of 16.5LMH by operating the FO process at 60°C. The impressive heavy metal rejections and satisfactory water flux under various conditions suggest great potential of the newly developed FO system for the treatment of heavy metal wastewater. © 2014 Elsevier B.V.

  1. Physiochemicals and Heavy Metal Removal from Domestic Wastewater via Phycoremediation

    Ab Razak Abdul Rafiq

    2016-01-01

    Full Text Available The common sources of water pollution in Malaysia are domestic sewage and industrial waste. Therefore, domestic wastewater quality effluent should be improved before discharged through the outlets. The alternative method of treatment uses microalgae for water remediation which is known as phycoremediation was applied. This technique is to remove or reduce nutrients and harmful pollutants in domestic wastewater. Thus, objective of the present study is to bioremediate the physiochemical and heavy metal from domestic wastewater using freshwater green microalgae Botryococcus sp. A photobioreactor is used to treat the wastewater by employing the microalgae Botryococcus sp. as a vital part of the treatment system. The results show that several nutrients have been reduced successfully such as phosphate and total phosphorus of 100% removal, inorganic carbon of 99% removal, total carbon of 42% removal, and nitrate of 10%. The most prominent heavy metal content that has been removed is Aluminium of 41%. At the same time, the growth of microalgae Botryococcus sp. in this wastewater has achieved the maximum value at Day 4 with 2.58 × 105 cell/ml only. These results show the potential of Botryococcus sp. cultivation as an alternative method to treat domestic wastewater and any other biotechnology works in the future.

  2. Electrodialytic Removal of Heavy Metals from Different Solid Waste Products

    Ottosen, Lisbeth M.; Christensen, Iben Vernegren; Pedersen, Anne Juul;

    2003-01-01

    the method could be used for removal of different heavy metals from impregnated wood waste, fly ash from straw combustion, and fly ash from municipal solid waste incineration. The best result was obtained with the wood waste where more than 80% of each of the polluting elements Cu, Cr and As was...... removed in a 7-day experiment in which oxalic acid was used as enhancement solution. From the straw ash, 66% of the Cd was removed, but 64% of the fly ash dry mass dissolved during the treatment. In this actual experiment, no enhancement solution was used but that will be necessary to avoid dissolution of...... the ash to such a high extent. For the fly ash from waste incineration, ammonium citrate was tested as enhancement solution and in 14 days 62% Cd, 53% Cu, 6% Pb, and 31% Zn were removed. The preliminary results were thus promising for developing the electrodialytic method to other products than soil...

  3. Triboelectrification-Enabled Self-Powered Detection and Removal of Heavy Metal Ions in Wastewater.

    Li, Zhaoling; Chen, Jun; Guo, Hengyu; Fan, Xing; Wen, Zhen; Yeh, Min-Hsin; Yu, Chongwen; Cao, Xia; Wang, Zhong Lin

    2016-04-01

    A fundamentally new working principle into the field of self-powered heavy-metal-ion detection and removal using the triboelectrification effect is introduced. The as-developed tribo-nanosensors can selectively detect common heavy metal ions. The water-driven triboelectric nanogenerator is taken as a sustainable power source for heavy-metal-ion removal by recycling the kinetic energy from flowing wastewater. PMID:26913810

  4. Application of Iron Oxide Nanomaterials for the Removal of Heavy Metals

    Pragnesh N. Dave; Lakhan V. Chopda

    2014-01-01

    In the 21st century water polluted by heavy metal is one of the environment problems. Various methods for removal of the heavy metal ions from the water have extensively been studied. Application of iron oxide nanaparticles based nanomaterials for removal of heavy metals is well-known adsorbents for remediation of water. Due to its important physiochemical property, inexpensive method and easy regeneration in the presence of external magnetic field make them more attractive toward water purif...

  5. Electrodialytic removal of heavy metals from different fly ashes. Influence of heavy metal speciation in the ashes

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Villumsen, Arne

    2003-01-01

    Electrodialytic Remediation has recently been suggested as a potential method for removal of heavy metals from fly ashes. In this work electrodialytic remediation of three different fly ashes, i.e. two municipal solid waste incinerator (MSWI) fly ashes and one wood combustion fly ash was studied in......-moval efficiencies were observed, especially for Pb and Zn. Cd, the sole heavy metal of environmental concern in the wood ash, was found more tightly bonded in this ash than in the two MSWI ashes. It was suggested that complex Cd-silicates are likely phases in the wood ash whereas more soluble, condensed phases are...... lab scale, and the results were discussed in relation to the expected heavy metal speciation in the ashes. In initial leaching experiments the pH-dependent desorption characteristics of the heavy metals Cd, Pb, Zn and Cu were analogous in the two MSWI ashes, and thus it was expected that the...

  6. Electrodialytic removal of heavy metals from different fly ashes. Influence of heavy metal speciation in the ashes

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Villumsen, Arne

    2003-01-01

    Electrodialytic Remediation has recently been suggested as a potential method for removal of heavy metals from fly ashes. In this work electrodialytic remediation of three different fly ashes, i.e. two municipal solid waste incinerator (MSWI) fly ashes and one wood combustion fly ash was studied in...... lab scale, and the results were discussed in relation to the expected heavy metal speciation in the ashes. In initial leaching experiments the pH-dependent desorption characteristics of the heavy metals Cd, Pb, Zn and Cu were analogous in the two MSWI ashes, and thus it was expected that the......-moval efficiencies were observed, especially for Pb and Zn. Cd, the sole heavy metal of environmental concern in the wood ash, was found more tightly bonded in this ash than in the two MSWI ashes. It was suggested that complex Cd-silicates are likely phases in the wood ash whereas more soluble, condensed phases are...

  7. To study the recovery of L-Cysteine using halloysite nanotubes after heavy metal removal

    Thakur, Juhi

    2016-04-01

    Industrial wastes are a major source of soil and water pollution that originate from mining industries, chemical industries, metal processing industries, etc. These wastes consist of a variety of chemicals including phenolics, heavy metals, etc. Use of industrial effluent and sewage sludge on agricultural land has become a common practice in the world which results in these toxic metals being transferred and ultimately concentrate in plant tissues from water and the soil. The metals that get accumulated, prove detrimental to plants themselves and may also cause damage to the healths of animals as well as man. This is because the heavy metals become toxins above certain concentrations, over a narrow range. As a further matter, these metals negatively affect the natural microbial populations as well, that leads to the disruption of fundamental ecological processes. However, many techniques and methods have been advanced to clear the heavy metal polluted soils and waters. One important method is by removing heavy metals with the help of amino acids like L-Cysteine and L-Penicillamine. But also, economy of removal of pollutant heavy metals from soils and waters is a major concern. Present study helps in decreasing the cost for large-scale removal of heavy metals from polluted water by recovering the amino acid (L-Cysteine) after removal of nickel (Ni+2) at a fixed pH, by binding the Ni+2 with halloysite nanotubes(HNT), so that L-Cysteine can be reused again for removal of heavy metals.

  8. Mechanisms of heavy metal removal using microorganisms as biosorbent.

    Javanbakht, Vahid; Alavi, Seyed Amir; Zilouei, Hamid

    2014-01-01

    Release and distribution of heavy metals through industrial wastewaters has adverse affects on the environment via contamination of surface- and ground-water resources. Biosorption of heavy metals from aqueous solutions has been proved to be very promising, offering significant advantages such as low cost, availability, profitability, ease of operation, and high efficiency, especially when dealing with low concentrations. Residual biomasses of industrial microorganisms including bacteria, algae, fungi, and yeast have been found to be capable of efficiently accumulating heavy metals as biosorbent. This paper presents and investigates major mechanisms of biosorption and most of the functional groups involved. The biosorption process includes the following mechanisms: transport across cell membrane, complexation, ion exchange, precipitation, and physical adsorption. In order to understand how metals bind to the biomass, it is essential to identify the functional groups responsible for metal binding. Most of these groups have been characterized on the cell walls. The biosorbent contains a variety of functional sites including carboxyl, imidazole, sulfydryl, amino, phosphate, sulfate, thioether, phenol, carbonyl, amide, and hydroxyl moieties that are responsible for metal adsorption. These could be helpful to improve biosorbents through modification of surface reactive sites via surface grafting and/or exchange of functional groups. PMID:24804650

  9. Comparison of electrocoagulation and chemical coagulation for heavy metal removal

    Akbal, F.; Camci, S. [Ondokuz Mayis University, Engineering Faculty, Environmental Engineering Department, Kurupelit, Samsun (Turkey)

    2010-10-15

    Copper (Cu), chromium (Cr), and nickel (Ni) removal from metal plating wastewater by electrocoagulation and chemical coagulation was investigated. Chemical coagulation was performed using either aluminum sulfate or ferric chloride, whereas electrocoagulation was done in an electrolytic cell using aluminum or iron electrodes. By chemical coagulation, Cu-, Cr-, and Ni-removal of 99.9 % was achieved with aluminum sulfate and ferric chloride dosages of 500, 1000, and 2000 mg L{sup -1}, respectively. Removal of metals by electrocoagulation was affected by the electrode material, wastewater pH, current density, number of electrodes, and electrocoagulation time. Electrocoagulation with iron electrodes at a current density of 10 mA cm{sup -2}, electrocoagulation time of 20 min, and pH 3.0 resulted in 99.9 % Cu-, 99.9 % Cr-, and 98 % Ni-removal. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  10. Removal of heavy metals from aqueous solution by Carrot residues

    The removal of Copper(II), Zinc(II), and Chromium (III) from wastewater by carrot residues was investigated to evaluate cation exchange capacity. The effects of solution P H and co-ions were studied in batch experiments. Adsorption equilibria were initially rapidly established, and then decreased markedly after 10 min. Column experiments were carried out in a glass column filled with carrot residues to evaluate the metal removal capacity. The influences of the feed concentration and feed rate were also studied in order to compare the dynamic capacity for metal binding in different feed concentrations

  11. An optimised method for electrodialytic removal of heavy metals from harbour sediments

    Pedersen, Kristine B.; Jensen, Pernille Erland; Ottosen, Lisbeth M.;

    2015-01-01

    A 2-compartment electrodialytic cell set-up for treatment of solid materials has in many respects proven superior to other types of cells in removing heavy metals from sediments. Most notably, remediation times were shorter, energy consumption was lower and higher removal efficiencies were observed....... By employing m1ultivariate modelling and investigating additional experimental variables, the relative importance of variables effecting remediation was determined and response surfaces for heavy metal removal were calculated. Employing optimal conditions it was possible to remove targeted metals (Pb......, Cu, Zn), by 73-96 %, and remediation objectives could be met in a large region of the studied experimental domain....

  12. Heavy Metal Removal by Chitosan and Chitosan Composite

    Radiation grafting of diethyl aminoethyl methacrylate (DEAEMA) on chitosan to impart ion exchange properties and to be used for the separation of metal ions from waste water, was carried out. The effect of experimental conditions such as monomer concentration and the radiation dose on grafting were studied. On using chitosan, grafted chitosan and some chitosan composites in metal ion removal they show high up-take capacity for Cu2+ and lower uptake capacities for the other divalent metal ions used (Zn and Co). Competitive study, performed with solutions containing mixture of metal salts, showed high selectivity for Cu2+ than the other metal ion. Limited grafting of DEAEMA polymer -containing specific functional groups-onto the chitosan backbone improves the sorption performance

  13. Removal of Heavy Metal Ions From Aqueous Solutions

    maziar noei

    2014-12-01

    Full Text Available The removal of Zn(II, V(II,  by  silica aerogel has been found to be concentration, , contact time, adsorbent dose and temperature dependent. ion exchange are the major removal mechanisms involved. The adsorption isotherm studies clearly indicated that the adsorptive behaviour of metal ions on silica aerogel  was satisfied. The applicability of the Lagergren kinetic model has also been investigated. Thermodynamic constant (Kad , standard free energy ( ∆G0 ,enthalpy (∆H0 and entropy (∆S0 were calculated for predicting the nature of adsorption

  14. Concurrent removal and accumulation of heavy metals by the three aquatic macrophytes.

    Mishra, Virendra Kumar; Tripathi, B D

    2008-10-01

    Under the present investigation effectiveness of three aquatic macrophytes Pistia stratiotes L. (water lettuce), Spirodela polyrrhiza W. Koch (duckweed) and Eichhornia crassipes were tested for the removal of five heavy metals (Fe, Zn, Cu, Cr and Cd). These plants were grown at three different concentrations (1.0, 2.0 and 5.0mgl(-1)) of metals in laboratory experiment. Result revealed high removal (>90%) of different metals during 15 days experiment. Highest removal was observed on 12th day of experiment, thereafter it decreased. Results revealed E. crassipes as the most efficient for the removal of selected heavy metals followed by P. stratiotes and S. polyrrhiza. Results from analysis confirmed the accumulation of different metals within the plant and a corresponding decrease of metals in the water. Significant correlations between metal concentration in final water and macrophytes were obtained. Plants have accumulated heavy metals in its body without the production of any toxicity or reduction in growth. Selected plants shown a wide range of tolerance to all of the selected metals and therefore can be used for large scale removal of heavy metals from waste water. PMID:18296043

  15. Application of Iron Oxide Nanomaterials for the Removal of Heavy Metals

    Pragnesh N. Dave

    2014-01-01

    Full Text Available In the 21st century water polluted by heavy metal is one of the environment problems. Various methods for removal of the heavy metal ions from the water have extensively been studied. Application of iron oxide nanaparticles based nanomaterials for removal of heavy metals is well-known adsorbents for remediation of water. Due to its important physiochemical property, inexpensive method and easy regeneration in the presence of external magnetic field make them more attractive toward water purification. Surface modification strategy of iron oxide nanoparticles is also used for the remediation of water increases the efficiency of iron oxide for the removal of the heavy metal ions from the aqueous system.

  16. Heavy metal removal from MSS fly ash by thermal and chlorination treatments

    Liu, Jingyong; Chen, Jiacong; Huang, Limao

    2015-11-01

    The thermal behavior of heavy metals in the co-incineration of municipal solid waste-sludge incinerator fly ash (MSS fly ash) was studied using a laboratory-scale tube furnace. The results indicate that without the addition of chlorinating agents, temperature was an important parameter and had significantly influenced on heavy metal removal, whereas the residence time had a weak effect. Between 900 and 1000 °C for 60 to 300 min, heavy metals reacted with chloride-inherent in the fly ash, and approximately 80 to 89% of Pb, 48% to 56% of Cd, 27% to 36% of Zn and 6% to 24% of Cu were removed. After the adding chlorinating agents, the evaporation rate of the heavy metals improved dramatically, where the evaporation rates of Cu and Zn were larger than that of Pb and Cd. As the amount of added chlorinating agents increased, the removal rate of heavy metals increased. However, the effect of the type of chlorinating agent on the chlorination of heavy metals differed considerably, where NaCl had the weakest effect on the removal rate of Cu, Cd and Zn. In terms of resource recovery and decontamination, MgCl2 and CaCl2 are the best choices due to their efficient removal of Zn.

  17. Acidification of Harbour sediment and removal of heavy metals induced by water splitting in electrodialytic remediation

    Nystrøm, Gunvor Marie; Ottosen, Lisbeth M.; Villumsen, Arne

    2005-01-01

    Harbor sediments are often contaminated with heavy metals, which can be removed by electrodialytic remediation. Water splitting at the anion exchange membrane in contact with the contaminated material in electrodialytic remediation is highly important for the removal of heavy metals. Here it was...... investigated how acidification caused by water splitting at the anion exchange membrane during electrodialytic remediation of contaminated harbor sediment and hence the metal removal, was influenced by different experimental conditions. Two different experimental cells were tested, where the number of...... sediment was acidified, the voltage decreased and electrical conductivity increased. After 5 days of remediation the sediment was acidified at the chosen current density (1 mA/cm(2)) and the main metal removal was observed shortly after. Thus it was crucial for the metal removal that the sediment was fully...

  18. Removal of heavy metals from kaolin using an upward electrokinetic soil remedial (UESR) technology.

    Wang, Jing-Yuan; Huang, Xiang-Jun; Kao, Jimmy C M; Stabnikova, Olena

    2006-08-25

    An upward electrokinetic soil remedial (UESR) technology was proposed to remove heavy metals from contaminated kaolin. Unlike conventional electrokinetic treatment that uses boreholes or trenches for horizontal migration of heavy metals, the UESR technology, applying vertical non-uniform electric fields, caused upward transportation of heavy metals to the top surface of the treated soil. The effects of current density, treatment duration, cell diameter, and different cathode chamber influent (distilled water or 0.01 M nitric acid) were studied. The removal efficiencies of heavy metals positively correlated to current density and treatment duration. Higher heavy metals removal efficiency was observed for the reactor cell with smaller diameter. A substantial amount of heavy metals was accumulated in the nearest to cathode 2 cm layer of kaolin when distilled water was continuously supplied to the cathode chamber. Heavy metals accumulated in this layer of kaolin can be easily excavated and disposed off. The main part of the removed heavy metals was dissolved in cathode chamber influent and moved away with cathode chamber effluent when 0.01 M nitric acid was used, instead of distilled water. Energy saving treatment by UESR technology with highest metal removal efficiencies was provided by two regimes: (1) by application of 0.01 M nitric acid as cathode chamber influent, cell diameter of 100 mm, duration of 18 days, and constant voltage of 3.5 V (19.7 k Wh/m(3) of kaolin) and (2) by application of 0.01 M nitric acid as cathode chamber influent, cell diameter of 100 cm, duration of 6 days, and constant current density of 0.191 mA/cm(2) (19.1 k Wh/m(3) of kaolin). PMID:16504386

  19. A highly efficient and selective polysilsesquioxane sorbent for heavy metal removal

    Duan, Xiaonan

    2012-02-29

    Suited for heavy stuff: An efficient mesoporous sorbent based on a pure ethylendiamine-bridged polysilsesquioxane is presented. This material, with both a high amine loading and a high surface area, is applied for heavy metal ion removal. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Understanding the factors influencing the removal of heavy metals in urban stormwater runoff.

    Maniquiz-Redillas, Marla C; Kim, Lee-Hyung

    2016-01-01

    In this research, an infiltration trench equipped with an extensive pretreatment and filter bed consisting of woodchip, sand and gravel was utilized as a low impact development technique to manage stormwater runoff from a highly impervious road with particular emphasis on heavy metal removal. Findings revealed that the major factors influencing the removal of heavy metals were the concentration of the particulate matters and heavy metals in runoff, runoff volume and flow rates. The reduction of heavy metals was enhanced by sedimentation of particulates through pretreatment. Fine particles (filter media were important design considerations. Sediment was most highly attached on the surface area of woodchip than to other filter media like sand, gravel and geotextile. It is suggested that maintenance must be performed after the end of the winter season wherein high sediment rate was observed to maintain the efficiency of the treatment system. PMID:27332837

  1. Effects of pulse current on energy consumption and removal of heavy metals during electrodialytic soil remediation

    Sun, Tian R.; Ottosen, Lisbeth M.

    2012-01-01

    exchange membrane was the major contributor of energy consumption, and the pulse current could decrease the voltage drop of this part effectively. The overall removal of heavy metals in soil 1 (6–54%) was much higher than soil 2 (1–17%) due to the different acidification process and chemical speciation of...... heavy metals reflected by sequential extraction analysis. Among all experiments, the highest removal efficiency occurred in pulse current experiment of soil 1, where 54% of Cu and 30% of As were removed.......The aims of this paper were to investigate the possibility for energy saving when using a pulsed electric field during electrodialytic soil remediation (EDR) and the effect of the pulsed current on removal of heavy metals. Eight experiments with constant and pulse current in the different...

  2. Heavy metal removal from sewage sludge ash by thermochemical treatment with gaseous hydrochloric acid.

    Vogel, Christian; Adam, Christian

    2011-09-01

    Sewage sludge ash (SSA) is a suitable raw material for fertilizers due to its high phosphorus (P) content. However, heavy metals must be removed before agricultural application and P should be transferred into a bioavailable form. The utilization of gaseous hydrochloric acid for thermochemical heavy metal removal from SSA at approximately 1000 °C was investigated and compared to the utilization of alkaline earth metal chlorides. The heavy metal removal efficiency increased as expected with higher gas concentration, longer retention time and higher temperature. Equivalent heavy metal removal efficiency were achieved with these different Cl-donors under comparable conditions (150 g Cl/kg SSA, 1000 °C). In contrast, the bioavailability of the P-bearing compounds present in the SSA after thermal treatment with gaseous HCl was not as good as the bioavailability of the P-bearing compounds formed by the utilization of magnesium chloride. This disadvantage was overcome by mixing MgCO(3) as an Mg-donor to the SSA before thermochemical treatment with the gaseous Cl-donor. A test series under systematic variation of the operational parameters showed that copper removal is more depending on the retention time than the removal of zinc. Zn-removal was declined by a decreasing ratio of the partial pressures of ZnCl(2) and water. PMID:21819089

  3. Evaluation of Heavy Metal Removal from Wastewater in a Modified Packed Bed Biofilm Reactor

    Shohreh Azizi; Ilunga Kamika; Memory Tekere

    2016-01-01

    For the effective application of a modified packed bed biofilm reactor (PBBR) in wastewater industrial practice, it is essential to distinguish the tolerance of the system for heavy metals removal. The industrial contamination of wastewater from various sources (e.g. Zn, Cu, Cd and Ni) was studied to assess the impacts on a PBBR. This biological system was examined by evaluating the tolerance of different strengths of composite heavy metals at the optimum hydraulic retention time (HRT) of 2 h...

  4. Removal of Heavy Metals from Aqueous Solution using Clinoptilolite and Stilbite

    Golomeova, Mirjana; Zendelska, Afrodita; Blažev, Krsto; Krstev, Boris; Golomeov, Blagoj

    2014-01-01

    Heavy metals are highly toxic and they must be removed from the polluted streams. Аdsorption by zeolites is currently considered to be very suitable for wastewater treatment because of its simplicity and cost effectiveness. The aim of this investigation was to compare adsorption efficiency of heavy metals (Cu, Zn, Mn and Pb) from aqueous solution using two different types of natural zeolite: clinoptilolite from Bulgaria and stilbite from Macedonia. The obtained information will be basis for f...

  5. Silica coated magnetite nanoparticles for removal of heavy metal ions from polluted waters

    Dash, Monika

    2013-01-01

    Magnetic removal of Hg2+ and other heavy metal ions like Cd2+, Pb2+ etc. using silica coated magnetite particles from polluted waters is a current topic of active research to provide efficient water recycling and long term high quality water. The technique used to study the bonding characteristics of such kind of nanoparticles with the heavy metal ions is a very sensitive hyperfine specroscopy technique called the perturbed angular correlation technique (PAC).

  6. REMOVAL OF HEAVY METALS FROM INDUSTRIAL WASTEWATERS USING INSOLUBLE STARCH XANTHATE

    The Northern Regional Research Center developed an effective process to remove heavy metals from wastewaters of two nonferrous metal industries and insoluble starch xanthate (ISX). The study included bench-scale evaluation of wastewaters from two lead battery and one brass mill w...

  7. USEBILITY OF HYDROGELS IN ADSORPTION TECHNOLOGHY FOR REMOVAL OF HEAVY METAL AND DYE

    AÇIKEL Safiye Meriç

    2016-05-01

    Full Text Available Heavy metals and Dyes are very toxic and nonbiodegradable in waste waters to cause adverse health effects in human body and to induce irreversible pollution. Adsorption offers many potential advantages for removal of toxic heavy metals being flexibility in design and operation, high-quality treated effluent, reversible nature for multiple uses, and many commercially available adsorbent materials, such as activated carbon, zeolite, clay, sawdust, bark, biomass, lignin, chitosan and other polymer adsorbents. Compared to conventional adsorbent materials above, hydrogelbased adsorbents recently have attracted special attention to their highly potential for effective removal of heavy metals and dyes. Hydrogels are named “Hydrophilic Polymer” because of care for water. Hydrogels is not solved in water; however they have been swollen to their balance volume. Because of this swell behavior, they can adsorb big quantity of water in this structure. So they can term of “three sized polymers” due to protect their existing shape [9]. Hydrogels with porous structures and chemically-responsive functional groups, enable to readily capture metal ions and dyes from wastewater. Hydrogels with porous structures and chemically-responsive functional groups, enable to readily capture metal ions and dyes from wastewater. In adsorption applications, hydrogels are used in water purification, heavy metal/dying removing, controlled fertilizer released, ion exchange applications, chromatographic applications, dilute extractions, waste water treatments. This article general inform about usage of hydrogels in Dye and Heavy Metal adsorption.

  8. Literature review on the use of bioaccumulation for heavy metal removal and recovery. Volume 2

    Benemann, J.R. [Benemann (J.R.), Pinole, CA (United States); Wilde, E.W. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1991-02-01

    Bioaccumulation of metals by microbes -- `` bioremoval`` -- is a powerful new technology for the concentration, recovery, and removal of toxic heavy metals and radionuclides from waste streams and contaminated environments. Algae are particularly well suited for metal bioremoval. A recent commercial application of bioremoval utilizes inert (dead) immobilized microalgae biomass as ion exchange materials for the removal of heavy metals from industrial waste waters. Also, living microalgal cultures have been used to remove metals from mine effluents. Microbial cells and biomass can bioaccumulate metals and radionuclides by a large variety of mechanisms, both dependent and independent of cell metabolism. Microbial cell walls can act as ion exchange and metal complexation agents. Heavy metals can precipitate and even crystallize on cell surfaces. Metabolically produced hydrogen sulfide or other metabolic products can bioprecipitate heavy metals. Many microbes produce both intra- and extracellular metal complexing agents which could be considered in practical metal removal processes. Bioremoval processes are greatly affected by the microbial species and even strain used, pH, redox potential, temperature, and other conditions under which the microbes are grown. Development of practical applications of bioremoval requires applies research using the particular waste solutions to be treated, or close simulations thereof. From a practical perspective, the selection of the microbial biomass and the process for contacting the microbial biomass with the metal containing solutions are the key issues. Much of the recent commercial R&D has emphasized commercially available, inert, microbial biomass sources as these can be acquired in sufficient quantities at affordable costs. The fundamental research and practical applications of bioaccumulation by microalgae suggests these organisms warrant a high priority in the development of advanced bioremoval processes.

  9. Literature review on the use of bioaccumulation for heavy metal removal and recovery

    Benemann, J.R. (Benemann (J.R.), Pinole, CA (United States)); Wilde, E.W. (Westinghouse Savannah River Co., Aiken, SC (United States))

    1991-02-01

    Bioaccumulation of metals by microbes -- bioremoval'' -- is a powerful new technology for the concentration, recovery, and removal of toxic heavy metals and radionuclides from waste streams and contaminated environments. Algae are particularly well suited for metal bioremoval. A recent commercial application of bioremoval utilizes inert (dead) immobilized microalgae biomass as ion exchange materials for the removal of heavy metals from industrial waste waters. Also, living microalgal cultures have been used to remove metals from mine effluents. Microbial cells and biomass can bioaccumulate metals and radionuclides by a large variety of mechanisms, both dependent and independent of cell metabolism. Microbial cell walls can act as ion exchange and metal complexation agents. Heavy metals can precipitate and even crystallize on cell surfaces. Metabolically produced hydrogen sulfide or other metabolic products can bioprecipitate heavy metals. Many microbes produce both intra- and extracellular metal complexing agents which could be considered in practical metal removal processes. Bioremoval processes are greatly affected by the microbial species and even strain used, pH, redox potential, temperature, and other conditions under which the microbes are grown. Development of practical applications of bioremoval requires applies research using the particular waste solutions to be treated, or close simulations thereof. From a practical perspective, the selection of the microbial biomass and the process for contacting the microbial biomass with the metal containing solutions are the key issues. Much of the recent commercial R D has emphasized commercially available, inert, microbial biomass sources as these can be acquired in sufficient quantities at affordable costs. The fundamental research and practical applications of bioaccumulation by microalgae suggests these organisms warrant a high priority in the development of advanced bioremoval processes.

  10. Literature review on the use of bioaccumulation for heavy metal removal and recovery

    Bioaccumulation of metals by microbes -- '' bioremoval'' -- is a powerful new technology for the concentration, recovery, and removal of toxic heavy metals and radionuclides from waste streams and contaminated environments. Algae are particularly well suited for metal bioremoval. A recent commercial application of bioremoval utilizes inert (dead) immobilized microalgae biomass as ion exchange materials for the removal of heavy metals from industrial waste waters. Also, living microalgal cultures have been used to remove metals from mine effluents. Microbial cells and biomass can bioaccumulate metals and radionuclides by a large variety of mechanisms, both dependent and independent of cell metabolism. Microbial cell walls can act as ion exchange and metal complexation agents. Heavy metals can precipitate and even crystallize on cell surfaces. Metabolically produced hydrogen sulfide or other metabolic products can bioprecipitate heavy metals. Many microbes produce both intra- and extracellular metal complexing agents which could be considered in practical metal removal processes. Bioremoval processes are greatly affected by the microbial species and even strain used, pH, redox potential, temperature, and other conditions under which the microbes are grown. Development of practical applications of bioremoval requires applies research using the particular waste solutions to be treated, or close simulations thereof. From a practical perspective, the selection of the microbial biomass and the process for contacting the microbial biomass with the metal containing solutions are the key issues. Much of the recent commercial R ampersand D has emphasized commercially available, inert, microbial biomass sources as these can be acquired in sufficient quantities at affordable costs. The fundamental research and practical applications of bioaccumulation by microalgae suggests these organisms warrant a high priority in the development of advanced bioremoval processes

  11. Application of Electrochemical Process in Removal of Heavy Metals from Landfill Leachate

    Mostafaii Gh.1 PhD,

    2016-08-01

    Full Text Available Aims Municipal landfill leachate contains high concentrations of heavy metals, organics, ammonia. The efficeincy of electrochemically removal of heavy metals from landfill leachate was studied. Materials & Methods The leachate was obtained from Kahrizak landfill in south of Tehran. The experiments were carried out by batch process. The 2liter batch reactor was made of glass. There were eight anodes and cathodes electrodes. The electrodes were placed vertically parallel to each other and they were connected to a digital DC power supply. The pH and conductivity were adjusted to a desirable value using NaOH or H2SO4, and NaCl. All the runs were performed at constant temperature of 25°C. In each run, 1.5liter of the leachate was placed into the electrolytic cell. Samples were extracted every 10min and then filtered through a mixed cellulose acetate membrane (0.42μm. The amount of Lead, Zinc and Nickel removal was measured at pH=7 and in current density of 0.5, 0.75, and 1A. Findings When current density and time reaction increased, removal efficiency of heavy metals such as Lead, Zinc and Nickel increased. At initial pH=7, density 1A and reaction time= 60min, Lead, Nickel and Zinc were removed up to 86, 93 and 95%, respectively. Conclusion Electrochemical process can be proposed as a suitable technique to remove heavy metal from landfill leachate.

  12. Performance evaluation of intermediate cover soil barrier for removal of heavy metals in landfill leachate.

    Suzuki, Kazuyuki; Anegawa, Aya; Endo, Kazuto; Yamada, Masato; Ono, Yusaku; Ono, Yoshiro

    2008-11-01

    This pilot-scale study evaluated the use of intermediate cover soil barriers for removing heavy metals in leachate generated from test cells for co-disposed fly ash from municipal solid waste incinerators, ash melting plants, and shredder residue. Cover soil barriers were mixtures of Andisol (volcanic ash soil), waste iron powder, (grinder dust waste from iron foundries), and slag fragments. The cover soil barriers were installed in the test cells' bottom layer. Sorption/desorption is an important process in cover soil bottom barrier for removal of heavy metals in landfill leachate. Salt concentrations such as those of Na, K, and Ca in leachate were extremely high (often greater than 30 gL(-1)) because of high salt content in fly ash from ash melting plants. Concentrations of all heavy metals (nickel, manganese, copper, zinc, lead, and cadmium) in test cell leachates with a cover soil barrier were lower than those of the test cell without a cover soil barrier and were mostly below the discharge limit, probably because of dilution caused by the amount of leachate and heavy metal removal by the cover soil barrier. The cover soil barriers' heavy metal removal efficiency was calculated. About 50% of copper, nickel, and manganese were removed. About 20% of the zinc and boron were removed, but lead and cadmium were removed only slightly. Based on results of calculation of the Langelier saturation index and analyses of core samples, the reactivity of the cover soil barrier apparently decreases because of calcium carbonate precipitation on the cover soil barriers' surfaces. PMID:18842283

  13. Heavy metals removal from aqueous solutions and wastewaters by using various byproducts.

    Shaheen, Sabry M; Eissa, Fawzy I; Ghanem, Khaled M; Gamal El-Din, Hala M; Al Anany, Fathia S

    2013-10-15

    Water contamination with heavy metals (HM) represents a potential threat to humans, animals and plants, and thus removal of these metals from contaminated waters has received increasing attention. The present study aimed to assess the efficiency of some low cost sorbents i.e., chitosan (CH), egg shell (ES), humate potassium (HK), and sugar beet factory lime (SBFL) for removal of cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) from wastewaters. For this purpose batch equilibrium experiments were conducted with aqueous solutions containing various concentrations of the metals and sorbents in a mono-metal and competitive sorption system. Sorption isotherms were developed, and sorption parameters were determined. The potential applicability of the tested sorbents in the removal of Cd, Cu, and Zn from contaminated wastewaters was also investigated by equilibrating different sorbents and water ratios. Chitosan expressed the highest affinity for the metals followed by SBFL, ES, and HK. Nearly 100% of the metals were removed from aqueous solutions with the lowest initial metal concentrations by the sorbents especially CH and SBFL. However, the sorption efficiency decreased as the initial metal concentrations increased. Competition among the four metals changed significantly their distribution coefficient (Kd) values with the sorbents. The selectivity sequence of the metals was: Pb > Cu > Zn > Cd. The metal removal from the wastewaters varied from 72, 69, and 60 to nearly 100% for Cd, Cu and Zn, respectively. The efficiency of the studied byproducts in removing metals from the wastewaters differed based on the source of contamination and metal concentrations. Cadmium removal percentages by HK and CH were higher than SBFL and ES. The HK and CH exhibited the highest removal percentage of Cu from water with high concentrations. The SBFL and ES revealed the highest removal percentage of Zn from water with high concentrations. The results, demonstrate a high potential

  14. Simultaneous heavy metals removal and municipal sewage sludge dewaterability improvement in bioleaching processes by various inoculums.

    Shi, Chaohong; Zhu, Nengwu; Shang, Ru; Kang, Naixin; Wu, Pingxiao

    2015-11-01

    The heavy metals content and dewaterability of municipal sewage sludge (MSS) are important parameters affecting its subsequent disposal and land application. Six kinds of inoculums were prepared to examine the characteristics of heavy metals removal and MSS dewaterability improvement in bioleaching processes. The results showed that Cu, Zn and Cd bioleaching efficiencies (12 days) were 81-91, 87-93 and 81-89%, respectively, which were significantly higher than those of Fe-S control (P bioleaching boosted by the prepared inoculums could also significantly enhance MSS dewaterability (P bioleaching for heavy metals removal and dewaterability improvement. It also suggested that the synergy of sulfur/ferrous-oxidizing bacteria (SFOB) enriched from AMD and the cooperation of exogenous and indigenous SFOB significantly promoted bioleaching efficiencies. PMID:26271772

  15. The use of biosorbents for heavy metals removal from aqueous media

    Biomaterials, which could be adsorbed heavy metals, such bacteria, algae, yeasts, fungi and agricultural waste, is called Biomass. Recently, they are widely used for heavy metal removal from aqueous media, due to their large available quantities, low cost and good performance. The biosorbent, unlike mono functional ion exchange resins, contains variety of functional sites including carboxyl, imidazole, sulphydryl, amino, phosphate, sulfate, thioether, phenol, carbonyl, amide and hydroxyl moieties. In this paper, the biosorbents word widely and nationally used for heavy metal removal were reviewed. Their biosorption performance, their pretreatment and modification, aiming to improve their sorption capacity, and regeneration/reuse was introduced and evaluated. The potential application of biosorption and biosorbents was discussed. (author)

  16. A review on progress of heavy metal removal using adsorbents of microbial and plant origin.

    Srivastava, Shalini; Agrawal, S B; Mondal, M K

    2015-10-01

    Heavy metals released into the water bodies and on land surfaces by industries are highly toxic and carcinogenic in nature. These heavy metals create serious threats to all the flora and fauna due to their bioaccumulatory and biomagnifying nature at various levels of food chain. Existing conventional technologies for heavy metal removal are witnessing a downfall due to high operational cost and generation of huge quantity of chemical sludge. Adsorption by various adsorbents appears to be a potential alternative of conventional technologies. Its low cost, high efficiency, and possibility of adsorbent regeneration for reuse and recovery of metal ions for various purposes have allured the scientists to work on this technique. The present review compiles the exhaustive information available on the utilization of bacteria, algae, fungi, endophytes, aquatic plants, and agrowastes as source of adsorbent in adsorption process for removal of heavy metals from aquatic medium. During the last few years, a lot of work has been conducted on development of adsorbents after modification with various chemical and physical techniques. Adsorption of heavy metal ions is a complex process affected by operating conditions. As evident from the literature, Langmuir and Freundlich are the most widely used isotherm models, while pseudo first and second order are popularly studied kinetic models. Further, more researches are required in continuous column system and its practical application in wastewater treatment. PMID:26315592

  17. Enhanced removal of heavy metals in primary treatment using coagulation and flocculation.

    Johnson, Pauline D; Girinathannair, Padmanabhan; Ohlinger, Kurt N; Ritchie, Stephen; Teuber, Leah; Kirby, Jason

    2008-05-01

    The goal of this study was to determine the removal efficiencies of chromium, copper, lead, nickel, and zinc from raw wastewater by chemically enhanced primary treatment (CEPT) and to attain a total suspended solids removal goal of 80%. Operating parameters and chemical doses were optimized by bench-scale tests. Locally obtained raw wastewater samples were spiked with heavy metal solutions to obtain representative concentrations of metals in wastewater. Jar tests were conducted to compare the metals removal efficiencies of the chemical treatment options using ferric chloride, alum, and anionic polymer. The results obtained were compared with those from other studies. It was concluded that CEPT using ferric chloride and anionic polymer is more effective than CEPT using alum for metals removal. The CEPT dosing of 40 mg/L ferric chloride and 0.5 mg/L polymer enhanced heavy metals removal efficiencies by over 200% for chromium, copper, zinc, and nickel and 475% for lead, compared with traditional primary treatment. Efficient metals capture during CEPT can result in increased allowable headworks loadings or lower metal levels in the outfall. PMID:18605386

  18. Graphene-Based Microbots for Toxic Heavy Metal Removal and Recovery from Water.

    Vilela, Diana; Parmar, Jemish; Zeng, Yongfei; Zhao, Yanli; Sánchez, Samuel

    2016-04-13

    Heavy metal contamination in water is a serious risk to the public health and other life forms on earth. Current research in nanotechnology is developing new nanosystems and nanomaterials for the fast and efficient removal of pollutants and heavy metals from water. Here, we report graphene oxide-based microbots (GOx-microbots) as active self-propelled systems for the capture, transfer, and removal of a heavy metal (i.e., lead) and its subsequent recovery for recycling purposes. Microbots' structure consists of nanosized multilayers of graphene oxide, nickel, and platinum, providing different functionalities. The outer layer of graphene oxide captures lead on the surface, and the inner layer of platinum functions as the engine decomposing hydrogen peroxide fuel for self-propulsion, while the middle layer of nickel enables external magnetic control of the microbots. Mobile GOx-microbots remove lead 10 times more efficiently than nonmotile GOx-microbots, cleaning water from 1000 ppb down to below 50 ppb in 60 min. Furthermore, after chemical detachment of lead from the surface of GOx-microbots, the microbots can be reused. Finally, we demonstrate the magnetic control of the GOx-microbots inside a microfluidic system as a proof-of-concept for automatic microbots-based system to remove and recover heavy metals. PMID:26998896

  19. Removal of heavy metals from fly ash leachate using combined bioelectrochemical systems and electrolysis

    Highlights: • Heavy metals removal from MSWI fly ash with BES and electrolysis was confirmed. • 98.5% of Cu(II), 95.4% of Zn(II) and 98.1% of Pb(II) removal were achieved in reactors. • BESs can remove some heavy metals in fly ash with energy saving. -- Abstract: Based on environmental and energetic analysis, a novel combined approach using bioelectrochemical systems (BES) followed by electrolysis reactors (ER) was tested for heavy metals removal from fly ash leachate, which contained high detectable levels of Zn, Pb and Cu according to X-ray diffraction analysis. Acetic acid was used as the fly ash leaching agent and tested under various leaching conditions. A favorable condition for the leaching process was identified to be liquid/solid ratio of 14:1 (w/w) and leaching duration 10 h at initial pH 1.0. It was confirmed that the removal of heavy metals from fly ash leachate with the combination of BESs and ER is feasible. The metal removal efficiency was achieved at 98.5%, 95.4% and 98.1% for Cu(II), Zn(II), and Pb(II), respectively. Results of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) indicated that Cu(II) was reduced and recovered mainly as metal Cu on cathodes related to power production, while Zn(II) and Pb(II) were not spontaneously reduced in BESs without applied voltage and basically electrolyzed in the electrolysis reactors

  20. Effect of solids concentration on removal of heavy metals from mine tailings via bioleaching

    Liu Yunguo [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China)]. E-mail: axore@163.com; Zhou Ming [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Zeng Guangming [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Li Xin [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Xu Weihua [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Fan Ting [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China)

    2007-03-06

    Mining of mineral ore and disposal of resulting waste tailings pose a significant risk to the surrounding environment. The objective of this work is to demonstrate the feasibility to remove heavy metals from mine tailings with the use of bioleaching and meanwhile to investigate the effect of solids concentration on removal of heavy metals from mine tailings by indigenous sulfur-oxidizing bacteria and the transformation of heavy metal forms after the bioleaching process. This work showed the laboratory results of bioleaching experiments on Pb-Zn-Cu mine tailings. The results showed that 98.08% Zn, 96.44% Cu, and 43.52% Pb could be removed from mine tailings by the bioleaching experiment after 13 days at 1% (w/v) solids concentration and the rates of pH reduction, ORP rise and sulfate production were reduced with the increase of solids concentration, due to the buffering capacity of mine tailing solids. The results also indicated that solid concentration 1% was found to be best to bacterial activity and metal solubilization of the five solids concentration tested (1%, 2%, 5%, 8% and 10%) under the chosen experimental conditions. In addition, the bioleaching had a significant impact on changes in partitioning of heavy metals.

  1. Effect of solids concentration on removal of heavy metals from mine tailings via bioleaching

    Mining of mineral ore and disposal of resulting waste tailings pose a significant risk to the surrounding environment. The objective of this work is to demonstrate the feasibility to remove heavy metals from mine tailings with the use of bioleaching and meanwhile to investigate the effect of solids concentration on removal of heavy metals from mine tailings by indigenous sulfur-oxidizing bacteria and the transformation of heavy metal forms after the bioleaching process. This work showed the laboratory results of bioleaching experiments on Pb-Zn-Cu mine tailings. The results showed that 98.08% Zn, 96.44% Cu, and 43.52% Pb could be removed from mine tailings by the bioleaching experiment after 13 days at 1% (w/v) solids concentration and the rates of pH reduction, ORP rise and sulfate production were reduced with the increase of solids concentration, due to the buffering capacity of mine tailing solids. The results also indicated that solid concentration 1% was found to be best to bacterial activity and metal solubilization of the five solids concentration tested (1%, 2%, 5%, 8% and 10%) under the chosen experimental conditions. In addition, the bioleaching had a significant impact on changes in partitioning of heavy metals

  2. Evaluation of Heavy Metal Removal from Wastewater in a Modified Packed Bed Biofilm Reactor.

    Azizi, Shohreh; Kamika, Ilunga; Tekere, Memory

    2016-01-01

    For the effective application of a modified packed bed biofilm reactor (PBBR) in wastewater industrial practice, it is essential to distinguish the tolerance of the system for heavy metals removal. The industrial contamination of wastewater from various sources (e.g. Zn, Cu, Cd and Ni) was studied to assess the impacts on a PBBR. This biological system was examined by evaluating the tolerance of different strengths of composite heavy metals at the optimum hydraulic retention time (HRT) of 2 hours. The heavy metal content of the wastewater outlet stream was then compared to the source material. Different biomass concentrations in the reactor were assessed. The results show that the system can efficiently treat 20 (mg/l) concentrations of combined heavy metals at an optimum HRT condition (2 hours), while above this strength there should be a substantially negative impact on treatment efficiency. Average organic reduction, in terms of the chemical oxygen demand (COD) of the system, is reduced above the tolerance limits for heavy metals as mentioned above. The PBBR biological system, in the presence of high surface area carrier media and a high microbial population to the tune of 10 000 (mg/l), is capable of removing the industrial contamination in wastewater. PMID:27186636

  3. Evaluation of Heavy Metal Removal from Wastewater in a Modified Packed Bed Biofilm Reactor.

    Shohreh Azizi

    Full Text Available For the effective application of a modified packed bed biofilm reactor (PBBR in wastewater industrial practice, it is essential to distinguish the tolerance of the system for heavy metals removal. The industrial contamination of wastewater from various sources (e.g. Zn, Cu, Cd and Ni was studied to assess the impacts on a PBBR. This biological system was examined by evaluating the tolerance of different strengths of composite heavy metals at the optimum hydraulic retention time (HRT of 2 hours. The heavy metal content of the wastewater outlet stream was then compared to the source material. Different biomass concentrations in the reactor were assessed. The results show that the system can efficiently treat 20 (mg/l concentrations of combined heavy metals at an optimum HRT condition (2 hours, while above this strength there should be a substantially negative impact on treatment efficiency. Average organic reduction, in terms of the chemical oxygen demand (COD of the system, is reduced above the tolerance limits for heavy metals as mentioned above. The PBBR biological system, in the presence of high surface area carrier media and a high microbial population to the tune of 10 000 (mg/l, is capable of removing the industrial contamination in wastewater.

  4. Heavy metal removal from municipal solid waste fly ash by chlorination and thermal treatment

    Municipal solid waste (MSW) fly ash is classified as a hazardous material because it contains high amounts of heavy metals. For decontamination, MSW fly ash is first mixed with alkali or alkaline earth metal chlorides (e.g. calcium chloride) and water, and then the mixture is pelletized and treated in a rotary reactor at about 1000deg. C. Volatile heavy metal compounds are formed and evaporate. In this paper, the effect of calcium chloride addition, gas velocity, temperature and residence time on the separation of heavy metals are studied. The fly ash was sampled at the waste-to-energy plant Fernwaerme Wien/Spittelau (Vienna, Austria). The results were obtained from batch tests performed in an indirectly heated laboratory-scale rotary reactor. More than 90% of Cd and Pb and about 60% of Cu and 80% of Zn could be removed in the experiments.

  5. Heavy metal removal from municipal solid waste fly ash by chlorination and thermal treatment.

    Nowak, B; Pessl, A; Aschenbrenner, P; Szentannai, P; Mattenberger, H; Rechberger, H; Hermann, L; Winter, F

    2010-07-15

    Municipal solid waste (MSW) fly ash is classified as a hazardous material because it contains high amounts of heavy metals. For decontamination, MSW fly ash is first mixed with alkali or alkaline earth metal chlorides (e.g. calcium chloride) and water, and then the mixture is pelletized and treated in a rotary reactor at about 1000 degrees C. Volatile heavy metal compounds are formed and evaporate. In this paper, the effect of calcium chloride addition, gas velocity, temperature and residence time on the separation of heavy metals are studied. The fly ash was sampled at the waste-to-energy plant Fernwärme Wien/Spittelau (Vienna, Austria). The results were obtained from batch tests performed in an indirectly heated laboratory-scale rotary reactor. More than 90% of Cd and Pb and about 60% of Cu and 80% of Zn could be removed in the experiments. PMID:20356672

  6. Heavy metal removal from municipal solid waste fly ash by chlorination and thermal treatment

    Nowak, B., E-mail: benedikt.nowak@tuwien.ac.at [Institute of Chemical Engineering/Vienna University of Technology, Getreidemarkt 9/166, A-1060 Vienna (Austria); Pessl, A. [Institute of Chemical Engineering/Vienna University of Technology, Getreidemarkt 9/166, A-1060 Vienna (Austria); Aschenbrenner, P. [Institute for Water Quality, Resource and Waste Management/Vienna University of Technology, Karlsplatz 13/226, A-1040 Vienna (Austria); Szentannai, P. [Institute of Chemical Engineering/Vienna University of Technology, Getreidemarkt 9/166, A-1060 Vienna (Austria); Mattenberger, H. [ASH DEC Umwelt AG, Donaufelderstrasse 101/4/5, A-1210 Vienna (Austria); Rechberger, H. [Institute for Water Quality, Resource and Waste Management/Vienna University of Technology, Karlsplatz 13/226, A-1040 Vienna (Austria); Hermann, L. [ASH DEC Umwelt AG, Donaufelderstrasse 101/4/5, A-1210 Vienna (Austria); Winter, F., E-mail: franz.winter@tuwien.ac.at [Institute of Chemical Engineering/Vienna University of Technology, Getreidemarkt 9/166, A-1060 Vienna (Austria)

    2010-07-15

    Municipal solid waste (MSW) fly ash is classified as a hazardous material because it contains high amounts of heavy metals. For decontamination, MSW fly ash is first mixed with alkali or alkaline earth metal chlorides (e.g. calcium chloride) and water, and then the mixture is pelletized and treated in a rotary reactor at about 1000deg. C. Volatile heavy metal compounds are formed and evaporate. In this paper, the effect of calcium chloride addition, gas velocity, temperature and residence time on the separation of heavy metals are studied. The fly ash was sampled at the waste-to-energy plant Fernwaerme Wien/Spittelau (Vienna, Austria). The results were obtained from batch tests performed in an indirectly heated laboratory-scale rotary reactor. More than 90% of Cd and Pb and about 60% of Cu and 80% of Zn could be removed in the experiments.

  7. Comparison of 2-compartment, 3-compartment and stack designs for electrodialytic removal of heavy metals from harbour sediments

    Pedersen, Kristine B.; Ottosen, Lisbeth M.; Jensen, Pernille Erland;

    2015-01-01

    Comparisons of cell and stack designs for the electrodialytic removal of heavy metals from two harbour sediments, were made. Multivariate modelling showed that sediment properties and experimental set-ups had the highest influence on the heavy metal removal indicating that they should be modelled...

  8. Comparison of Amberlite IR 120 and dolomite's performances for removal of heavy metals

    The presence of heavy metals in the environment is major concern due to their toxicity. Contamination of heavy metals in water supplies has steadily increased over the last years as a result of over population and expansion of industrial activities. A strong cation-exchange resin, Amberlite IR 120 and a natural zeolite, dolomite were used for the removal of lead(II) and cadmium(II). The optimum conditions were determined in a batch system as concentration range was between 5 and 100 mg/L, pH range between 1 and 8, contact time between 5 and 90 min, and the amount of adsorbent was from 0.1 to 1 g. A constant stirring speed, 2000 rpm, was chosen during all of the experiments. The optimum conditions were found to be a concentration of 20 mg/L, pH of 5, contact time of 60 min and 0.5 g of adsorbent. Also, for investigation of exchange equilibria different amounts of ion exchange resin and dolomite were contacted with a fixed volume and concentration of a heavy metal bearing solutions. Sorption data have been interpreted in terms of Langmuir and Freundlich equations. The effect of adsorption temperature on the heavy metals adsorption onto dolomite was investigated at three different temperatures (20, 40 and 60 deg. C). Thermodynamic parameters were calculated. The results obtained show that the Amberlite IR 120 strong cation-exchange resin and dolomite performed well for the removal of these heavy metals. As a low cost adsorbent, dolomite can preferable for removal of heavy metals from wastewaters

  9. Removal of Heavy Metals and PAH in Highway Detention Ponds

    Bentzen, Thomas Ruby; Larsen, Torben; Thorndahl, Søren Liedtke;

    2005-01-01

    rainfalls. The modelling will take place in a special version of the MIKE URBAN. The modelling is calibrated and validated on measurements from selected highway catchments. The removal of pollutants in the ponds is studied by local measurements in combination with CFD modelling using the MIKE 21 and MIKE 3...

  10. Physiochemicals and Heavy Metal Removal from Domestic Wastewater via Phycoremediation

    Ab Razak Abdul Rafiq; Sunar Norshuhaila Mohamed; Alias Nurul Azira; Gani Paran; Subramaniam Menega

    2016-01-01

    The common sources of water pollution in Malaysia are domestic sewage and industrial waste. Therefore, domestic wastewater quality effluent should be improved before discharged through the outlets. The alternative method of treatment uses microalgae for water remediation which is known as phycoremediation was applied. This technique is to remove or reduce nutrients and harmful pollutants in domestic wastewater. Thus, objective of the present study is to bioremediate the physiochemical and hea...

  11. Removal of Some Heavy Metals from Wastewater using Radiation- Adsorption Method

    Wastewater containing toxic materials poses a serious environmental problem. Many of the pollutants are not readily biodegradable and complete removal in many cases is a relatively expensive process. On the other hand, incomplete removal is a serious health hazard. In the present study, a try was made to explain the degradation kinetics due to gamma-irradiation and adsorption of some heavy metals: Uranium, Molybdenum, Zirconium, and Vanadium. Factors affecting the process such as concentration, irradiation dose and ph of the solution was studied. Gamma-radiation doses up to 50 kGy did not result in the degradation of the heavy metals. However, as expected gamma radiation resulted in a change in the valency of these heavy metal ions to other oxidation states which may have resulted in less toxicity. Adsorption and ion-exchange purification of the heavy metals onto GAC,Merck Ion Exchangers I, and IV and polymeric membranes showed that GAC has the highest adsorption capacity for all pollutants compared with the ion-exchangers and polymeric membranes which may be due to its very high surface area and high porous nature which causes internal and external distribution within the carbon particle more than it dose in the case of polymeric membranes and ion-exchangers. GAC was followed by the cation exchanger with different percent adsorption according to the type of pollutant and the least removal percent was shown by the polymeric membranes. Also, a study of the affinity of the pollutants towards the different adsorbents was carried out

  12. Chelating capture and magnetic removal of non-magnetic heavy metal substances from soil

    Fan, Liren; Song, Jiqing; Bai, Wenbo; Wang, Shengping; Zeng, Ming; Li, Xiaoming; Zhou, Yang; Li, Haifeng; Lu, Haiwei

    2016-02-01

    A soil remediation method based on magnetic beneficiation is reported. A new magnetic solid chelator powder, FS@IDA (core-shell Fe3O4@SiO2 nanoparticles coated with iminodiacetic acid chelators), was used as a reactive magnetic carrier to selectively capture non-magnetic heavy metals in soil by chelation and removal by magnetic separation. FS@IDA was prepared via inorganic-organic and organic synthesis reactions that generated chelating groups on the surface of magnetic, multi-core, core-shell Fe3O4@SiO2 (FS) nanoparticles. These reactions used a silane coupling agent and sodium chloroacetate. The results show that FS@IDA could chelate the heavy metal component of Cd, Zn, Pb, Cu and Ni carbonates, lead sulfate and lead chloride in water-insoluble salt systems. The resulting FS@IDA-Cd and FS@IDA-Pb chelates could be magnetically separated, resulting in removal rates of approximately 84.9% and 72.2% for Cd and Pb, respectively. FS@IDA could not remove the residual heavy metals and those bound to organic matter in the soil. FS@IDA did not significantly alter the chemical composition of the soil, and it allowed for fast chelating capture, simple magnetic separation and facilitated heavy metal elution. FS@IDA could also be easily prepared and reprocessed.

  13. Heavy metal ion removal by adsorption on to biological materials

    The development of regulations constraints in the industrial waste-waters management leads to the study of new treatment processes, using raw or functionalized biological materials. These processes show competitive performances in metal ion sorption efficiency for the low metal content effluents. Uptake capacities of Uranium as high as 400 mg.g-1 chitosan, equivalent to the double of the uptake capacity of fungal origin biomass, can be reached. The application of these processes to real mine wastewaters gives efficiency coefficient upper to 90%, the residual concentrations are compatible to a direct injection into the environment. The grafting of functional groups onto the chitosan scales up the sorption performances to uptake capacity upper than 600 mg.g-1 polymer. pH, metal concentration are cited as major parameters, particle size influences both uptake kinetics and sorption equilibrium, in the case of the uranium accumulation by chitosan. The desorption of uranium from the sorbent allows the valorization of uranium and the re-use of the sorbent. (authors). 21 refs., 10 figs

  14. Efficiency of lipopeptide biosurfactants in removal of petroleum hydrocarbons and heavy metals from contaminated soil.

    Singh, Anil Kumar; Cameotra, Swaranjit Singh

    2013-10-01

    This study describes the potential application of lipopeptide biosurfactants in removal of petroleum hydrocarbons and heavy metals from the soil samples collected from industrial dumping site. High concentrations of heavy metals (like iron, lead, nickel, cadmium, copper, cobalt and zinc) and petroleum hydrocarbons were present in the contaminated soil samples. Lipopeptide biosurfactant, consisting of surfactin and fengycin was obtained from Bacillus subtilis A21. Soil washing with biosurfactant solution removed significant amount of petroleum hydrocarbon (64.5 %) and metals namely cadmium (44.2 %), cobalt (35.4 %), lead (40.3 %), nickel (32.2 %), copper (26.2 %) and zinc (32.07 %). Parameters like surfactant concentration, temperature, agitation condition and pH of the washing solution influenced the pollutant removing ability of biosurfactant mixture. Biosurfactant exhibited substantial hydrocarbon solubility above its critical micelle concentration. During washing, 50 % of biosurfactant was sorbed to the soil particles decreasing effective concentration during washing process. Biosurfactant washed soil exhibited 100 % mustard seed germination contradictory to water washed soil where no germination was observed. The results indicate that the soil washing with mixture of lipopeptide biosurfactants at concentrations above its critical micelle concentration can be an efficient and environment friendly approach for removing pollutants (petroleum hydrocarbon and heavy metals) from contaminated soil. PMID:23681773

  15. Parthenium hysterophorus: Novel adsorbent for the removal of heavy metals and dyes

    S.A. Bapat

    2016-03-01

    Full Text Available Heavy metals and dyes are major contributors in contamination of water streams. These contaminants enter into our eco- system, thus posing a significant threat to public health, ecological equilibrium and environment. Thus a combined discharge of these contaminants results in water pollution with high chemical oxygen demand, biological oxygen demand, color, particulate matter, suspended particles and odor. The mounting pollution of the water bodies has attracted attention of the researchers towards the development of novel techniques and materials for water pollution. The paper describes the use of such a material Parthenium hysterophorus, a weed, explored for water purification. The potential of the weed has been tested for several heavy metals and dyes as described in this paper. As per literature the weed is capable of showing adsorption tendency up to 90% in certain cases for some heavy metals and dyes. Powdered weed, activated carbon, ash etc. of Parthenium have been employed for the removal process.

  16. Removal of heavy metals using a microbial active, continuously operated sand filter

    Heavy metals play an important role within the spectrum of the various pollutants, emitted into the environment via human activities. In contrast to most organic pollutants, heavy metal can not be degraded. Many soils, lakes and rivers show a high contamination with heavy metals due to the enrichment of these pollutants. In addition to existing chemical-physical and biological technologies for the treatment of heavy metal containing waste waters a demand for new, efficient and low-cost cleaning technologies exists, particularly for high volumes of weakly contaminated waters. Such a technology was developed within the framework of a scientific project of the European Union. The approach makes use of a continuously operated, moving-bed Astrasand filter, which has been operated as a continuous biofilm reactor. By inoculation of the reactor with bacteria providing different, defined mechanisms of metal immobilization, and by continuous supply of suitable nutrients, a metal-immobilizing biofilm is built up and regenerated continuously. Metal-enriched biomass is removed continuously from the system, and the contained metals can be recycled by pyrometallurgical treatment of the biomass. The subjects of the present work were the optimization of the nutrient supply for the process of metal removal, the investigation of the toxicity of different waste waters, the optimization of inoculation and biofilm formation, set-up and operation of a lab scale sand filter and the operation of a pilot scale sand filter treating rinsing water of a chemical nickel plating plant. First, basic parameters like toxicity of heavy metal-containing waste waters and the influence of the nutrition of bacteria on biosorption and total metal removal were examined, using freely suspended bacteria in batch culture. Concerning toxicity great differences could be found within the spectrum of heavy metal-containing waste waters tested. Some waters completely inhibited growth, while others did not

  17. Comprehensive review on phytotechnology: Heavy metals removal by diverse aquatic plants species from wastewater.

    Rezania, Shahabaldin; Taib, Shazwin Mat; Md Din, Mohd Fadhil; Dahalan, Farrah Aini; Kamyab, Hesam

    2016-11-15

    Environmental pollution specifically water pollution is alarming both in the developed and developing countries. Heavy metal contamination of water resources is a critical issue which adversely affects humans, plants and animals. Phytoremediation is a cost-effective remediation technology which able to treat heavy metal polluted sites. This environmental friendly method has been successfully implemented in constructed wetland (CWs) which is able to restore the aquatic biosystem naturally. Nowadays, many aquatic plant species are being investigated to determine their potential and effectiveness for phytoremediation application, especially high growth rate plants i.e. macrophytes. Based on the findings, phytofiltration (rhizofiltration) is the sole method which defined as heavy metals removal from water by aquatic plants. Due to specific morphology and higher growth rate, free-floating plants were more efficient to uptake heavy metals in comparison with submerged and emergent plants. In this review, the potential of wide range of aquatic plant species with main focus on four well known species (hyper-accumulators): Pistia stratiotes, Eicchornia spp., Lemna spp. and Salvinia spp. was investigated. Moreover, we discussed about the history, methods and future prospects in phytoremediation of heavy metals by aquatic plants comprehensively. PMID:27474848

  18. Removal of heavy metals in wastewater by membrane bioreactor: effects of flux and suction period

    The effects of flux and suction period on the removal of selected heavy metals including nickel, arsenic, cadmium, antimony and lead by membrane bioreactor was investigated. The sludge-age was arranged as 25 days and MLSS concentration was about 13 g/L. The flux was increased from 13 to 26 L/m2-h to understand the effects of flux on the removals. Moreover, to understand the effect of bio-film formation on the membrane plate surfaces, different samples were taken at different periods of the suction cycle. COD removal during the study was over 95%. Influent concentration of each of the heavy metals spiked directly to the wastewater was about 100 meu g/L. Effluent concentrations of cadmium and lead were under the limit of detection in all samples meaning that all the cadmium and lead were removed. Removals of over 50, 96, and 95% for arsenic, nickel and antimony were achieved, respectively. The highest removal was achieved in the first minute of the suction where the metals were accumulated in the surface biomass. (author)

  19. Heavy metals removal from aqueous environments by electrocoagulation process- a systematic review.

    Bazrafshan, Edris; Mohammadi, Leili; Ansari-Moghaddam, Alireza; Mahvi, Amir Hossein

    2015-01-01

    Heavy metals pollution has become a more serious environmental problem in the last several decades as a result releasing toxic materials into the environment. Various techniques such as physical, chemical, biological, advanced oxidation and electrochemical processes were used for the treatment of domestic, industrial and agricultural effluents. The commonly used conventional biological treatments processes are not only time consuming but also need large operational area. Accordingly, it seems that these methods are not cost-effective for effluent containing toxic elements. Advanced oxidation techniques result in high treatment cost and are generally used to obtain high purity grade water. The chemical coagulation technique is slow and generates large amount of sludge. Electrocoagulation is an electrochemical technique with many applications. This process has recently attracted attention as a potential technique for treating industrial wastewater due to its versatility and environmental compatibility. This process has been applied for the treatment of many kinds of wastewater such as landfill leachate, restaurant, carwash, slaughterhouse, textile, laundry, tannery, petroleum refinery wastewater and for removal of bacteria, arsenic, fluoride, pesticides and heavy metals from aqueous environments. The objective of the present manuscript is to review the potential of electrocoagulation process for the treatment of domestic, industrial and agricultural effluents, especially removal of heavy metals from aqueous environments. About 100 published studies (1977-2016) are reviewed in this paper. It is evident from the literature survey articles that electrocoagulation are the most frequently studied for the treatment of heavy metal wastewater. PMID:26512324

  20. Heavy metal removal by GLDA washing: Optimization, redistribution, recycling, and changes in soil fertility.

    Wang, Guiyin; Zhang, Shirong; Xu, Xiaoxun; Zhong, Qinmei; Zhang, Chuer; Jia, Yongxia; Li, Ting; Deng, Ouping; Li, Yun

    2016-11-01

    Soil washing, an emerging method for treating soils contaminated by heavy metals, requires an evaluation of its efficiency in simultaneously removing different metals, the quality of the soil following remediation, and the reusability of the recycled washing agent. In this study, we employed N,N-bis (carboxymethyl)-l-glutamic acid (GLDA), a novel and readily biodegradable chelator to remove Cd, Pb, and Zn from polluted soils. We investigated the influence of washing conditions, including GLDA concentration, pH, and contact time on their removal efficiencies. The single factor experiments showed that Cd, Pb, and Zn removal efficiencies reached 70.62, 74.45, and 34.43% in mine soil at a GLDA concentration of 75mM, a pH of 4.0, and a contact time of 60min, and in polluted farmland soil, removal efficiencies were 69.12, 78.30, and 39.50%, respectively. We then employed response surface methodology to optimize the washing parameters. The optimization process showed that the removal efficiencies were 69.50, 88.09, and 40.45% in mine soil and 71.34, 81.02, and 50.95% in polluted farmland soil for Cd, Pb, and Zn, respectively. Moreover, the overall highly effective removal of Cd and Pb was connected mainly to their highly effective removal from the water-soluble, exchangeable, and carbonate fractions. GLDA-washing eliminated the same amount of metals as EDTA-washing, while simultaneously retaining most of the soil nutrients. Removal efficiencies of recycled GLDA were no >5% lower than those of the fresh GLDA. Therefore, GLDA could potentially be used for the rehabilitation of soil contaminated by heavy metals. PMID:27371771

  1. Removal of Heavy Metal Ions from Wastewater by Using Biosorbents from Marine Algae-A Cost Effective New Technology

    2001-01-01

    Heavy metal pollution from industrial wastewater is a worldwide environmental issue. Biosorption of heavy metals by using biosorbents derived from various types of biomass has been shown to be effective for the uptake of heavy metal ions. In this study, biosorbents derived from the biomass of a group of marine macroalgae were used for the removal and recovery of heavy metal ions from aqueous solutions. Results indicated that the biosorbents have high uptake capacities and affinities for a number of heavy metal ions. The uptake capacities of the biosorbents were in the range of 1.0 to 1.5mmol·g-1 for divalent heavy metal ions. The kinetics of the uptake process was fast and the process can be used in both batch and fixed-bed operations. It appears that the biosorption process by using biosorbents from marine macroalgae can be an efficient and cost effective technology for the treatment of heavy metal containing wastewater.

  2. Chitosan membrane development and design of equipment for the removal of heavy metals from water

    A filtration technique has compared with 1,75% m/v chitosan membranes, crosslinked with glutaraldehyde (0,08% m/v) and without cross link, to quantify the removal capacity of chromium, copper and cadmium ions of model solutions. In addition, a simple and low cost equipment was developed to use with prepared membranes. The main goal has been to use biodegradable materials for removing heavy metals from water, through a low energy consumption, cheap, and applicable to specific problems. Two data sheets were prepared for the membranes and was found that chromium was the metal with the highest removal from water, by using a crosslinked membrane. Metal adsorption was best adjusted to the Freundlich isotherm model, better than Langmuir isotherm model. However, no correlation has been found between pore size of the membranes and crosslinking degree. (author)

  3. Application of Novel Nanoporous Sorbents for the Removal of Heavy Metals, Metalloids, and Radionuclides

    Mattigod, Shas V.; Fryxell, Glen E.; Parker, Kent E.; Lin, Yuehe

    2005-10-01

    A new class of hybrid nanoporous materials for removing toxic heavy metals, oxyanions, and radionuclides from aqueous waste streams has been developed at the Pacific Northwest National Laboratory. These novel materials consist of functional molecules such as thiols, ethylenediamine complexed copper, and carbamoylphosphonates that are self-assembled as monolayers within the nanopores of a synthetic silica-based material. Tests indicated that these sorbents (self-assembled monolayers on mesoporous silica ? SAMMS) can achieve very high sorbate loadings ({approx}6 meq/g) very rapidly with relatively high specificity (Kd: 1?108 ml/g). Because of the specifically tunable nature of the functionalities, these nanoporous sorbents can be targeted to remove a selected category of contaminants such as heavy metals (Ag, Cd, Cu, Hg, and Pb), oxyanions (As and Cr), and radionuclides (137Cs, 129I, 237Np, and isotopes of Pu, Th, and U) from waste streams.

  4. Characterization of natural adsorbent material for heavy metal removal in a petrochemical site contamination

    Bianchi F.

    2013-04-01

    Full Text Available Despite of over 25 years of intensive technological efforts, sub-surface environment cleanup still remains a challenge, especially in case of highly contaminated sites. In this context, ion exchanger technologies could provide simple and effective solutions for heavy metal removal in water treatment. The challenge is finding exchanger able to operate in extreme natural environments or in situations involving natural interfering species such as inorganic ions. In this paper we exam the use of natural zeolites as versatile exchanger for environmental protection of coastal refinery's groundwater against pollution of Ni, Cd, Pb. The influence of particle diameter on clinoptilolite performances toward heavy metal removal is studied. Also, we evaluate the exchanger activities in condition of high ionic strength, commonly present in groundwater located under coastal petrol industries. The obtained results confirmed that ion exchangers could provide an effective solutions for remediation in complex environmental conditions.

  5. Removal of nutrients by algae from municipal wastewater contaminated with heavy metals

    Aryal, Bigyan

    2015-01-01

    Selected species of algae (green algae and blue green algae) were cultivated in municipal wastewater using PBR (photo-bioreactor) bottles. Uptake of nutrients by these algae species was measured on different dates. From the results of the experiments, it was observed that a combination of certain blue green algae species (cyanobacteria) was able to remove most of the nutrients from the wastewater. The presence of heavy metal ions in the wastewater also affected the nutrient-absorbing capacit...

  6. Removal of heavy metals from mine wastewater using zeolite bearing tuff

    Golomeova, Mirjana; Zendelska, Afrodita; Blažev, Krsto; Krstev, Boris; Golomeov, Blagoj

    2015-01-01

    This paper presents the results of the examination of the possibility of applying zeolite bearing tuff, as a natural material, for the removal of heavy metals (copper, zinc, manganese and lead) from mine water. The experiments were performed on wastewater taken from drainage water from Svinja River above horizont XV from The mine of lead and zinc "SASA" in Makedonska Kamenica and The copper mine "Bucim" in Radovis. From the analysis can be concluded that zeolite bearing tuff...

  7. The removal of heavy metals from aqueous solution by adsorption on weathered coal

    Meena, A.K.; Gupta, M.D.; Mishra, G.K.; Rajagopal, C.; Nagar, P.N. [Central Research Institute (Ayurveda), Gwalior (India)

    2009-07-01

    The adsorption followed first-order kinetics. The results indicate the potential application of this method for effluent treatment in industries and also provide strong evidence to support the adsorption mechanism proposed. On the basis of experimental results, it can be inferred that the adsorbent weathered coal may be useful in developing an adsorptive technology for the removal of heavy metals. 25 refs., 8 figs., 4 tabs.

  8. Application of lactic acid bacteria in removing heavy metals and aflatoxin B1 from contaminated water.

    Elsanhoty, Rafaat M; Al-Turki, I A; Ramadan, Mohamed Fawzy

    2016-01-01

    In this study selected lactic acid bacteria (LAB, Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus plantrium and Streptococcus thermophiles) and probiotic bacteria (Bifidobacterium angulatum) were tested for their ability in removing heavy metals (HM) including cadmium (Cd), lead (Pb) and arsenic (As) as well as aflatoxin B1 (AFB1) from contaminated water. The biosorption parameters (pH, bacterial concentration, contact time and temperature) of removal using individual as well as mixed LAB and probiotic bacteria were studied. Removal of HM and AFB1 depended on the strain, wherein the process was strongly pH-dependent with high removal ability at a pH close to neutral. The increase in bacterial concentration enhanced the removal of Cd, Pb and As. Also, increasing of contact time and temperature increased the ability of LAB to remove HM. The effect of contact time on Cd removal was slightly different when freshly cultured cells were used. The removal of Cd, Pb and As decreased with the increase in the initial metal concentration. The most effective HM removers were Lactobacillus acidophilus and Bifidobacterium angulatum. The system was found to be adequate for concentrations of HM under investigation. At the end of the operation, the concentration of HM reached the level allowed by the World Health Organization regulations. PMID:27508367

  9. A feasibility study on bioelectrokinetics for the removal of heavy metals from tailing soil.

    Lee, Keun-Young; Kim, Hyun-A; Lee, Byung-Tae; Kim, Soon-Oh; Kwon, Young-Ho; Kim, Kyoung-Woong

    2011-01-01

    The combination of bioremediation and electrokinetics, termed bioelectrokinetics, has been studied constantly to enhance the removal of organic and inorganic contaminants from soil. The use of the bioleaching process originating from Fe- and/or S-oxidizing bacteria may be a feasible technology for the remediation of heavy metal-contaminated soils. In this study, the bioleaching process driven by injection of S-oxidizing bacteria, Acidithiobacillus thiooxidans, was evaluated as a pre-treatment step. The bioleaching process was sequentially integrated with the electrokinetic soil process, and the final removal efficiency of the combined process was compared with those of individual processes. Tailing soil, heavily contaminated with Cd, Cu, Pb, Zn, Co, and As, was collected from an abandoned mine area in Korea. The results of geochemical studies supported that this tailing soil contains the reduced forms of sulfur that can be an energy source for A. thiooxidans. From the result of the combined process, we could conclude that the bioleaching process might be a good pre-treatment step to mobilize heavy metals in tailing soil. Additionally, the electrokinetic process can be an effective technology for the removal of heavy metals from tailing soil. For the sake of generalizing the proposed bioelectrokinetic process, however, the site-specific differences in soil should be taken into account in future studies. PMID:21046430

  10. Heavy Metal Removal from Commercially-available Fruit Juice Packaged Products by Citric Acid

    Shabnam Mohammadi

    2015-03-01

    Full Text Available There has been an increasing trend in the production and consumption of local and imported fruit juices in Iran. The presence of impurities and foreign matter in finished products for human consumption is of great concern because they present health hazards when they exceed beneficial limits. The manufacture of juices requires special attention in terms of purity and the sources of water and its purification are crucial for maintaining quality and safety. Biosorption can be defined as the removal of metal or metalloid species, compounds and particulates from solution by biological material. citric acid content of beverages may be useful in nutrition therapy for calcium urolithiasis, achieving therapeutic urinary citrate concentration is one clinical target in the medical management of calcium urolithiasis. Information on the citric acid content of fruit juices and commercially-available formulations is not widely known. Levels of heavy metals: Lead, Cadmium and Nickel in 180 selected fruit juice commercially available packaged samples (Pineapple, Orange, Mango, Tropical, Cherry& Grape purchased from Tehran local Market in 2014. Heavy metals were determined using atomic absorption spectrophotometer (AAS by wet digestion method in Pharmaceutical Sciences Branch, Islamic Azad University Tehran-Iran. From the obtained result Ni, Cd and Pb were detectable in 85% of samples especially in Mango and Tropical juices. The efficiency removal of Nickel, lead and Cadmium and neutralization of calculus contain of juice by Citric acid as a chelating were carried out by using of Atomic Absorption Spectrophotometry technique. The result demonstrated the complexation formulating between the citric acid and heavy metals. The high efficiency of Citric acid played an important role in removal of lead and cadmium in addition to this removal were increased by increasing the citric acid. The enhancing of citric acid in removal of lead and cadmium caused to create a

  11. A study on removal of heavy metal ions in waste water by foam fractionation

    The purpose of this study is to remove the Cd2+, Cu2+, Hg2+, Pb2+ and Zn2+ ions in the waste water efficiently by sulfide precipitation and foam fractionation using the cationic surfactant (cetyl trimethly ammomium bromide, CTAB). In this study, the effects of pH, Na2S dose for sulfide precipitation and removal efficiency, removal rate of heavy metal ions by varying the pH range, Na2S dose and CTAB concentration were investigated. The optimum concentration of Na2S for sulfide precipitation was 1.0-1.5 equivalents to metal ions and pH range was 6.0-10.0 in coexistence of several metals. Coagulation by means of CTAB showed the best result at pH 8 and optimum CTAB concentration for foam fractionation was 40-5 mg/l at the entire pH range. Removal rate by means of form fractionation showed the following order; HgS>CdS>PbS>ZnS>CuS. Removal efficiencies of Cd2+, Cu2+, Hg2+ and Pb2+ were more than 99% at pH3-8, but Zn2+ showed more than 92% at above pH 10. When several metalions were coexisted, the optimum pH range for upmost removal efficiency showed pH 6-10 and more than 97% of them could be removed within 9 minutes.(Author)

  12. Removal of heavy metal ions from oil shale beneficiation process water by ferrite process

    Mehta, R.K.; Zhang, L.; Lamont, W.E.; Schultz, C.W. (Alabama Univ., University, AL (United States). Mineral Resources Inst.)

    1991-01-01

    The ferrite process is an established technique for removing heavy metals from waste water. Because the process water resulting from oil shale beneficiation falls into the category of industrial waste water, it is anticipated that this process may turn out to be a potential viable treatment for oil shale beneficiation process water containing many heave metal ions. The process is chemoremedial because not only effluent water comply with quality standards, but harmful heavy metals are converted into a valuable, chemically stable by-product known as ferrite. These spinel ferrites have magnetic properties, and therefore can be use in applications such as magnetic marker, ferrofluid, microwave absorbing and scavenging material. Experimental results from this process are presented along with results of treatment technique such as sulfide precipitation.

  13. Removal of heavy metal ions from oil shale beneficiation process water by ferrite process

    Mehta, R.K.; Zhang, L.; Lamont, W.E.; Schultz, C.W. [Alabama Univ., University, AL (United States). Mineral Resources Inst.

    1991-12-31

    The ferrite process is an established technique for removing heavy metals from waste water. Because the process water resulting from oil shale beneficiation falls into the category of industrial waste water, it is anticipated that this process may turn out to be a potential viable treatment for oil shale beneficiation process water containing many heave metal ions. The process is chemoremedial because not only effluent water comply with quality standards, but harmful heavy metals are converted into a valuable, chemically stable by-product known as ferrite. These spinel ferrites have magnetic properties, and therefore can be use in applications such as magnetic marker, ferrofluid, microwave absorbing and scavenging material. Experimental results from this process are presented along with results of treatment technique such as sulfide precipitation.

  14. A comparative review towards potential of microbial cells for heavy metal removal with emphasis on biosorption and bioaccumulation.

    Hansda, Arti; Kumar, Vipin; Anshumali

    2016-10-01

    The threat of heavy metal pollution to environmental health is getting worldwide attention due to their persistence and non-biodegradable nature. Ineffectiveness of various physicochemical methods due to economical and technical constraints resulted in the search for a cost-effective and eco-friendly biological technique for heavy metal removal from the environment. The two effective biotic methods used are biosorption and bioaccumulation. A comparison between these two processes demonstrated that biosorption is a better heavy metal removal process than bioaccumulation. This is due to the intoxication of heavy metal by inhibiting their entry into the microbial cell. Genes and enzymes related to bioremoval process are also discussed. On comparing the removal rate, bacteria are surpassed by algae and fungi. The aim of this review is to understand the biotic processes and to compare their metal removal efficiency. PMID:27565780

  15. Investigation of Media Effects on Removal of Heavy Metals in Bioretention Cells

    Gülbaz, Sezar; Melek Kazezyilmaz-Alhan, Cevza; Copty, Nadim K.

    2015-04-01

    Heavy metals are the most toxic elements at high concentrations, although some of them such as Cu and Zn are essential to plants, humans, and animals within a limited value. However, some heavy metals, such as Pb, have adverse effects even at low concentrations. Therefore, it is known that the toxic metals such as Zn, Cu and Pb in storm water runoff are serious threat for aquatic organisms. It is very important to control and reduce heavy metal concentration in urban storm water runoff. There are several methods to remove the aforementioned toxic metals such as electrolyte extraction, chemical precipitation, ion-exchange, reverse osmosis, membrane filtration, adsorption, cementation, and electrochemical treatment technologies. However, these methods are highly expensive and hard to implement for treatment of big volumes of water such as storm water. For this purpose, Low Impact Development (LID) Best Management Practices (BMPs) have become popular to collect, infiltrate, and treat toxic metals in storm water runoff in recent years. LID-BMP is a land planning method which is used to manage storm water runoff and improve water quality by reducing contaminant in storm water runoff. Bioretention is an example of LID-BMP application of which usage has recently been started in storm water treatment. Researchers have been investigating the advantages of bioretention systems and this study contributes to these research efforts by seeking for the media effects of bioretention on heavy metal removal. For this purpose, batch sorption experiments were performed to determine the distribution coefficients and retardation factor of copper (Cu), lead (Pb), and zinc (Zn) for bioretention media such as mulch, turf, local or vegetative soil, sand and gravel. Furthermore, sorption reaction kinetics of Cu, Pb and Zn are tested in order to assess the sorption equilibrium time of these metals for 5 bioretention media. The results of sorption test show that turf has higher sorption

  16. The removal of heavy metals from aqueous solution using natural Jordanian zeolite

    Taamneh, Yazan; Sharadqah, Suhail

    2016-02-01

    In this article, the adsorption process of cadmium and copper using natural Jordanian (NJ) zeolite as adsorbent has been experimentally estimated. The samples of NJ zeolite were obtained from Al Mafraq discrete, north east of Jordan. The influence of the bulk concentration (C o), contact time (t) and different adsorbent masses (m) of NJ zeolite on the removal of heavy metal were evaluated. These variables had a considerable function in promoting the sorption process of heavy metal using the NJ zeolite. The initial concentration of heavy metals in the stock solution was extended between 80 and 600 mg/L. The batch adsorption method was employed to investigate the adsorption process. The experimental data were correlated using Freundlich and Langmuir empirical formula. The ability of NJ zeolite to eliminate cadmium and copper was estimated according to Langmuir isotherm empirical formula and found 25.9 and 14.3 mg/g for cadmium and copper, respectively. The kinetics of adsorption of cadmium and copper have been analyzed and correlated by first-order and second-order reaction model. It was noticed that adsorption of cadmium and copper was better correlated with pseudo-second-order kinetic model. The results presented that NJ zeolite is practical adsorbent for removing cadmium and copper ion metal.

  17. Seasonal assessment, treatment and removal of heavy metal concentrations in a tropical drinking water reservoir

    Mustapha Moshood Keke

    2016-06-01

    Full Text Available Heavy metals are present in low concentrations in reservoirs, but seasonal anthropogenic activities usually elevate the concentrations to a level that could become a health hazard. The dry season concentrations of cadmium, copper, iron, lead, mercury, nickel and zinc were assessed from three sites for 12 weeks in Oyun reservoir, Offa, Nigeria. Triplicate surface water samples were collected and analysed using atomic absorption spectrophotometry. The trend in the level of concentrations in the three sites is site C > B > A, while the trend in the levels of the concentrations in the reservoir is Ni > Fe > Zn > Pb > Cd > Cu > Hg. Ni, Cd, Pb and Hg were found to be higher than the WHO guidelines for the metals in drinking water. The high concentration of these metals was from anthropogenic watershed run-off of industrial effluents, domestic sewages and agricultural materials into the reservoir coming from several human activities such as washing, bathing, fish smoking, especially in site C. The health effects of high concentration of these metals in the reservoir were highlighted. Methods for the treatment and removal of the heavy metals from the reservoir during water purification such as active carbon adsorption, coagulation-flocculation, oxidation-filtration, softening treatment and reverse osmosis process were highlighted. Other methods that could be used include phytoremediation, rhizofiltration, bisorption and bioremediation. Watershed best management practices (BMP remains the best solution to reduce the intrusion of the heavy metals from the watershed into the reservoir.

  18. Nitrogen removal and heavy metals in leachate treatment using SBR technology

    Biological nitrogen removal by the use of Sequencing Batch Reactors (SBRs) is today an accepted and well proven model. The results of SBR performance on nitrogen removal have encouraged consultants, engineering companies and landfill operators to develop and build full scale SBR plants at a number of sites in Sweden. Two of these plants, Isaetra and Norsa, have been studied closely. The Norsa plant treats leachate at a controlled water temperature, while the Isaetra plant is exposed to temperature variation throughout the year. Both plants have very well proven nitrogen removal capacities, although winter conditions have an adverse impact on their performance. Typical nitrification efficiency is close to 100%, while the total nitrogen removal is about 90-95% under stable operation conditions. A good relationship between the nitrogen load and the nitrification rate has been observed at the Norsa SBR plant. The heavy metal content in the leachate is very low thanks to anaerobic precipitation inside the landfill into metal sulphides. The heavy metal content in the biological sludge is consequently also very low.

  19. A novel biodegradable β-cyclodextrin-based hydrogel for the removal of heavy metal ions.

    Huang, Zhanhua; Wu, Qinglin; Liu, Shouxin; Liu, Tian; Zhang, Bin

    2013-09-12

    A novel biodegradable β-cyclodextrin-based gel (CAM) was prepared and applied to the removal of Cd(2+), Pb(2+) and Cu(2+) ions from aqueous solutions. CAM hydrogel has a typical three-dimensional network structure, and showed excellent capability for the removal of heavy metal ions. The effect of different experimental parameters, such as initial pH, adsorbent dosage and initial metal ion concentration, were investigated. The adsorption isotherm data fitted well to the Freundlich model. The adsorption capacity was in the order Pb(2+)>Cu(2+)>Cd(2+) under the same experimental conditions. The maximum adsorption capacities for the metal ions in terms of mg/g of dry gel were 210.6 for Pb(2+), 116.41 for Cu(2+), and 98.88 for Cd(2+). The biodegradation efficiency of the resin reached 79.4% for Gloeophyllum trabeum. The high adsorption capacity and kinetics results indicate that CAM can be used as an alternative adsorbent to remove heavy metals from aqueous solution. PMID:23911476

  20. Removal of some heavy metals by natural and synthetic materials and effect of gamma-radiation

    The adsorption of cupper, lead, cobalt and nickel from water by granular activated carbon (GAC), a strong cation exchanger (Dowex 50 w-x 8), calcium aluminum silicate and bentonite clay was studied. Batch experiments were carried out to determine the time to maintain equilibrium followed by adsorption isotherm. results obtained by using the different adsorbents were found to match with the freundlich equation. Different factors that affect the absorbability of dissolved metals were studied; among these the chemical form, solution Ph and ionic radii. The results showed that the adsorption treatment by using calcium aluminum silicate and bentonite clay resulted in more removal percent than GAC, and the strong cation exchanger. The removal of heavy metal ions from water using gamma irradiation has been investigated for the cases of Cu21, Pb21, Co21 and Ni21 ions. These metal ions are reduced by hydrated electrons and hydrogen atoms to lower valence state and eventually precipitate out of solutions

  1. Polyaza macroligands as potential agents for heavy metal removal from wastewater

    Elizondo Martínez Perla

    2013-01-01

    Full Text Available Two polyaza macroligands N,N´-bis(2-aminobenzyl-1,2- ethanediamine (L1 and 3,6,9,12-tetraaza-4(1,2,11(1,2-dibenzo-1(1,3- piridinaciclotridecafano (L2 were characterized and investigated for their metal ion extraction capabilities. The nature of all complexes was established by spectroscopic techniques. The equilibrium constants were determined by spectrophotometric and potentiometric techniques and the residual concentration of metals in the solutions by Atomic Absorption Spectrometry (AAS. The capacity of the ligands to remove heavy metals such as Cu(II, Ni(II, Cd(II, Zn(II and Pb(II as insoluble complexes was evaluated in wastewater from industrial effluents. These agents showed high affinity for the studied metals. The values of equilibrium constants of the isolated complexes (between 1 x 104 and 2 x 107 demonstrated the feasibility of applying these chelating agents as an alternative to remove heavy metals from industrial effluents.

  2. Hydrothermally modified fly ash for heavy metals and dyes removal in advanced wastewater treatment

    Visa, Maria, E-mail: maria.visa@unitbv.ro; Chelaru, Andreea-Maria, E-mail: andreea.chelaru1@yahoo.com

    2014-06-01

    Fly ash resulted from coal burning is a waste that can be used in wastewater treatment for removal of dyes and heavy metals by adsorption. Class “F” fly ash (FA), collected from the Central Heat and Power (CHP) Plant Brasov (Romania), with oxides composition SiO{sub 2}/Al{sub 2}O{sub 3} over 2.4 was used for obtaining a new substrate with good adsorption capacity for dyes and heavy metals from wastewater. A new material was obtained from modified fly ash with NaOH and hexadecyltrimethylammonium bromide (HTAB) a cationic surfactant. Contact time, optimum amount of substrate and the pH corresponding to 50 mL solution of pollutants were the parameters optimized for obtaining the maximum efficiency in the adsorption process. The optimized adsorption parameters were further used in thermodynamic and kinetic studies of the adsorption processes. The adsorption kinetic mechanisms, and the substrate capacities are further discussed correlated with the surface structure (XRD), composition (EDS, FTIR), and morphology (SEM, AFM). The results indicate that the novel nano-substrate composite with fly ash modified can be used as an efficient and low cost adsorbent for simultaneous removal of dyes and heavy metals, the resulted water respects the discharge regulations.

  3. Hydrothermally modified fly ash for heavy metals and dyes removal in advanced wastewater treatment

    Fly ash resulted from coal burning is a waste that can be used in wastewater treatment for removal of dyes and heavy metals by adsorption. Class “F” fly ash (FA), collected from the Central Heat and Power (CHP) Plant Brasov (Romania), with oxides composition SiO2/Al2O3 over 2.4 was used for obtaining a new substrate with good adsorption capacity for dyes and heavy metals from wastewater. A new material was obtained from modified fly ash with NaOH and hexadecyltrimethylammonium bromide (HTAB) a cationic surfactant. Contact time, optimum amount of substrate and the pH corresponding to 50 mL solution of pollutants were the parameters optimized for obtaining the maximum efficiency in the adsorption process. The optimized adsorption parameters were further used in thermodynamic and kinetic studies of the adsorption processes. The adsorption kinetic mechanisms, and the substrate capacities are further discussed correlated with the surface structure (XRD), composition (EDS, FTIR), and morphology (SEM, AFM). The results indicate that the novel nano-substrate composite with fly ash modified can be used as an efficient and low cost adsorbent for simultaneous removal of dyes and heavy metals, the resulted water respects the discharge regulations.

  4. Heavy metal removal from sewage sludge ash by thermochemical treatment with polyvinylchloride.

    Vogel, Christian; Exner, Robert M; Adam, Christian

    2013-01-01

    Sewage sludge ash (SSA) is a prospective phosphorus source for the future production of recycling P-fertilizers. Due to its high heavy metals contents and the relatively low P plant-availability, SSA must be treated before agricultural utilisation. In this paper SSA was thermochemically treated with PVC in a bench-scale rotary furnace in order to remove heavy metals via the chloride pathway. PVC has a high Cl-content of 52-53% and a high heating value that can be beneficially used for the thermochemical process. Large amounts of waste PVC are already recovered in recycling processes, but there are still some fractions that would be available for the proposed thermochemical process, for example, the low quality near-infrared(NIR)-fraction from waste separation facilities. Heavy metals were effectively removed at temperatures in the range of 800-950 °C via the gas phase by utilisation of PVC as Cl-donor. The resulting P plant-availability was comparable to SSA thermochemically treated with MgCl(2) as Cl-donor if MgO was used as an additive (Mg-donor). A further increase of the plant availability of phosphorus was achieved by acid post-treatment of the thermochemically treated SSA. PMID:23189972

  5. Removing heavy metals from Isfahan composting leachate by horizontal subsurface flow constructed wetland.

    Bakhshoodeh, Reza; Alavi, Nadali; Soltani Mohammadi, Amir; Ghanavati, Hossein

    2016-06-01

    Composting facility leachate usually contains high concentrations of pollutants including heavy metals that are seriously harmful to the environment and public health. The main purpose of this study was to evaluate heavy metals removal from Isfahan composting facility (ICF) leachate by a horizontal flow constructed wetland (HFCWs) system. Two horizontal systems were constructed, one planted with vetiver and the other without plant as a control. They both operated at a flow rate of 24 L/day with a 5-day hydraulic retention time (HRT). The average removal efficiencies for Cr (53 %), Cd (40 %), Ni (35 %), Pb (30 %), Zn (35 %), and Cu (40 %) in vetiver constructed wetland were significantly higher than those of the control (P < 0.05). Accumulations of heavy metals in roots were higher than shoots. Cd and Zn showed the highest and the lowest bioconcentration factor (BCF), respectively. Vetiver tolerates the extreme condition in leachate including high total dissolved solids. PMID:26983810

  6. Hydrothermally modified fly ash for heavy metals and dyes removal in advanced wastewater treatment

    Visa, Maria; Chelaru, Andreea-Maria

    2014-06-01

    Fly ash resulted from coal burning is a waste that can be used in wastewater treatment for removal of dyes and heavy metals by adsorption. Class “F” fly ash (FA), collected from the Central Heat and Power (CHP) Plant Brasov (Romania), with oxides composition SiO2/Al2O3 over 2.4 was used for obtaining a new substrate with good adsorption capacity for dyes and heavy metals from wastewater. A new material was obtained from modified fly ash with NaOH and hexadecyltrimethylammonium bromide (HTAB) a cationic surfactant. Contact time, optimum amount of substrate and the pH corresponding to 50 mL solution of pollutants were the parameters optimized for obtaining the maximum efficiency in the adsorption process. The optimized adsorption parameters were further used in thermodynamic and kinetic studies of the adsorption processes. The adsorption kinetic mechanisms, and the substrate capacities are further discussed correlated with the surface structure (XRD), composition (EDS, FTIR), and morphology (SEM, AFM). The results indicate that the novel nano-substrate composite with fly ash modified can be used as an efficient and low cost adsorbent for simultaneous removal of dyes and heavy metals, the resulted water respects the discharge regulations.

  7. Effect of pulse current on energy consumption and removal of heavy metals during electrodialytic soil remediation

    Sun, Tian Ran

    pathways to unacceptable dosages, leading to intolerable adverse effects on both public health and the environment. In the last decades, soil and water remediation have gained growing awareness, as the necessity becomes clearer for development of such techniques for elimination of the negative impact from......: transport of water (electroosmosis) and ions (electromigration), with electromigration being the most important transport process when treating heavy metal contaminated soils. Electrodialytic remediation (EDR), one of the enhanced electrochemical remediation techniques, is developed at the Technical...... applicability for remediation beyond bench and pilot scale. The overall aim of the present PhD study is to clarify and understand the underlying mechanisms of the effect of pulse current on energy consumption and removal of heavy metals during electrodialytic soil remediation. Series of experiments with...

  8. Fast removal of heavy metal ions and phytic acids from water using new modified chelating fiber

    Li Xu; Jin Nan Wang; Ying Meng; Ai Min Li

    2012-01-01

    The graft copolymerization of acrylic acid (AA) onto polyethylene glycol terephthalate (PET) fiber initiated by benzoy peroxide (BPO) was carried out in heterogeneous media.Moreover,modification of the grafted PET fiber (PET-AA) was done by changing the carboxyl group into acylamino group through the reaction with dimethylamine.The modified chelating fiber (NDWJN 1) was characterized using elementary analysis,SEM and FT-IR spectroscopy.Adsorption kinetic curves indicated that NDWJN1 could fast remove heavy metal ions and phytic acids from water effectively.Furthermore,batch kinetic studies indicated that heavy metal ions adsorbed to NDWJN1 could be fitted well by both pseudo-first-order and pseudo-second-order adsorption equations,but the intra-particle diffusion plaved a dominant role in the adsorption of phvtic acids.

  9. Adsorptive removal of heavy metals by magnetic nanoadsorbent: an equilibrium and thermodynamic study

    Shirsath, D. S.; Shirivastava, V. S.

    2015-11-01

    An efficient and new magnetic nanoadsorbent photocatalyst was fabricated by co-precipitation technique. This research focuses on understanding metal removal process and developing a cost-effective technology for treatment of heavy metal-contaminated industrial wastewater. In this investigation, magnetic nanoadsorbent has been employed for the removal of Zn(II) ions from aqueous solutions by a batch adsorption technique. The adsorption equilibrium data fitted very well to Langmuir and Freundlich adsorption isotherm models. The thermodynamics of Zn(II) ions adsorption onto the magnetic nanoadsorbents indicated that the adsorption was spontaneous, endothermic and physical in nature. Surface morphology of magnetic nanoadsorbent by scanning electron microscopy (SEM) and elemental analysis by EDX technique. The structural and photocatalytic properties of magnetic nanoadsorbent were characterized using X-ray diffraction (XRD) and FTIR techniques. Also, the magnetic properties of synthesized magnetic nanoadsorbent were determined by vibrating spinning magnetometer (VSM).

  10. Teawaste as An Adsorbent for Heavy Metal Removal from Industrial Wastewaters

    Amir H.A. Mahvi

    2005-01-01

    Full Text Available Water used in industries creates a wastewater that has a potential hazard for our environment because of introducing various contaminants such as heavy metals into soil and water resources. In this study, removal of cadmium, lead and nickel from industrial wastewaters has been investigated by using teawaste as a natural adsorbent. The research is a bench scale experimental type and analyses have performed by using different amounts of adsorbent in solutions with 5 different concentrations of each metal and also in a mixed combination. Besides, the effect of various amounts of teawaste used in adsorption efficiency experiments has been investigated. Results indicate that the removal efficiency is highest for lead and is minimum for cadmium. About 94 and 100% lead removal were achieved by using 0.5 and 1.5g adsorbent for solutions having concentrations of 5 and 10 mg/L Pb. Whereas, 1.5g teawaste can treat nickel solution of 5 mg/L concentration with an efficiency of not more that 85.7%. For cadmium, the efficiency was only 77.2% in the same conditions. On the other hand, for mixtures of metals and by applying 0.5 g teawaste, we considered a 3.5% decrease in lead removal efficiency and a 13.2% decrease in nickel adsorption for a mixed solution of 5 mg/L.

  11. Removal of Selected Heavy Metals from Green Mussel via Catalytic Oxidation

    Perna viridis or green mussel is a potentially an important aquaculture product along the South Coast of Peninsular Malaysia especially Johor Straits. As the coastal population increases at tremendous rate, there was significant effect of land use changes on marine communities especially green mussel, as the heavy metals input to the coastal area also increase because of anthropogenic activities. Heavy metals content in the green mussel exceeded the Malaysian Food Regulations (1985) and EU Food Regulations (EC No: 1881/ 2006). Sampling was done at Johor Straits from Danga to Pendas coastal area for green mussel samples. This research introduces a catalytic oxidative technique for demetallisation in green mussel using edible oxidants such as peracetic acid (PAA) enhanced with alumina beads supported CuO, Fe2O3, and ZnO catalysts. The lethal dose of LD50 to rats of PAA is 1540 mg kg-1 was verified by National Institute of Safety and Health, United State of America. The best calcination temperature for the catalysts was at 1000 degree Celsius as shown in the X-Ray Diffraction (XRD), Nitrogen Adsorption (BET surface area) and Field Emission Scanning Electron Microscopy (FESEM) analyses. The demetallisation process in green mussel was done successfully using only 100 mgL-1 PAA and catalyzed with Fe2O3/ Al2O3 for up to 90 % mercury (Hg) removal. Using PAA with only 1 hour of reaction time, at room temperature (30-35 degree Celsius), pH 5-6 and salinity of 25-28 ppt, 90 % lead (Pb) was removed from life mussel without catalyst. These findings have a great prospect for developing an efficient and practical method for post-harvesting heavy metals removal in green mussel. (author)

  12. Effective heavy metal removal from aqueous systems by thiol functionalized magnetic mesoporous silica

    A thiol-functionalized magnetic mesoporous silica material (called SH-mSi-Fe3O4), synthesized by a modified Stoeber method, has been investigated as a convenient and effective adsorbent for heavy metal ions. Structural characterization by powder X-ray diffraction, N2 adsorption-desorption isotherm, Fourier transform infrared spectroscopy and elemental analyses confirms the mesoporous structure and the organic moiety content of this adsorbent. The high saturation magnetization (38.4 emu/g) make it easier and faster to be separated from water under a moderate magnetic field. Adsorption kinetics was elucidated by pseudo-second-order kinetic equation and exhibited 3-stage intraparticle diffusion mode. Adsorption isotherms of Hg and Pb fitted well with Langmuir model, exhibiting high adsorption capacity of 260 and 91.5 mg of metal/g of adsorbent, respectively. The distribution coefficients of the tested metal ions between SH-mSi-Fe3O4 and different natural water sources (groundwater, lake water, tap water and river water) were above the level of 105 mL/g. The material was very stable in different water matrices, even in strong acid and alkaline solutions. Metal-loaded SH-mSi-Fe3O4 was able to regenerate in acid solution under ultrasonication. This novel SH-mSi-Fe3O4 is suitable for repeated use in heavy metal removal from different water matrices.

  13. Microbiological treatment for removal of heavy metals and nutrients in FGD wastewater

    Shulder, Stephen J. [Structural Integrity Associates, Annapolis, MD (United States); Riffe, Michael R. [Siemens Water Technologies, General Industry Solutions, Warrendale, PA (United States); Walp, Richard J. [URS Corporation, Princeton, NJ (United States)

    2010-12-15

    In efforts to comply with the Clean Air Act many coal-fired fossil plants are installing wet flue gas desulfurization (WFGD) systems, also known as scrubbers, to remove sulfur dioxide (SO{sub 2}). Limestone slurry is injected into an absorber to promote the formation of calcium sulfate (CaSO{sub 4}) or gypsum. Chloride (chlorine in the fuel) becomes dissolved and increases in the absorber loop, which can lead to a more corrosive environment. Inert matter in the limestone also enters the absorber and must be reduced to meet the gypsum quality specification. To control the buildup of chloride and fines in the flue gas desulfurization (FGD) system a continuous blowdown or purge stream is utilized. Environmental regulations on the discharge of treated FGD wastewater are becoming increasingly more stringent to control impacts on the receiving body of water (stream, lake, river, or ocean). These new limitations often focus on heavy metals such as selenium and nutrients including nitrogen and phosphorus compounds. The FGD chloride purge stream is typically treated by chemical addition and clarification to remove excess calcium and heavy metals with pH adjustment prior to discharge. However this process is not efficient at selenium or nutrient removal. Information on a new approach using biological reactor systems or sequencing batch reactors (SBRs) to achieve reductions in selenium and nitrogen compounds (ammonia, nitrite, and nitrate) is discussed. A brief discussion on the physical/chemical pretreatment is also provided. (orig.)

  14. Removal mechanisms of heavy metal pollution from urban runoff in wetlands

    Zhang, Zhiming; Cui, Baoshan; Fan, Xiaoyun

    2012-12-01

    Solid particles, particularly urban surface dust in urban environments contain large quantities of pollutants. It is considered that urban surface dust is a major pollution source of urban stormwater runoff. The stormwater runoff washes away urban surface dust and dissolves pollutants adsorbed onto the dust and finally discharges into receiving water bodies. The quality of receiving water bodies can be deteriorated by the dust and pollutants in it. Polluted waters can be purified by wetlands with various physical, chemical, and biologic processes. These processes have been employed to treat pollutants in urban stormwater runoff for many years because purification of treatment wetlands is a natural process and a low-cost method. In this paper, we reviewed the processes involved during pollutants transport in urban environments. Particularly, when the urban stormwater runoff enters into wetlands, their removal mechanisms involving various physical, chemical and biologic processes should been understood. Wetlands can remove heavy metals by absorbing and binding them and make them form a part of sediment. However, heavy metals can be released into water when the conditions changed. This information is important for the use of wetlands for removing of pollutants and reusing stormwater.

  15. Removal mechanisms of heavy metal pollution from urban runoff in wetlands

    Zhiming ZHANG; Baoshan CUI; Xiaoyun FAN

    2012-01-01

    Solid particles,particularly urban surface dust in urban environments contain large quantities of pollutants.It is considered that urban surface dust is a major pollution source of urban stormwater runoff.The stormwater runoffwashes away urban surface dust and dissolves pollutants adsorbed onto the dust and finally discharges into receiving water bodies.The quality of receiving water bodies can be deteriorated by the dust and pollutants in it.Polluted waters can be purified by wetlands with various physical,chemical,and biologic processes.These processes have been employed to treat pollutants in urban stormwater runoff for many years because purification of treatment wetlands is a natural process and a low-cost method.In this paper,we reviewed the processes involved during pollutants transport in urban environments.Particularly,when the urban stormwater runoff enters into wetlands,their removal mechanisms involving various physical,chemical and biologic processes should been understood.Wetlands can remove heavy metals by absorbing and binding them and make them form a part of sediment.However,heavy metals can be released into water when the conditions changed.This information is important for the use of wetlands for removing of pollutants and reusing stormwater.

  16. Heavy-metal removal from petroleum oily sludge using lemon- scented geraniums[General Conference

    Badawieh, A.; Elektorowicz, M. [Concordia Univ., Montreal, PQ (Canada). Dept. of Building, Civil and Environmental Engineering

    2006-07-01

    Finding an acceptable method to manage oily sludge generated during petroleum processes is one of the challenges currently facing the petroleum industry. This study investigated the response of plants to heavy-metal removal from oily sludge to determine the feasibility of using phytoremediation technologies as a treatment method for oily sludge. In particular, scented geraniums (Pelargonium sp. Frensham) have shown a strong capability to survive harsh conditions such as poor soil, high/low temperatures, high heavy-metal concentrations and low water content. In response to this observation, this feasibility study placed scented geraniums in a series of pots containing oily sludge where heavy-metal concentrations were artificially increased up to 2000 ppm. Plants were grown in two systems over a period of 50 days. The first system included oily sludge and soil while the second system included oily sludge, soil and compost. The study revealed that the scented geraniums accumulated up to 1600 mg, 1000 mg, and 1200 mg, of cadmium, nickel and vanadium respectively per 1 kg of the plant's dry weight. The results suggest that phytoremediation technology may be a potential method for successfully treating or pretreating oily sludge in the field.

  17. UV-radiation curing of simultaneous interpenetrating polymer network hydrogels for enhanced heavy metal ion removal

    Wang, Jingjing, E-mail: jjwang1@hotmail.com [Department of Polymer Materials and Engineering, School of Material Engineering, Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province, Yancheng Institute of Technology, Yancheng 224051 (China); Liu, Fang [Department of Polymer Materials and Engineering, School of Material Engineering, Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province, Yancheng Institute of Technology, Yancheng 224051 (China)

    2012-11-01

    Highlights: Black-Right-Pointing-Pointer Simultaneous IPN hydrogels were prepared by hybrid photopolymerization of AM and DVE-3. Black-Right-Pointing-Pointer The synergistic complexation was found in the adsorption studies. Black-Right-Pointing-Pointer The simultaneous IPN hydrogels could be used as fast-responsive and renewable sorbent materials. - Abstract: Simultaneous interpenetrating polymer network (IPN) hydrogels have been prepared by UV-initiated polymerization of a mixture of acrylamide (AM) and triethylene glycol divinyl ether (DVE-3). The consumption of each monomer upon UV-irradiation was monitored in situ by real-time infrared (RTIR) spectroscopy. The acrylamide monomer AM was shown to polymerize faster and more extensively than the vinyl ether monomer DVE-3, which was further consumed upon storage of the sample in the dark, due to the living character of the cationic polymerization. The IPN hydrogels were used to remove heavy metal ions from aqueous solution under the non-competitive condition. The effects of pH values of the feed solution and the DVE-3 content in the formulation on the adsorption capacity were investigated. The results indicated that the adsorption capacity of the IPN hydrogels increased with the pH values and DVE-3 content in the formulation. Furthermore, the synergistic complexation of metal ions with two polymer networks in the IPN was found in the adsorption studies. Adsorption kinetics and regeneration studies suggested that the IPN hydrogels could be used as fast-responsive and renewable sorbent materials in heavy metal removing processes.

  18. Separation of heavy metals: Removal from industrial wastewaters and contaminated soil

    Peters, R.W.; Shem, L.

    1993-03-01

    This paper reviews the applicable separation technologies relating to removal of heavy metals from solution and from soils in order to present the state-of-the-art in the field. Each technology is briefly described and typical operating conditions and technology performance are presented. Technologies described include chemical precipitation (including hydroxide, carbonate, or sulfide reagents), coagulation/flocculation, ion exchange, solvent extraction, extraction with chelating agents, complexation, electrochemical operation, cementation, membrane operations, evaporation, adsorption, solidification/stabilization, and vitrification. Several case histories are described, with a focus on waste reduction techniques and remediation of lead-contaminated soils. The paper concludes with a short discussion of important research needs in the field.

  19. Separation of heavy metals: Removal from industrial wastewaters and contaminated soil

    Peters, R.W.; Shem, L.

    1993-01-01

    This paper reviews the applicable separation technologies relating to removal of heavy metals from solution and from soils in order to present the state-of-the-art in the field. Each technology is briefly described and typical operating conditions and technology performance are presented. Technologies described include chemical precipitation (including hydroxide, carbonate, or sulfide reagents), coagulation/flocculation, ion exchange, solvent extraction, extraction with chelating agents, complexation, electrochemical operation, cementation, membrane operations, evaporation, adsorption, solidification/stabilization, and vitrification. Several case histories are described, with a focus on waste reduction techniques and remediation of lead-contaminated soils. The paper concludes with a short discussion of important research needs in the field.

  20. Chelating capture and magnetic removal of non-magnetic heavy metal substances from soil

    Liren Fan; Jiqing Song; Wenbo Bai; Shengping Wang; Ming Zeng; Xiaoming Li; Yang Zhou; Haifeng Li; Haiwei Lu

    2016-01-01

    A soil remediation method based on magnetic beneficiation is reported. A new magnetic solid chelator powder, FS@IDA (core-shell Fe3O4@SiO2 nanoparticles coated with iminodiacetic acid chelators), was used as a reactive magnetic carrier to selectively capture non-magnetic heavy metals in soil by chelation and removal by magnetic separation. FS@IDA was prepared via inorganic-organic and organic synthesis reactions that generated chelating groups on the surface of magnetic, multi-core, core-shel...

  1. Removal of heavy metals from aqueous solution using Rhizopus delemar mycelia in free and polyurethane-bound form

    This study assesses the ability of mycelia of Rhizopus delemar (both free and immobilized on polyurethane foam) to remove heavy metals from single-ion solutions as well as from a mixture of them. All experiments were conducted using 0.5-5 mM solutions of CuSO4.5H2O, CoCl2.6H2O and FeSO4.7H2O. Mycelia immobilized on polyurethane foam cells showed some times increase in uptake compared with that of free cells. Metal ions accumulation from a mixed solution was decreased slightly for cobalt and iron and considerable for copper ions. Heavy metal uptake was examined in the immobilized column experiments and more than 92% heavy metal removal (mg heavy metals removed/mg heavy metals added) from a mixed solution was achieved during the 5 cycles. During these experiments, the dry weight of the immobilized cells was decreased by only 2%. These results showed that immobilized mycelia of Rhizopus delemar can be used repeatedly for removal of heavy metals from aqueous solutions. (orig.)

  2. The application of fish scales in removing heavy metals from energy-produced waste streams: the role of microbes

    Mustafiz, S. [Dalhousie University, halifax, Nova Scotia (Canada). Faculty of Engineering

    2003-09-01

    In energy production, heavy metals pose significant contamination hazards. For example, the petroleum industry generates wastes that are often high in heavy metal concentrations. Heavy metals are very toxic and extremely deleterious to humans, plants, and animals. Application of fish scale to remove heavy metals is a very recent innovation. It is an environmentally appealing and economically attractive alternative to current heavy metal adsorbing materials. Previously, the adsorption phenomenon on this exotic waste material was explained by only physical-chemical reactions. Biological effects on adsorption of heavy metals such as lead, arsenic, and chromium were studied using Atlantic Cod scale. The difference in results between nonsterilized and sterilized experiments shows the microbial contribution to heavy metal removal. Results show a wide range of microbial contribution in removing chromium cations. For lead and arsenic cations, the effect is less. Measurement of pH gives some indication of the microbial role in the biosorption process and of the presence of possible microbial species. (author)

  3. The application of fish scales in removing heavy metals from energy-produced waste streams: the role of microbes

    In energy production, heavy metals pose significant contamination hazards. For example, the petroleum industry generates wastes that are often high in heavy metal concentrations. Heavy metals are very toxic and extremely deleterious to humans, plants, and animals. Application of fish scale to remove heavy metals is a very recent innovation. It is an environmentally appealing and economically attractive alternative to current heavy metal adsorbing materials. Previously, the adsorption phenomenon on this exotic waste material was explained by only physical-chemical reactions. Biological effects on adsorption of heavy metals such as lead, arsenic, and chromium were studied using Atlantic Cod scale. The difference in results between nonsterilized and sterilized experiments shows the microbial contribution to heavy metal removal. Results show a wide range of microbial contribution in removing chromium cations. For lead and arsenic cations, the effect is less. Measurement of pH gives some indication of the microbial role in the biosorption process and of the presence of possible microbial species. (author)

  4. Poly(ethylene glycol dimethacrylate-n-vinyl imidazole) beads for heavy metal removal

    Poly(ethylene glycol dimethacrylate-n-vinyl imidazole) [poly(EGDMA-VIM)] hydrogel (average diameter 150-200 μm) was prepared by copolymerizing ethylene glycol dimethacrylate (EGDMA) with n-vinyl imidazole (VIM). The copolymer hydrogel bead composition was characterized by elemental analysis and found to contain 5 EGDMA monomer units each VIM monomer unit. Poly(EGDMA-VIM) beads had a specific surface area of 59.8 m2/g. Poly(EGDMA-VIM) beads were characterized by swelling studies and scanning electron microscopy (SEM). These poly(EGDMA-VIM) beads with a swelling ratio of 78% were used for the heavy metal removal studies. Chelation capacity of the beads for the selected metal ions, i.e., Cd(II), Hg(II) and Pb(II) were investigated in aqueous media containing different amounts of these ions (10-750 mg/l) and at different pH values (3.0-7.0). Chelation rate was very fast. The maximum chelation capacities of the poly(EGDMA-VIM) beads were 69.4 mg/g for Cd(II), 114.8 mg/g for Pb(II) and 163.5 mg/g for Hg(II). The affinity order on molar basis was observed as follows: Hg(II)>Cd(II)>Pb(II). Chelation behavior of heavy metal ions could be modelled using both the Langmuir and Freundlich isotherms. pH significantly affected the chelation capacity of VIM incorporated beads. Chelation of heavy metal ions from synthetic wastewater was also studied. The chelation capacities are 45.6 mg/g for Cd(II), 74.2 mg/g for Hg(II) and 92.5 mg/g for Pb(II) at 0.5 mmol/l initial metal concentration. Regeneration of the chelating-beads was easily performed with 0.1 M HNO3. These features make poly(EGDMA-VIM) beads potential candidate adsorbent for heavy metal removal

  5. Comparative evaluation of microbial and chemical leaching processes for heavy metal removal from dewatered metal plating sludge

    Bayat, Belgin, E-mail: bbayat@cu.edu.tr [Department of Environmental Engineering, Faculty of Engineering and Architecture, Cukurova University, Balcali, Adana 01330 (Turkey); Sari, Bulent [Department of Environmental Engineering, Faculty of Engineering and Architecture, Cukurova University, Balcali, Adana 01330 (Turkey)

    2010-02-15

    The purpose of the study described in this paper was to evaluate the application of bioleaching technique involving Acidithiobacillus ferrooxidans to recover heavy metals (Zn, Cu, Ni, Pb, Cd and Cr) in dewatered metal plating sludge (with no sulfide or sulfate compounds). The effect of some conditional parameters (i.e. pH, oxidation-reduction potential (ORP), sulfate production) and operational parameters (i.e. pulp density of the sludge and agitation time) were investigated in a 3 l completely mixed batch (CMB) reactor. The metal recovery yields in bioleaching were also compared with chemical leaching of the sludge waste using commercial inorganic acids (sulfuric acids and ferric chloride). The leaching of heavy metals increased with decreasing of pH and increasing of ORP and sulfate production during the bioleaching experiment. Optimum pulp density for bioleaching was observed at 2% (w/v), and leaching efficiency decreased with increasing pulp density in bioleaching experiments. Maximum metal solubilization (97% of Zn, 96% of Cu, 93% of Ni, 84% of Pb, 67% of Cd and 34% of Cr) was achieved at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 {+-} 2 deg. C during the bioleaching process. The maximum removal efficiencies of 72% and 79% Zn, 70% and 75% Cu, 69% and 73% Ni, 57% and 70% Pb, 55% and 65% Cd, and 11% and 22% Cr were also attained with the chemical leaching using sulfuric acids and ferric chloride, respectively, at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 {+-} 2 deg. C during the acid leaching processes. The rates of metal leaching for bioleaching and chemical leaching are well described by a kinetic equation related to time. Although bioleaching generally requires a longer period of operation compared to chemical leaching, it achieves higher removal efficiency for heavy metals. The efficiency of leaching processes can be arranged in descending order as follows: bioleaching > ferric chloride leaching > sulfuric

  6. Comparative evaluation of microbial and chemical leaching processes for heavy metal removal from dewatered metal plating sludge

    The purpose of the study described in this paper was to evaluate the application of bioleaching technique involving Acidithiobacillus ferrooxidans to recover heavy metals (Zn, Cu, Ni, Pb, Cd and Cr) in dewatered metal plating sludge (with no sulfide or sulfate compounds). The effect of some conditional parameters (i.e. pH, oxidation-reduction potential (ORP), sulfate production) and operational parameters (i.e. pulp density of the sludge and agitation time) were investigated in a 3 l completely mixed batch (CMB) reactor. The metal recovery yields in bioleaching were also compared with chemical leaching of the sludge waste using commercial inorganic acids (sulfuric acids and ferric chloride). The leaching of heavy metals increased with decreasing of pH and increasing of ORP and sulfate production during the bioleaching experiment. Optimum pulp density for bioleaching was observed at 2% (w/v), and leaching efficiency decreased with increasing pulp density in bioleaching experiments. Maximum metal solubilization (97% of Zn, 96% of Cu, 93% of Ni, 84% of Pb, 67% of Cd and 34% of Cr) was achieved at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 ± 2 deg. C during the bioleaching process. The maximum removal efficiencies of 72% and 79% Zn, 70% and 75% Cu, 69% and 73% Ni, 57% and 70% Pb, 55% and 65% Cd, and 11% and 22% Cr were also attained with the chemical leaching using sulfuric acids and ferric chloride, respectively, at pH 2, solids contents of 2% (w/v), and a reaction temperature of 25 ± 2 deg. C during the acid leaching processes. The rates of metal leaching for bioleaching and chemical leaching are well described by a kinetic equation related to time. Although bioleaching generally requires a longer period of operation compared to chemical leaching, it achieves higher removal efficiency for heavy metals. The efficiency of leaching processes can be arranged in descending order as follows: bioleaching > ferric chloride leaching > sulfuric acid

  7. Magnetite–hematite nanoparticles prepared by green methods for heavy metal ions removal from water

    Graphical abstract: The negatively charged cubic magnetite nanoparticles, prepared by the coprecipitation method in N2 atmosphere, can adsorb up to 99% of the positively charged toxic heavy metal ions at a proper pH value. -- Highlights: • Mixed magnetite–hematite nanoparticles were synthesized via different routes. • Prepared samples were characterized by XRD, HRTEM, BET and magnetic hysteresis. • The material was employed as a sorbent for removal of some heavy metal ions from water. • The effects of pH and the contact time on the adsorption process were studied and optimized. -- Abstract: Mixed magnetite–hematite nanoparticles were synthesized via different routes such as, coprecipitation in air and N2 atmosphere, citrate–nitrate, glycine–nitrate and microwave-assisted citrate methods. The prepared samples were characterized by X-ray diffraction (XRD), high resolution transmission electron microscope (HRTEM), BET measurements and magnetic hysteresis. XRD data showed the formation of magnetite–hematite mixture with different compositions according to the synthesis method. The particle size was in the range of 4–52 nm for all the prepared samples. From HRTEM micrographs, it was found that, the synthesis method affects the moropholgy of the prepared samples in terms of crystallinity and porosity. The magnetite–hematite mixture was employed as a sorbent material for removal of some heavy metal ions from water such as lead(II), cadmium(II) and chromium(III). The effects of pH value and the contact time on the adsorption process were studied and optimized in order to obtain the highest possible adsorption efficiency of the magnetite–hematite mixture. The effect of the synthesis method of the magnetite–hematite mixture on the adsorption process was also investigated. It was found that samples prepared by the coprecipitation method had better adsorption efficiency than those prepared by other combustion methods

  8. The mechanisms of removal of heavy metals from water by ionizing radiation

    The removal of heavy metal ions from water using electron beam and gamma irradiation has been investigated for the cases of Pb2+ and Hg2+ ions. These metal ions are reduced by hydrated electrons and hydrogen atoms to lower or zero valence state and eventually precipitate out of solution. Ethanol is applied as a relatively non-toxic additive to scavenge ·OH radicals, to enhance reduction and inhibit oxidation. Mercury can be completely (>99.9%) removed from aqueous solution of 1x10-3 mol L-1 mercury (II) chloride by using a 3 kGy dose. However, a 40 kGy dose is required to remove 96% of lead ions from a 1x10-3 mol L-1 of PbCl2 solution. The effect of dissolved oxygen and carbonate were also investigated. E-beam irradiation of 1x10-3 mol L-1 lead ions complexed with ethylenediamine tetraacetic acid (EDTA) in deoxygenated as well as air-saturated solutions in the absence of ethanol resulted in removal of about 97% of the lead

  9. Synthesis of Mesoporous Adsorbent and its Application for Heavy Metal Ions Removal from Aqueous Solution

    The mesoporous silicas were synthesized via the evaporation-induced self-assembly (EISA) in the experiment. Cetyltrimethyl ammonium bromide (CTAB) was used as the template, and the silicon source was tetraethoxyorthosilicate (TEOS). The mesoporous silicas were characterized by nitrogen adsorption-desorption analysis, FTIR, TEM and SEM. The mesoporous silicas (adsorbent) exhibited higher pore diameter (centered at 5.57 nm), BET surface area (457.3 m2·g-1) and pore volume (0.563 cm2·g-1). The mesoporous silicas were used as the adsorbent to remove the heavy metal ions from aqueous solution. The following order of equilibrium adsorption capacity for Cu2+, Co2+, Ag+ and As3+ on adsorbent was: Ag+>Cu2+>Co2+>As3+. Analysis of adsorption kinetics showed that Cu2+, Co2+, Ag+ and As3+ adsorption fit the pseudo-second-order nonlinear model significantly. The removal rate for heavy metal ions was high, and the adsorbent can be regenerated by acid treatment without altering its properties.

  10. Influence of vegetation on the removal of heavy metals and nutrients in a constructed wetland.

    Maine, M A; Suñe, N; Hadad, H; Sánchez, G; Bonetto, C

    2009-01-01

    A free water surface wetland was built to treat wastewater containing metals (Cr, Ni, Zn) and nutrients from a tool factory in Argentina. Water, sediment and macrophytes were sampled in the inlet and outlet area of the constructed wetland during three years. Three successive phases of vegetation dominance were developed and three different patterns of contaminant retention were observed. During the Eichhornia crassipes dominance, contaminants were retained in the macrophyte biomass; during the E. crassipes+Typha domingensis stage, contaminants were retained in the sediment and in the T. domingensis dominance stage, contaminants were retained in sediment and in the macrophyte biomass. Removal efficiency was not significantly different among the three vegetation stages, except for NH(4)(+) and i-P(diss). Because of its highest tolerance, T. domingensis is the best choice to treat wastewater of high pH and conductivity with heavy metals, a common result from many industrial processes. PMID:18079048

  11. Optimization of heavy metal and suspended solids removal using groundwater treatment plant sludge (GWTPS)

    Full text: A groundwater treatment plant located in Chicha, Kelantan, produced 5 tons of sludge daily that require offsite disposal. The sludge was found to contain high concentration of iron and manganese. An attempt was made to reuse the Groundwater Treatment Plant Sludge (GWTPS) for wastewater treatment purposes. This study is focusing on the effectiveness of GWTPS as an adsorbent in removing Zn and Cu, as well as coagulant in removing suspended solids. The characteristic of the freshly prepared GWTPS was analyzed by measuring its pH in distilled water and total Fe concentration. Adsorption study was conducted using GWTPS. Using batch test method, parameters such as pH, contact time, adsorbent dosage and initial concentration of sorbent was varied in order to find the optimum in removing Zn and Cu. The ability of GWTPS in removing Zn and Cu was further analyzed based on its removal efficiency. Recycled Ferric Chloride (RFC) and Recycled Ferrous Sulphate (RFS) are generated from GWTPS through a digestion process using Environmental Express Hot Block. The optimization of RFC and RFS was determined by varying the GWTPS dosage and contact time during digestion. Both RFC and RFS was tested for its efficiency as a coagulant in removing Zn, Cu and suspended solids by jar test method. It was found that GWTPS was effective in removing Zn and Cu. From the study it can be concluded that RFC and RFS, a coagulant derived from groundwater sludge, is effective in removing suspended solids that contain heavy metals such as Zn and Cu. (author)

  12. Remediation of heavy metal polluted sediment by suspension and solid-bed leaching: estimate of metal removal efficiency.

    Löser, Christian; Zehnsdorf, Andreas; Hoffmann, Petra; Seidel, Heinz

    2007-01-01

    Remediation of heavy metal polluted sediment by extracting the metals with sulfuric acid can be performed as follows: abiotic suspension leaching, microbial suspension leaching, abiotic solid-bed leaching, and microbial solid-bed leaching. Abiotic leaching means that the acid is directly added, while microbial leaching means that the acid is generated from sulfur by microbes (bioleaching). These four principles were compared to each other with special emphasis on the effectiveness of metal solubilization and metal removal by subsequent washing. Abiotic suspension leaching was fastest, but suspending the solids exhibits some disadvantages (low solid content, costly reactors, permanent input of energy, high water consumption, special equipment required for solid separation, large amounts of waste water, sediment properties hinder reuse), which prevent suspension leaching in practice. Abiotic solid-bed leaching implies the supply of acid by percolating water which proceeds slowly due to a limited bed permeability. Microbial solid-bed leaching means the generation of acid within the bed and has been proven to be the only principle applicable to practice. Metal removal from leached sediment requires washing with water. Washing of solid beds was much more effective than washing of suspended sediment. The kinetics of metal removal from solid beds 0.3, 0.6 or 1.2m in height were similar; when using a percolation flow of 20lm(-2)h(-1), the removal of 98% of the mobile metals lasted 57-61h and required 8.5, 4.2 or 2.3lkg(-1) water. This means, the higher the solid bed, the lower the sediment-mass-specific demand for time and water. PMID:16908047

  13. BIOSORPTIVE REMOVAL OF HEAVY METALS (Cd+2, Pb+2 AND Cu+2 FROM AQUEOUS SOLUTIONS BY CASSIA ANGUSTIFOLIA BARK

    MADHAVI G MULGUND,

    2011-02-01

    Full Text Available The hazardous ill effects of heavy metals on the environment and public health is a matter of serious concern. Biosorption is emerging as a sustainable effective technology. The aim of this present study was to investigate the removal of heavy metals (Cd+2, Pb+2 and Cu+2 using Cassia angustifolia bark. The objective was to evaluate the biosorbent for its metal uptake and study its batch equilibrium. The batch mode was carried out at varying initial pH (5 to 9, emperature (300C to 450C, metal ion concentration (20mg to 140mg/L and contact time (5 min to 240 min and desorption studies from pH 1 to 11. The equilibrium data obtained fit well in Langmuir and Freundlich isotherms. The results of the investigations show the efficacy of Cassia angustifolia bark as a low cost promising biosorbent for removal of heavy metals from industrial wastewaters.

  14. The Predisposition of Iraqi Rice Husk to Remove Heavy Metals from Aqueous Solutions and Capitalized from Waste Residue

    Mohammed Nsaif

    2013-12-01

    Full Text Available This study is deal with study the potential of Iraqi Rice Husk (IRH on the removal of three heavy metals pollutant which were (Mg, Mn and Mo ions from industrial wastewater using different design parameters by adsorption process. Results show that the removal efficiency were (93.95, 97.18 and 95.26 % for heavy metal (Mg, Mn and Mo respectively from aquatic solution decreased with increasing of initial concentration and flow rate while the removal efficiency increased with increasing absorbance material bed height, pH and feeding temperature. Statistical model is achieved to find an expression relates the overall operating parameters with the removal efficiency for each metal ions used in this investigation in a general equation (each one alone. The samples of (IRH remaining after using it in the removal of (Mg, Mn and Mo heavy metal ions above from Simulated Synthetic Aqueous Solutions (SSAS to investigate the capitalized of it in different methods. Different benefits possess which are: remove the three toxic heavy metals ions contaminated the water, get rid of agricultural waste (IRH, in the same time, produce light and more benefit hydrocarbons from n-heptane isomerization using a type Y-zeolite catalyst synthesis from remaining (IRH and prepare a cheap and active rodenticide.

  15. Simultaneous removal of organic contaminants and heavy metals from kaolin using an upward electrokinetic soil remediation process.

    Wang, Jing-Yuan; Huang, Xiang-Jun; Kao, Jimmy C M; Stabnikova, Olena

    2007-06-01

    Kaolins contaminated with heavy metals, Cu and Pb, and organic compounds, p-xylene and phenanthrene, were treated with an upward electrokinetic soil remediation (UESR) process. The effects of current density, cathode chamber flushing fluid, treatment duration, reactor size, and the type of contaminants under the vertical non-uniform electric field of UESR on the simultaneous removal of the heavy metals and organic contaminants were studied. The removal efficiencies of p-xylene and phenanthrene were higher in the experiments with cells of smaller diameter or larger height, and with distilled water flow in the cathode chamber. The removal efficiency of Cu and Pb were higher in the experiments with smaller diameter or shorter height cells and 0.01M HNO(3) solution as cathode chamber flow. In spite of different conditions for removal of heavy metals and organics, it is possible to use the upward electrokinetic soil remediation process for their simultaneous removal. Thus, in the experiments with duration of 6 days removal efficiencies of phenanthrene, p-xylene, Cu and Pb were 67%, 93%, 62% and 35%, respectively. The experiment demonstrated the feasibility of simultaneous removal of organic contaminants and heavy metals from kaolin using the upward electrokinetic soil remediation process. PMID:17110023

  16. Organic substrates as electron donors in permeable reactive barriers for removal of heavy metals from acid mine drainage.

    Kijjanapanich, P; Pakdeerattanamint, K; Lens, P N L; Annachhatre, A P

    2012-12-01

    This research was conducted to select suitable natural organic substrates as potential carbon sources for use as electron donors for biological sulphate reduction in a permeable reactive barrier (PRB). A number of organic substrates were assessed through batch and continuous column experiments under anaerobic conditions with acid mine drainage (AMD) obtained from an abandoned lignite coal mine. To keep the heavy metal concentration at a constant level, the AMD was supplemented with heavy metals whenever necessary. Under anaerobic conditions, sulphate-reducing bacteria (SRB) converted sulphate into sulphide using the organic substrates as electron donors. The sulphide that was generated precipitated heavy metals as metal sulphides. Organic substrates, which yielded the highest sulphate reduction in batch tests, were selected for continuous column experiments which lasted over 200 days. A mixture of pig-farm wastewater treatment sludge, rice husk and coconut husk chips yielded the best heavy metal (Fe, Cu, Zn and Mn) removal efficiencies of over 90%. PMID:23437664

  17. Removal and treatment of radioactive, organochlorine, and heavy metal contaminants from solid surfaces

    The U.S. Department of Energy (DOE) is defining decontamination and decommissioning (D ampersand D) obligations at its sites. Current D ampersand D activities are generally labor intensive, use chemical reagents that are difficult to treat, and may expose workers to radioactive and hazardous chemicals. Therefore, new technologies are desired that minimize waste, allow much of the decommissioned materials to be reused rather than disposed of as waste, and produce wastes that will meet disposal criteria. The O'Brien ampersand Gere companies tested a scouring decontamination system on concrete and steel surfaces contaminated with radioactive and hazardous wastes under the sponsorship of Martin Marietta Energy Systems, Inc. (MMES) at DOE's K-25 former gaseous diffusion plant in Oak Ridge, Tennessee. The scouring system removes fixed radioactive and hazardous contamination yet leaves the surface intact. Blasting residuals are treated using physical/chemical processes. Bench- and pilot-scale testing of the system was conducted on surfaces contaminated with uranium, technetium, heavy metals, and PCBs. Areas of concrete and metal surfaces were blasted. Residuals were dissolved in tap water and treated for radioactive, hazardous, and organochlorine constituents. The treatment system comprised pH adjustment, aeration, solids settling, filtration, carbon adsorption, and ion exchange. This system produced treated water and residual solid waste. Testing demonstrated that the system is capable of removing greater than 95% of radioactive and PCB surface contamination to below DOE's unrestricted use release limits; aqueous radionuclides, heavy metals, and PCBs were below DOE and USEPA treatment objectives after treatment. Waste residuals volume was decreased by 71 %. Preliminary analyses suggest that this system provides significant waste volume reduction and is more economical than alternative surface decontamination techniques that are commercially available or under development

  18. Removal and treatment of radioactive, organochlorine and heavy metal contaminants from solid surfaces

    The U.S. Department of Energy (DOE) is defining decontamination and decommissioning (D ampersand D) obligations at its sites. Current D ampersand D activities are Generally labor intensive, use chemical reagents that are difficult to treat, and may expose workers to radioactive and hazardous chemicals. Therefore, new technologies are desired that minimize waste, allow much of the decommissioned materials to be reused rather than disposed of as waste, and produce wastes that will meet disposal criteria The O'Brien ampersand Gere Companies tested a scouring decontamination system on concrete and steel surfaces contaminated with radioactive and hazardous wastes under the sponsorship of Martin Marietta Energy Systems, Inc. (MMES) at DOE's K-25 former gaseous diffusion plant in Oak Ridge, Tennessee. The scouring system that O'Brien ampersand Gere Companies developed removes fixed radioactive and hazardous surface contamination, while leaving the surface intact. Blasting residuals are dissolved and treated using physical/chemical processes. Bench- and pilot-scale testing of the soda blasting system was conducted between December 1993 and September 1994 on surfaces contaminated with uranium, technetium, heavy metals, and PCBs. Areas of concrete and metal surfaces were blasted. Blasting residuals were dissolved in tap water and treated for radioactive, hazardous, and organochlorine constituents. The treatment system comprised pH adjustment, aeration, solids settling, filtration, carbon adsorption, and ion exchange. This system produced treated water and residual solid waste. Testing demonstrated that the system is capable of removing greater than 95% of radioactive and PCB surface contamination to below DOE's unrestricted use release limits; aqueous radionuclides, heavy metals, and PCBs were below DOE and USEPA treatment objectives after blasting residuals treatment. Waste residuals volume was decreased by 71%

  19. Chemical studies on the preparation of magnetic nanoparticles coated with glycine and its application for removal of heavy metals

    Jawaher Alzaidi

    2016-06-01

    Full Text Available The aim of this study is the preparation of magnetic nanoparticles and coating with glycine to remove heavy metals such as Cu+2. The magnetic nanoparticles were prepared by co-precipitation method using using ferrous sulphate and potassium nitrate in presence of potassium hydroxide. Different instrumental analysis such as XRD, TEM, SEM and EDAX were used to study the magnetic nanoparticles which produced and comparing it after coated with glycine. The optimum conditions which reflect the high efficiency of removal are pH 10, concentration of the heavy metal 200 ppm, dosage 0.05 g and for 24 h duration time. Therefore we recommend using magnetic nanoparticles coated with glycine for removal of heavy metals.

  20. A study of the removal characteristics of heavy metals from wastewater by low-cost adsorbents

    Omar E. Abdel Salam

    2011-10-01

    Full Text Available In this study, the adsorption behavior of some low-cost adsorbents such as peanut husk charcoal, fly ash, and natural zeolite, with respect to Cu2+, and Zn2+ ions, has been studied in order to consider its application to the purification of metal finishing wastewater. The batch method was employed: parameters such as pH, contact time, and initial metal concentration were studied. The influence of the pH of the metal ion solutions on the uptake levels of the metal ions by the different adsorbents used were carried out between pH 4 and pH 11. The optimum pH for copper and zinc removal was 6 in the case of peanut husk charcoal and natural zeolite, and it was 8 in case of fly ash. An equilibrium time of 2 h was required for the adsorption of Cu(II and Zn(II ions onto peanut husk charcoal and fly ash and an equilibrium time 3 h was required for the adsorption of Cu(II and Zn(II ions onto natural zeolite. Adsorption parameters were determined using both Langmuir and Freundlich isotherms, but the experimental data were better fitted to the Langmuir equation than to Freundlich equation. The results showed that peanut husk charcoal, fly ash and natural zeolite all hold potential to remove cationic heavy metal species from industrial wastewater in the order fly ash < peanut husk charcoal < natural zeolite.

  1. Evaluation of the capability of low-impact development practices for the removal of heavy metal from urban stormwater runoff.

    Maniquiz-Redillas, Marla C; Kim, Lee-Hyung

    2016-09-01

    Low-impact development (LID) and green infrastructure (GI) have recently become well-known methods to capture, collect, retain, and remove pollutants in stormwater runoff. The research was conducted to assess the efficiency of LID/GI systems applied in removing the particulate and dissolved heavy metals (Zn, Pb, Cu, Ni, Cr, Cd, and Fe) from urban stormwater runoff. A total of 82 storm events were monitored over a four-year period (2010-2014) on six LID/GI systems including infiltration trenches, tree box filter, rain garden, and hybrid constructed wetlands employed for the management of road, parking lot, and roof runoff. It was observed that the heavy metal concentration increased proportionally with the total suspended solids concentration. Among the heavy metal constituents, Fe appeared to be highly particulate-bound and was the easiest to remove followed by Zn and Pb; while metals such as Cr, Ni, Cu, and Cd were mostly dissolved and more difficult to remove. The mass fraction ratios of metal constituents at the effluent were increased relative to the influent. All the systems performed well in the removal of particulate-bound metals and were more efficient for larger storms greater than 15 mm wherein more particulate-bound metals were generated compared to smaller storms less than 5 mm that produced more dissolved metals. The efficiency of the systems in removing the particulate-bound metals was restricted during high average/peak flows; that is, high-intensity storms events and when heavy metals have low concentration levels. PMID:26862669

  2. Removal of heavy metals from aqueous solution by adsorption on biomass based adsorbent

    Alam, Sultan; Azmatullah, M. [Malakand Univ., Chakdara, Dir (Pakistan). Dept. of Chemistry; Bangash, Fazlullah Khan [Peshawar Univ. (Pakistan). Inst. of Chemical Sciences; Amin, Noor-ul [Abdul Wali Khan Univ., Mardan (Pakistan). Dept. of Chemistry

    2013-09-15

    Removal of heavy metals i.e. Zn{sup 2+} and Cd{sup 2+} from aqueous solution by adsorption onto biomass based adsorbent was investigated as a function of time and different concentrations. The sample was characterized by FTIR, EDS, BET surface area and Zeta potential technique, which was reported earlier. Adsorption kinetics of Zn{sup 2+} and Cd{sup 2+} was tested by first order kinetics, 'Elovich and parabolic diffusion kinetic equations which show that the process of adsorption is diffusion controlled process. The rate of adsorption was high at high adsorption temperature. Thermodynamic parameters like {Delta}H , {Delta}S and {Delta}G were calculated from the kinetic data. The negative value of Gibbs free energy ({Delta}G ) shows the spontaneous nature of the process. Freundlich, Langmuir, Temkin isotherms and distribution coefficient were found fit to the adsorption isotherm data. (orig.)

  3. Construction of Inorganic and Hybrid Biosorbents for Heavy Metal Ions Removal

    Lyudmila Kabaivanova

    2015-12-01

    Full Text Available Hybrid biosorbents, synthesized by the sol-gel method on the basis of Tetraethylorthosilicate (TEOS proved to be efficient for the removal of the heavy metal ions from aqueous solutions. The potential use of immobilized in TEOS algal cells of the red microalga Porphyridium cruentum and its products - low and high molecular heteropolysaccharides to remove Cu(II, Cd(II and Ni(II ions was evaluated. A laboratory bioreactor was involved in this process. Sol-gel sorbent with TEOS only was used as a control system to the hybrid biosorbents. Their structural characterization was performed using different methods. The maximum adsorption capacities were registered for the biosorbents with immobilized algal biomass and for the preparations with TEOS and high molecular algal heteropolysaccharide: for Cu(II, Cd(II and Ni(II, they were 18.771 and 21.715 mg·Cd·g-1 adsorbent; 16.662 and 17.545 mg·Ni/g-1 adsorbent and 40.633 and 34.431 mg·Cu·g-1 adsorbent, respectively. The adsorption of toxic Cu(II, Zn(II and Ni(II ions in the four types of sorbents proved to be effective. High percent of these ions removal was obtained during the first hours of the adsorption process.

  4. Contemplating the feasibility of vermiculate blended chitosan for heavy metal removal from simulated industrial wastewater

    Prakash, N.; Soundarrajan, M.; Arungalai Vendan, S.; Sudha, P. N.; Renganathan, N. G.

    2015-12-01

    Wastewater contaminated by heavy metals pose great challenges as they are non biodegradable, toxic and carcinogenic to the soil and aquifers. Vermiculite blended with chitosan have been used to remove Cr(VI) and Cd(II) from the industrial wastewater. The results indicate that the vermiculite blended with chitosan adsorb Cr(VI) and Cd(II) from industrial waste water. Batch adsorption experiments were performed as a function of pH 5.0 and 5.5 respectively for chromium and cadmium. The adsorption rate was observed to be 72 and 71 % of chromium and cadmium respectively. The initial optimum contact time for Cr(VI) was 300 min with 59.2 % adsorption and 300 min for Cd(II) with 71.5 % adsorption. Whereas, at 4-6 there is saturation, increasing the solid to liquid ratio for chitosan biopolymers increases the number of active sites available for adsorption. The optimum pH required for maximum adsorption was found to be 5.0 and 5.5 for chromium and cadmium respectively. The experimental equilibrium adsorption data were fitted using Langmuir and Freundlich equations. It was observed that adsorption kinetics of both the metal ions on vermiculite blended chitosan is well be analyzed with pseudo-second-order model. The negative free energy change of adsorption indicates that the process was spontaneous and vermiculite blended chitosan was a favourable adsorbent for both the metals.

  5. Removal turbidity and separation of heavy metals using electrocoagulation-electroflotation technique

    The electrocoagulation (EC) process was developed to overcome the drawbacks of conventional wastewater treatment technologies. This process is very effective in removing organic pollutants including dyestuff wastewater and allows for the reduction of sludge generation. The purposes of this study were to investigate the effects of the operating parameters, such as pH, initial concentration (C0), duration of treatment (t), current density (j), interelectrode distance (d) and conductivity (κ) on a synthetic wastewater in the batch electrocoagulation-electroflotation (EF) process. The optimal operating conditions were determined and applied to a textile wastewater and separation of some heavy metals. Initially a batch-type EC-EF reactor was operated at various current densities (11.55, 18.6, 35.94, 56.64, 74.07 and 91.5 mA/cm2) and various interelectrode distance (1, 2 and 3 cm). For solutions with 300 mg/L of silica gel, high turbidity removal (89.54%) was obtained without any coagulants when the current density was 11.55 mA/cm2, initial pH was 7.6, conductivity was 2.1 mS/cm, duration of treatment was 10 min and interelectrode distance was 1 cm. The application of the optimal operating parameters on a textile wastewater showed a high removal efficiency for various items: suspended solid (SS) 86.5%, turbidity 81.56%, biological oxygen demand (BOD5) 83%, chemical oxygen demand (COD) 68%, and color over 92.5%. During the EC process under these conditions, we have studied the separation of some heavy metal ions such as iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), lead (Pb) and cadmium (Cd) with different initial concentrations in the range of 50-600 mg/L and initial pH between 7.5 and 7.8. This allowed us to show that the kinetics of electrocoagulation-electroflotation is very quick (<15 min), and the removal rate reaches 95%

  6. Removal turbidity and separation of heavy metals using electrocoagulation-electroflotation technique

    Merzouk, B. [Departement d' Hydraulique, Universite Mohamed Boudiaf de M' sila (Algeria)], E-mail: mbelkov@yahoo.fr; Gourich, B. [Laboratoire de Genie des Procedes, Ecole Superieure de Technologie de Casablanca, B.P. 8012, Oasis (Morocco); Sekki, A. [Departement de Genie des Procedes, Universite Ferhat Abbas de Setif (Algeria); Madani, K.; Chibane, M. [Faculte des Sciences de la Nature et de la Vie, Universite A - Mira de Bejaia (Algeria)

    2009-05-15

    The electrocoagulation (EC) process was developed to overcome the drawbacks of conventional wastewater treatment technologies. This process is very effective in removing organic pollutants including dyestuff wastewater and allows for the reduction of sludge generation. The purposes of this study were to investigate the effects of the operating parameters, such as pH, initial concentration (C{sub 0}), duration of treatment (t), current density (j), interelectrode distance (d) and conductivity ({kappa}) on a synthetic wastewater in the batch electrocoagulation-electroflotation (EF) process. The optimal operating conditions were determined and applied to a textile wastewater and separation of some heavy metals. Initially a batch-type EC-EF reactor was operated at various current densities (11.55, 18.6, 35.94, 56.64, 74.07 and 91.5 mA/cm{sup 2}) and various interelectrode distance (1, 2 and 3 cm). For solutions with 300 mg/L of silica gel, high turbidity removal (89.54%) was obtained without any coagulants when the current density was 11.55 mA/cm{sup 2}, initial pH was 7.6, conductivity was 2.1 mS/cm, duration of treatment was 10 min and interelectrode distance was 1 cm. The application of the optimal operating parameters on a textile wastewater showed a high removal efficiency for various items: suspended solid (SS) 86.5%, turbidity 81.56%, biological oxygen demand (BOD{sub 5}) 83%, chemical oxygen demand (COD) 68%, and color over 92.5%. During the EC process under these conditions, we have studied the separation of some heavy metal ions such as iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), lead (Pb) and cadmium (Cd) with different initial concentrations in the range of 50-600 mg/L and initial pH between 7.5 and 7.8. This allowed us to show that the kinetics of electrocoagulation-electroflotation is very quick (<15 min), and the removal rate reaches 95%.

  7. Comparative Study for Removal of Some Heavy Metals from Liquid Wastes Using Natural Resources and Bacteria

    Twenty three bacterial strains have been isolated from polluted water and soil samples of Ismailia Canal in Egypt. The polluted sites were at Abu Zabal Factory (fertilizer factory), Elshaba factory (Aluminum sulfate factory) and Oil-pipes Company (petrochemical materials). By screening the abilities of these isolates to tolerate heavy metals, it has been found that isolate MAM-4was the most potent isolate. This isolate was identified as Providencia rettgeri. As the concentration of Al3+ increased the ability of P. rettgeri to uptake Al3+ decreased. P. rettgeri could remove 97.2% of Al3+ from 25 mg/L. Bacillus cereus ATCC 11778 (American Type Culture Collection, U.S.A) gave the same trend for Al3+ uptake but P. rettgeri was more tolerant to Al3+ than B. cereus ATCC 11778.With increasing Co2+ concentration, abilities of P. rettgeri and B. cereus ATCC 11778 to uptake decreased. P. rettgeri could uptake 59 mg/L Co2+ from 200 mg/L (29.5%), while B. cereus ATCC 11778 uptake 68.3 mg/L (34.1%). Also, as the concentration of Cu2+ increased the abilities of P. rettgeri and B. cereus ATCC 11778 to uptake Cu2+ decreased. P. rettgeri removed 11.5 mg/Cu2+ from 25 mg/L (47.0%), while B. cereus ATCC 11778 removed 13.5 mg/L from the some concentration (54.%). Combined treatment of 1.0% untreated clay with P. rettgeri could remove 471.8 mg/L Al3+ from 500 mg/L (94.4%), 82.4 mg/L Co2+ from 200 mg/L (41.2%) and 150 mg/L Cu2+ from 300 mg/L (50%). However, 1.0 % treated clay combined with P. rettgeri adsorbed 207.8 mg/L Al3+from 500 mg/L (41.5%), 52.0 mg/L Co2+ from 200 mg/L (26.0%) and 185 mg/L Cu2+ from 300 mg/L (61.6%). The combined treatment adsorbed more heavy metals than clay only or bacterial cells only. Three KGy gamma radiations reduced the viable count of P. rettgeri by 7.4 log cycles. P. rettegri mutant MI was able to tolerate more Al3+ than the parent strain

  8. Kinetic study of heavy metal ions removal from aqueous solutions using activated pumice stone

    Naseh Babakhani

    2016-05-01

    Full Text Available Background: The presence of heavy metals in aquatic and terrestrial ecosystems causes harmful effects to living organisms in the environment. This research aimed to determine the potential of activated pumice stone (APS as a sorbent for the removal of Cd, Cu, and Zn from wastewater. Methods: This research was conducted during 2013 on a laboratory scale. The study was performed using batch experiments with synthetic wastewater having Cd, Cu, and Zn concentrations of 10, 20, 40, and 80 mg/L. Various isotherm models, including Langmuir and Freundlich, were used to evaluate the sorption data. The influence of contact time and amount of sorbent on the removal of Cd, Cu, and Zn from wastewater was studied. All experiments were done at pH = 7 and at room temperature (20 ± 1°C. The solution pH was adjusted using 1N NaOH or 1N HCl solutions, and the pH value was determined by a pH meter. Results: The results showed that the adsorption of Cd, Cu, and Zn approaches equilibrium after about 2 hours, while the rates of removal efficiency for Cd, Cu, and Zn at equilibrium were 91.6%, 91.8%, and 82.9%, respectively. Kinetic studies showed that the sorption of Cd, Cu, and Zn onto APS were fitted to the pseudo-second order kinetic models. Conclusion: The results indicate that the APS is a good choice, because it is a low-cost and effective sorbent. The sorption capacity of APS as a sorbent was considerably affected by the initial concentration of metal ions in the solution and by contact time.

  9. Effective removal of heavy metals from industrial sludge with the aid of a biodegradable chelating ligand GLDA

    Highlights: • A novel readily biodegradable chelating ligand was employed to remove heavy metals. • The effects of different conditions on the extraction with GLDA were probed. • Species distribution of metals before and after extraction with GLDA was analyzed. • GLDA was effective for Cd extraction from sludge samples under various conditions. • GLDA offers special insights in the effective removal of heavy metals. - Abstract: Tetrasodium of N,N-bis(carboxymethyl) glutamic acid (GLDA), a novel readily biodegradable chelating ligand, was employed for the first time to remove heavy metals from industrial sludge generated from a local battery company. The extraction of cadmium, nickel, copper, and zinc from battery sludge with the presence of GLDA was studied under different experimental conditions such as contact times, pH values, as well as GLDA concentrations. Species distribution of metals in the sludge sample before and after extraction with GLDA was also analyzed. Current investigation showed that (i) GLDA was effective for Cd extraction from sludge samples under various conditions. (ii) About 89% cadmium, 82% nickel and 84% copper content could be effectively extracted at the molar ratio of GLDA:M(II) = 3:1 and at pH = 4, whereas the removal efficiency of zinc was quite low throughout the experiment. (iii) A variety of parameters, such as contact time, pH values, the concentration of chelating agent, stability constant, as well as species distribution of metals could affect the chelating properties of GLDA

  10. Rapid Preparation of Biosorbents with High Ion Exchange Capacity from Rice Straw and Bagasse for Removal of Heavy Metals

    Supitcha Rungrodnimitchai

    2014-01-01

    Full Text Available This work describes the preparation of the cellulose phosphate with high ion exchange capacity from rice straw and bagasse for removal of heavy metals. In this study, rice straw and bagasse were modified by the reaction with phosphoric acid in the presence of urea. The introduced phosphoric group is an ion exchangeable site for heavy metal ions. The reaction by microwave heating yielded modified rice straw and modified bagasse with greater ion exchange capacities (∼3.62 meq/g and shorter reaction time (1.5–5.0 min than the phosphorylation by oil bath heating. Adsorption experiments towards Pb2+, Cd2+, and Cr3+ ions of the modified rice straw and the modified bagasse were performed at room temperature (heavy metal concentration 40 ppm, adsorbent 2.0 g/L. The kinetics of adsorption agreed with the pseudo-second-order model. It was shown that the modified rice straw and the modified bagasse could adsorb heavy metal ions faster than the commercial ion exchange resin (Dowax. As a result of Pb2+ sorption test, the modified rice straw (RH-NaOH 450W removed Pb2+ much faster in the initial step and reached 92% removal after 20 min, while Dowax (commercial ion exchange resin took 90 min for the same removal efficiency.

  11. Influence of the civil construction debris layer in heavy metals removal of the leachate submitted to recirculation in landfill

    Maike Rossmann

    2010-08-01

    Full Text Available Little is known about the ability of stabilized organic matter (old MSW and construction waste (RCC to retain heavy metals from leachate generated in landfills. The objective of this study was to assess the potential of MSW to remove old heavy metals in MSW leachate produced by freshly collected, and the effect of RCC in the concentration of heavy metals in effluents from MSW old. In three columns (CR, put a layer of RCC and then MSW old and, on the other three (SR, only MSW old. Analyzed in the leachate and effluent pH, EC, BOD and metals Zn, Cd, Cu and Pb. There were similar and efficient removal of BOD and heavy metals in both treatments. The presence of the layer of RCC was considered important to the overall improvement in effluent quality, but did not influence the concentration of metals in the effluent. The order of retention of metals in the columns was: Cu ~ Pb> Cd> Zn. With the exception of Cd and Zn, all other variables assessed in the effluent were below the maximum standards set in DN 01.08 COPAM / CERH for release effluent into water bodies.

  12. Removal of Heavy Metal Ions with Acid Activated Carbons Derived from Oil Palm and Coconut Shells

    Mokhlesur M. Rahman

    2014-05-01

    Full Text Available In this work, batch adsorption experiments were carried out to investigate the suitability of prepared acid activated carbons in removing heavy metal ions such as nickel(II, lead(II and chromium(VI. Acid activated carbons were obtained from oil palm and coconut shells using phosphoric acid under similar activation process while the differences lie either in impregnation condition or in both pretreatment and impregnation conditions. Prepared activated carbons were modified by dispersing hydrated iron oxide. The adsorption equilibrium data for nickel(II and lead(II were obtained from adsorption by the prepared and commercial activated carbons. Langmuir and Freundlich models fit the data well. Prepared activated carbons showed higher adsorption capacity for nickel(II and lead(II. The removal of chromium(VI was studied by the prepared acid activated, modified and commercial activated carbons at different pH. The isotherms studies reveal that the prepared activated carbon performs better in low concentration region while the commercial ones in the high concentration region. Thus, a complete adsorption is expected in low concentration by the prepared activated carbon. The kinetics data for Ni(II, Pb(II and Cr(VI by the best selected activated carbon fitted very well to the pseudo-second-order kinetic model.

  13. Synthesis and Characterization of Iron Oxide Nanoparticles and Applications in the Removal of Heavy Metals from Industrial Wastewater

    Zuolian Cheng; Annie Lai Kuan Tan; Yong Tao; Dan Shan; Kok Eng Ting; Xi Jiang Yin

    2012-01-01

    This study investigated the applicability of maghemite (γ-Fe2O3) nanoparticles for the selective removal of toxic heavy metals from electroplating wastewater. The maghemite nanoparticles of 60 nm were synthesized using a coprecipitation method and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDX). Batch experiments were carried out for the removal of Pb2+ ions from aqueous solutions by maghemite nanoparticl...

  14. Pumice Characteristics and Their Utilization on the Synthesis of Mesoporous Minerals and on the Removal of Heavy Metals

    Ismail, A. I. M.; El-Shafey, O. I.; Amr, M. H. A.; El-Maghraby, M. S.

    2014-01-01

    Wastewater treatment of some heavy metals was carried out by synthetic zeolite P1, which was prepared by alkaline hydrothermal treatment of the pumice. Both of the pumice raw materials and synthetic zeolite were investigated for their chemical phase composition, physical properties, and microstructure. The adsorption behavior of Na-zeolite P1 with respect to Co+2, Cu+2, Fe+2, and Cd+2 has been studied to be applied in the industrial wastewater treatment. Metal removal was investigated using s...

  15. Efficiency of Algae Combinations in heavy metal removal from waste-waters using photo-bio-reactor

    Bello, Adedayo

    2015-01-01

    The aim of this thesis was to compare the efficiency of different algal combinations in heavy metals removal from wastewater using algae-based photo-bioreactors. Twelve different strains of algae were divided into four groups and were introduced into twenty-four photo-bioreactor bottles: twelve contained wastewaters only while the other twelve contained wastewaters con-taminated with 90 mg of heavy metal. Parameters such as temperature, pH, light and conductivi-ty, which are believed to affec...

  16. Electrodialytic removal of heavy metals from municipal solid waste incineration fly ash using ammonium citrate as assisting agent

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Villumsen, Arne

    2005-01-01

    Electrodialytic remediation, an electrochemically assisted separation method, has previ-ously shown potential for removal of heavy metals from municipal solid waste incineration (MSWI) fly ashes. In this work electrodialytic remediation of MSWI fly ash using ammonium citrate as assisting agent was...... studied, and the results were compared with traditional batch extraction experiments. The application of electric current was found to increase the heavy metal release significantly compared to batch extraction experiments at comparable conditions (same liquid-to-solid ratio, same assisting agent, and...

  17. In vitro removal of toxic heavy metals by poly(γ-glutamic acid-coated superparamagnetic nanoparticles

    Inbaraj BS

    2012-08-01

    Full Text Available Baskaran Stephen Inbaraj,1 Bing-Huei Chen1,21Department of Food Science, 2Graduate Institute of Medicine, Fu Jen University, Taipei, TaiwanBackground: Chelation therapy involving organic chelators for treatment of heavy metal intoxication can cause cardiac arrest, kidney overload, mineral deficiency, and anemia.Methods: In this study, superparamagnetic iron oxide nanoparticles (SPIONs modified with an edible biopolymer poly(γ-glutamic acid (PGA were synthesized by coprecipitation method, characterized and evaluated for their removal efficiency of heavy metals from a metal solution, and simulated gastrointestinal fluid (SGIF.Results: Instrumental characterization of bare- and PGA-SPIONs revealed 7% coating of PGA on SPIONs with a spherical shape and an iron oxide spinel structure belonging to magnetite. The particle sizes as determined from transmission electron microscopy images were 8.5 and 11.7 nm for bare- and PGA-SPIONs, respectively, while the magnetization values were 70.3 and 61.5 emu/g. Upon coating with PGA, the zeta potentials were shifted from positive to negative at most of the environmental pH (3–8 and biological pH (1–8, implying good dispersion in aqueous suspension and favorable conditions for heavy metal removal. Batch studies showed rapid removal of lead and cadmium with the kinetic rates estimated by pseudo-second-order model being 0.212 and 0.424 g/mg•min, respectively. A maximum removal occurred in the pH range 4–8 in deionized water and 5–8 in SGIF corresponding to most gastrointestinal pH except for the stomach. Addition of different ionic strengths (0.001–1 M sodium acetate and essential metals (Cu, Fe, Zn, Mg, Ca, and K did not show any marked influence on lead removal by PGA-SPIONs, but significantly reduced the binding of cadmium. Compared to deionized water, the lead removal from SGIF was high at all pH with the Langmuir monolayer removal capacity being 98.70 mg/g for the former and 147.71 mg/g for the

  18. Mechanism study of selective heavy metal ion removal with polypyrrole-functionalized polyacrylonitrile nanofiber mats

    Wang, Jianqiang; Luo, Chao [Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China); Qi, Genggeng [Department of Materials Science and Engineering, Cornell University, Ithaca, NY (United States); Pan, Kai, E-mail: pankai@mail.buct.edu.cn [Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China); Department of Materials Science and Engineering, Cornell University, Ithaca, NY (United States); Cao, Bing, E-mail: bcao@mail.buct.edu.cn [Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China)

    2014-10-15

    Graphical abstract: - Highlights: • PAN/PPy core/shell nanofiber used for Cr(VI) removal. • Adsorption mechanisms were investigated. • Selective adsorption performances were investigated. - Abstract: Polyacrylonitrile/polypyrrole (PAN/PPy) core/shell nanofiber mat was prepared through electrospinning followed by a simple chemical oxidation method. The polypyrrole-functionalized nanofiber mats showed selective adsorption performance for anions. The interaction between heavy metal anions and polypyrrole (especially the interaction between Cr{sub 2}O{sub 7}{sup 2−} and polypyrrole) during the adsorption process was studied. The results showed that the adsorption process included two steps: one was the anion exchange process between the Cl{sup −} and Cr(VI), and the other was the redox process for the Cr(VI) ions. The adsorption amount was related to the protonation time of the PAN/PPy nanofiber mat and increased as protonation time increased. Meanwhile, the Cr(VI) ions were reduced to Cr(III) through the reaction with amino groups of polypyrrole (from secondary amines to tertiary amines). PAN/PPy nanofiber mat showed high selectivity for Cr(VI), and the adsorption performance was nearly unaffected by other co-existing anions (Cl{sup −}, NO{sub 3}{sup −}, and SO{sub 4}{sup 2−}) except for PO{sub 4}{sup 3−} for the pH change.

  19. Mechanism study of selective heavy metal ion removal with polypyrrole-functionalized polyacrylonitrile nanofiber mats

    Graphical abstract: - Highlights: • PAN/PPy core/shell nanofiber used for Cr(VI) removal. • Adsorption mechanisms were investigated. • Selective adsorption performances were investigated. - Abstract: Polyacrylonitrile/polypyrrole (PAN/PPy) core/shell nanofiber mat was prepared through electrospinning followed by a simple chemical oxidation method. The polypyrrole-functionalized nanofiber mats showed selective adsorption performance for anions. The interaction between heavy metal anions and polypyrrole (especially the interaction between Cr2O72− and polypyrrole) during the adsorption process was studied. The results showed that the adsorption process included two steps: one was the anion exchange process between the Cl− and Cr(VI), and the other was the redox process for the Cr(VI) ions. The adsorption amount was related to the protonation time of the PAN/PPy nanofiber mat and increased as protonation time increased. Meanwhile, the Cr(VI) ions were reduced to Cr(III) through the reaction with amino groups of polypyrrole (from secondary amines to tertiary amines). PAN/PPy nanofiber mat showed high selectivity for Cr(VI), and the adsorption performance was nearly unaffected by other co-existing anions (Cl−, NO3−, and SO42−) except for PO43− for the pH change

  20. The Use of Microwave Derived Activated Carbon for Removal of Heavy Metal in Aqueous Solution

    Rafeah Wahi

    2011-09-01

    Full Text Available Palm oil processing waste which is palm oil kernel shell (POKS was converted to activated carbon (POKS AC through 7 min microwave pyrolysis at temperature 270 °C followed by chemical activation using NaOH and HCl. The adsorption study on Ni(II, Cu(II and Cr(IV was conducted to evaluate the efficiency of the prepared activated carbon to remove heavy metal. The adsorption capacity was determined as a function of adsorbate initial concentration and adsorbent dosage. Based on Langmuir isotherm, Ni(II showed highest adsorption capacity of 40.98 mg/g, followed by Cr(IV and Cu(II with adsorption capacity of 40.60 mg/g and 13.69 mg/g, respectively. Cr(IV and Cu(II showed better fitting to Freundlich isotherm model with high correlation regression indicating the applicability of heterogeneous adsorption. Ni(II show better fitting with Langmuir isotherm that indicate monolayer coverage. The use of POKS AC is not only effective for adsorption of Cr(IV, Ni(II and Cu(II in aqueous solution but also helps to overcome the over abundance of POKS waste problem.

  1. Removal of heavy metals from a contaminated soil using tartaric acid

    KE Xin; LI Pei-jun; ZHOU Qi-xing; ZHANG Yun; SUN Tie-heng

    2006-01-01

    This study reports the feasibility of remediation of a heavy metal (HM) contaminated soil using tartaric acid, an environmentally-friendly extractant. Batch experiments were performed to test the factors influencing remediation of the HM contaminated soil. An empirical model was employed to describe the kinetics of HM dissolution/desorption and to predict equilibrium concentrations of HMs in soil leachate. The changes of HMs in different fractions before and after tartaric acid treatment were also investigated. Tartaric acid solution containing HMs was regenerated by chestnut shells. Results show that utilization of tartaric acid was effective for removal of HMs from the contaminated soil, attaining 50%-60% of Cd, 40%-50% of Pb, 40%-50% of Cu and 20%-30% of Zn in the pH range of 3.5-4.0 within 24 h. Mass transfer coefficients for cadmium (Cd) and lead (Pb) were much higher than those for copper (Cu) and zinc (Zn). Sequential fractionations of treated and untreated soil samples showed that tartaric acid was effective in removing the exchangeable, carbonate fractions of Cd, Zn and Cu from the contaminated soil. The contents of Pb and Cu in Fe-Mn oxide fraciton were also significantly decreased by tartaric acid treatment. One hundred milliliters of tartaric acid solution containing HMs could be regenerated by 10 g chestnut shells in a batch reactor. Such a remediation procedure indicated that tartaric acid is a promising agent for remediation of HM contaminated soils. However, further research is needed before the method can be practically used for in situ remediation of contaminated sites.

  2. Linen Fire as Biosorbent to Remove Heavy Metal Ions From Wastewater Modeling

    Ildar G. Shaikhiev

    2014-03-01

    Full Text Available The possibility of using linen fires – lnopererabotk i waste as a sorption material for the extraction of heavy metal ions from wastewater modeling. It is shown that treatment with acid solutions linen fires a low concentration increases the surface area of linen fires and thus sorption capacity for heavy metal ions. The values of the maximum sorption capacity ions Fe (III, Co (II, Ni (II and Zn (II under static and dynamic conditions. IR spectroscopy shows that along with the physical sorption process proceeds chemisorption.

  3. Characterization and application of dried plants to remove heavy metals, nitrate, and phosphate ions from industrial wastewaters

    Chiban, Mohamed; Soudani, Amina; Sinan, Fouad [Department of Chemistry, Faculty of Sciences, Agadir (Morocco); Tahrouch, Saida [Department of Biology, Faculty of Sciences, Agadir (Morocco); Persin, Michel [European Membrane Institute, CRNS, Montpellier (France)

    2011-04-15

    Low cost adsorbents were prepared from dried plants for the removal of heavy metals, nitrate, and phosphate ions from industrial wastewaters. The efficiency of these adsorbents was investigated using batch adsorption technique at room temperature. The dried plant particles were characterized by N{sub 2} at 77 K adsorption, scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and phytochemical screening. The adsorption experiments showed that the microparticles of the dried plants presented a good adsorption of heavy metals, phosphate, and nitrate ions from real wastewaters. This adsorption increased with increasing contact time. The equilibrium time was found to be 30 min for heavy metals and nitrate ions and 240 min for phosphate ions. After the adsorption process, the Pb(II) concentrations, as well as those of Cd(II), Cu(II), and Zn(II) were below the European drinking water norms concentrations. The percentage removal of heavy metals, nitrates, and phosphates from industrial wastewaters by dried plants was {proportional_to}94% for Cd{sup 2+}, {proportional_to}92% for Cu{sup 2+}, {proportional_to}99% for Pb{sup 2+}, {proportional_to}97% for Zn{sup 2+}, {proportional_to}100% for NO{sub 3}{sup -} and {proportional_to}77% for PO{sub 4}{sup 3-} ions. It is proved that dried plants can be one alternative source for low cost absorbents to remove heavy metals, nitrate, and phosphate ions from municipal and industrial wastewaters. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Application of carbon foam for heavy metal removal from industrial plating wastewater and toxicity evaluation of the adsorbent.

    Lee, Chang-Gu; Song, Mi-Kyung; Ryu, Jae-Chun; Park, Chanhyuk; Choi, Jae-Woo; Lee, Sang-Hyup

    2016-06-01

    Electroplating wastewater contains various types of toxic substances, such as heavy metals, solvents, and cleaning agents. Carbon foam was used as an adsorbent for the removal of heavy metals from real industrial plating wastewater. Its sorption capacity was compared with those of a commercial ion-exchange resin (BC258) and a heavy metal adsorbent (CupriSorb™) in a batch system. The experimental carbon foam has a considerably higher sorption capacity for Cr and Cu than commercial adsorbents for acid/alkali wastewater and cyanide wastewater. Additionally, cytotoxicity test showed that the newly developed adsorbent has low cytotoxic effects on three kinds of human cells. In a pilot plant, the carbon foam had higher sorption capacity for Cr (73.64 g kg(-1)) than for Cu (14.86 g kg(-1)) and Ni (7.74 g kg(-1)) during 350 h of operation time. Oxidation pretreatments using UV/hydrogen peroxide enhance heavy metal removal from plating wastewater containing cyanide compounds. PMID:26999028

  5. Sewage sludge ash to phosphate fertilizer by chlorination and thermal treatment: residence time requirements for heavy metal removal.

    Nowak, Benedikt; Wegerer, Harald; Aschenbrenner, Philipp; Rechberger, Helmut; Winter, Franz

    2012-01-01

    Heavy metal removal from sewage sludge ash can be performed by mixing the ash with environmentally compatible chlorides (e.g. CaCl2 or MgCl2) and water, pelletizing the mixture and treating the pellets in a rotary reactor at about 1000 degrees C. Thermogravimetry-mass spectroscopy, muffle oven tests (500-1150 degrees C) and investigations in a laboratory-scale rotary reactor (950-1050 degrees C, residence time 1-25 min) were carried out. In the rotary reactor, up to 97% of Cu, 95% Pb and 95% Zn can be removed at 1050 degrees C. As Cl release starts from 400 degrees C (obtained from thermogravimetry-mass spectrometry experiments), heavy metals are already removed partially within the heating period. This heavy metal removal can be described as being similar to a first-order rate law. To meet the limit values specified in the Austrian and German fertilizer ordinances, residence times of the order of minutes are sufficient at 950 degrees C. PMID:23393980

  6. Soil amendments for heavy metals removal from stormwater runoff discharging to environmentally sensitive areas

    Trenouth, William R.; Gharabaghi, Bahram

    2015-10-01

    Concentrations of dissolved metals in stormwater runoff from urbanized watersheds are much higher than established guidelines for the protection of aquatic life. Five potential soil amendment materials derived from affordable, abundant sources have been tested as filter media using shaker tests and were found to remove dissolved metals in stormwater runoff. Blast furnace (BF) slag and basic oxygenated furnace (BOF) slag from a steel mill, a drinking water treatment residual (DWTR) from a surface water treatment plant, goethite-rich overburden (IRON) from a coal mine, and woodchips (WC) were tested. The IRON and BOF amendments were shown to remove 46-98% of dissolved metals (Cr, Co, Cu, Pb, Ni, Zn) in repacked soil columns. Freundlich adsorption isotherm constants for six metals across five materials were calculated. Breakthrough curves of dissolved metals and total metal accumulation within the filter media were measured in column tests using synthetic runoff. A reduction in system performance over time occurred due to progressive saturation of the treatment media. Despite this, the top 7 cm of each filter media removed up to 72% of the dissolved metals. A calibrated HYDRUS-1D model was used to simulate long-term metal accumulation in the filter media, and model results suggest that for these metals a BOF filter media thickness as low as 15 cm can be used to improve stormwater quality to meet standards for up to twenty years. The treatment media evaluated in this research can be used to improve urban stormwater runoff discharging to environmentally sensitive areas (ESAs).

  7. Removal of some heavy metals from industrial waste water using polyacrylamide ferric antimonate as new ion exchange material

    Composite ion exchangers consist of one or more ion exchangers combined with another material, which can be inorganic or organic and may it be an ion exchanger. The reason for manufacturing a composite material is to produce a granular material, with sufficient strength for column use, from ion exchangers that do not form, or only form weak, granules themselves. Attempts in this study are focused to prepare composite ion exchangers for treatment of wastewater. Heavy metals when present in water in concentrations exceeding the permitted limits are injurious to the health. Hence, it is very important to treat such waters to remove the metal ions present before it is supplied for any useful purpose. Therefore, many investigations have studied to develop more effective process to treat such waste stream. Ion-exchange has been widely adopted in heavy metal containing wastewater and most of the ion-exchangers (i.e. ion-exchange media) currently being used are commercially mass-produced organic resins.Therefore, the main aim of this work is directed to find the optimum conditions for removal of some heavy metals from industrial waste water.1-Preparation of polyacrylamide ferric antimonate composite.2-Characterization of the prepared exchanger using IR spectra, X-ray diffraction pattern, DTA and TG analyses.3-Chemical stability, capacity and equilibrium measurements will be determined on the materials using at different conditions (ph heating temperature and reaction temperature).4-Kinetic studies of some heavy metals.5-Ion exchange isotherm.6-Breakthrough curves for removal of the investigated metal ions on the prepared exchanger under certain condition.

  8. Characterization of potassium hydroxide (KOH) modified hydrochars from different feedstocks for enhanced removal of heavy metals from water.

    Sun, Kejing; Tang, Jingchun; Gong, Yanyan; Zhang, Hairong

    2015-11-01

    Hydrochars produced from different feedstocks (sawdust, wheat straw, and corn stalk) via hydrothermal carbonization (HTC) and KOH modification were used as alternative adsorbents for aqueous heavy metals remediation. The chemical and physical properties of the hydrochars and KOH-treated hydrochars were characterized, and the ability of hydrochars for removal of heavy metals from aqueous solutions as a function of reaction time, pH, and initial contaminant concentration was tested. The results showed that KOH modification of hydrochars might have increased the aromatic and oxygen-containing functional groups, such as carboxyl groups, resulting in about 2-3 times increase of cadmium sorption capacity (30.40-40.78 mg/g) compared to that of unmodified hydrochars (13.92-14.52 mg/g). The sorption ability among different feedstocks after modification was as the following: sawdust > wheat straw > corn stack. Cadmium sorption kinetics on modified hydrochars could be interpreted with a pseudo-second order, and sorption isotherm was simulated with Langmuir adsorption model. High cadmium uptake on modified hydrochars was observed over the pH range of 4.0-8.0, while for other heavy metals (Pb(2+), Cu(2+), and Zn(2+)) the range was 4.0-6.0. In a multi-metal system, the sorption capacity of heavy metals by modified hydrochars was also higher than that by unmodified ones and followed the order of Pb(II) > Cu(II) > Cd(II) > Zn(II). The results suggest that KOH-modified hydrochars can be used as a low cost, environmental-friendly, and effective adsorbent for heavy metal removal from aqueous solutions. PMID:26081779

  9. Removal of SO42-, uranium and other heavy metal ions from simulated solution by sulfate reducing bacteria

    WANG Qing-liang; DING De-xin; HU E-ming; YU RUN-lan; QIU Guan-zhou

    2008-01-01

    In the case of in-situ leaching of uranium,the primitive geochemical environment for groundwater is changed since leachant is injected into the water bearing uranium deposit.This increases the concentration of SO42-,uranium and other heavy metal ions and results in the groundwater contamination.The effects of pH values of the simulated solution on the reduction of SO42- and the removal of uranium and other heavy metal ions by sulfate reducing bacteria(SRB) were studied.The results show that,when the pH value of the simulated solution is about 8,the reduction rate of SO42- by SRB and the removal rate of uranium,Mn2+,Zn2+,Pb2+ and Fe2+ will reach their highest values.A bioremediation technique for remediation of groundwater in in-situ leaching uranium mine can be developed.

  10. Studies on sorption, desorption, regeneration and reuse of sugar-beet pectin gels for heavy metal removal

    This work reports the effectiveness of sugar-beet pectin xerogels for the removal of heavy metals (cadmium, lead and copper) after multiple batch sorption-desorption cycles, with and without a gels regeneration step. Metals were recovered from xerogel beads without destroying their sorption capability and the beads were successfully reused (nine cycles) without significant loss in both biosorption capacity and biosorbent mass. Metals uptake levelled off or increased after using a 1 M CaCl2 regeneration step after each desorption. Calcium, as a regenerating agent, increased the stability and reusability of the gels repairing the damage caused by the acid and removing the excess protons after each elution providing new binding sites. Because of their excellent reusability, pectin xerogels are suitable for metal remediation technologies.

  11. Efficiency of compost in the removal of heavy metals from the industrial wastewater

    Kocasoy, Günay; Güvener, Zeynep

    2009-03-01

    Authorities have been applying very strict regulations for the treatment of industrial wastewater recently because of the threatening level of the environmental pollution faced. Industrial wastewater containing heavy metals is a threat to the public health because of the accumulation of the heavy metals in the aquatic life which is transferred to human bodies through the food chain. Therefore, recently, researchers have been oriented toward the practical use of adsorbents for the treatment of wastewater polluted by heavy metals. The aim of this research was to determine the retention capacity of compost for copper, zinc, nickel and chromium. For this purpose, experiments in batch-mixing reactors with initial metal concentrations ranging from 100 to 1,000 mg/l were carried. It was also observed that compost could repeatedly be used in metal sorption processes. The experiments conducted indicated that compost has high retention capacities for copper, zinc and nickel, but not for chromium. Thus, compost has been approved as a potential sorbent for copper, zinc and nickel and may find place in industrial applications. Thus, solid waste which is another source of significant environmental pollution will be reduced by being converted into a beneficial product compost.

  12. Novel biopolymer-coated hydroxyapatite foams for removing heavy-metals from polluted water

    Vila, M.; Sanchez-Salcedo, S.; Cicuendez, M.; Izquierdo-Barba, I. [Inorganic and BioInorganic Chemistry Department, Pharmacy Faculty, Universidad Complutense de Madrid, Plaza de Ramon y Cajal s/n, 28040 Madrid (Spain); Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN (Spain); Vallet-Regi, Maria, E-mail: vallet@farm.ucm.es [Inorganic and BioInorganic Chemistry Department, Pharmacy Faculty, Universidad Complutense de Madrid, Plaza de Ramon y Cajal s/n, 28040 Madrid (Spain); Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN (Spain)

    2011-08-15

    Highlights: {yields} 3D-macroporous biopolymer-coated hydroxyapatite (HA) foams as potential devices for the treatment of heavy metal ions. {yields} HA stable foams coated with biopolymers. {yields} Feasible advance in development of new, easy to handle and low cost water purifying methods. - Abstract: 3D-macroporous biopolymer-coated hydroxyapatite (HA) foams have been developed as potential devices for the treatment of lead, cadmium and copper contamination of consumable waters. These foams have exhibited a fast and effective ion metal immobilization into the HA structure after an in vitro treatment mimicking a serious water contamination case. To improve HA foam stability at contaminated aqueous solutions pH, as well as its handling and shape integrity the 3D-macroporous foams have been coated with biopolymers polycaprolactone (PCL) and gelatine cross-linked with glutaraldehyde (G/Glu). Metal ion immobilization tests have shown higher and fast heavy metals captured as function of hydrophilicity rate of biopolymer used. After an in vitro treatment, foam morphology integrity is guaranteed and the uptake of heavy metal ions rises up to 405 {mu}mol/g in the case of Pb{sup 2+}, 378 {mu}mol/g of Cu{sup 2+} and 316 {mu}mol/g of Cd{sup 2+}. These novel materials promise a feasible advance in development of new, easy to handle and low cost water purifying methods.

  13. Novel biopolymer-coated hydroxyapatite foams for removing heavy-metals from polluted water

    Highlights: → 3D-macroporous biopolymer-coated hydroxyapatite (HA) foams as potential devices for the treatment of heavy metal ions. → HA stable foams coated with biopolymers. → Feasible advance in development of new, easy to handle and low cost water purifying methods. - Abstract: 3D-macroporous biopolymer-coated hydroxyapatite (HA) foams have been developed as potential devices for the treatment of lead, cadmium and copper contamination of consumable waters. These foams have exhibited a fast and effective ion metal immobilization into the HA structure after an in vitro treatment mimicking a serious water contamination case. To improve HA foam stability at contaminated aqueous solutions pH, as well as its handling and shape integrity the 3D-macroporous foams have been coated with biopolymers polycaprolactone (PCL) and gelatine cross-linked with glutaraldehyde (G/Glu). Metal ion immobilization tests have shown higher and fast heavy metals captured as function of hydrophilicity rate of biopolymer used. After an in vitro treatment, foam morphology integrity is guaranteed and the uptake of heavy metal ions rises up to 405 μmol/g in the case of Pb2+, 378 μmol/g of Cu2+ and 316 μmol/g of Cd2+. These novel materials promise a feasible advance in development of new, easy to handle and low cost water purifying methods.

  14. Validity of manganese as a surrogate of heavy metals removal in constructed wetlands treating acidic mine water

    The evaluation of manganese as a surrogate for heavy metal behavior in two wetland treatment systems receiving acidic coal mine drainage in central Pennsylvania was investigated. The use of manganese as an indicator is based on physical/chemical treatment processes quite different from wetland treatment. The treatment systems represented one anoxic, subsurface flow system and one oxic surface flow system. Water quality parameters measured included pH, alkalinity, acidity, and a suite of metals. Correlation and linear regression analysis were used to evaluate the ability of a candidate predictor variable (indicator) to predict heavy metal concentrations and removal. The use of manganese as a predictor of effluent quality proved to be poor in both wetland treatment systems, as evidenced by low linear R2 values and negative correlations. Zinc emerged as the best predictor of the detectable heavy metals at the anoxic wetland. Zinc exhibited positive strong linear correlations with copper, cobalt, and nickel (R2 values of 0.843, 0.881, and 0.970, respectively). Effluent pH was a slightly better predictor of effluent copper levels in the anoxic wetland. Iron and cobalt effluent concentrations showed the only strong relationship (R2 value = 0.778) in the oxic system. The lack of good correlations with manganese strongly challenges its appropriateness as a surrogate for heavy metals in these systems

  15. Design and simulation of an activated sludge unit associated to a continuous reactor to remove heavy metals

    D`Avila, J.S.; Nascimento, R.R. [Ambientec Consultoria Ltda., Aracaju, SE (Brazil)

    1993-12-31

    A software was developed to design and simulate an activated sludge unit associated to a new technology to remove heavy metals from wastewater. In this process, a continuous high efficiency biphasic reactor operates by using particles of activated peat in conjugation with the sludge unit. The results obtained may be useful to increase the efficiency or to reduce the design and operational costs involved in a activated sludge unit. (author). 5 refs., 2 tabs.

  16. Removal of heavy metals from acid mine drainage (AMD) using coal fly ash, natural clinker and synthetic zeolites.

    Ríos, C A; Williams, C D; Roberts, C L

    2008-08-15

    Acid mine drainage (AMD) is a widespread environmental problem associated with both working and abandoned mining operations, resulting from the microbial oxidation of pyrite in presence of water and air, affording an acidic solution that contains toxic metal ions. The generation of AMD and release of dissolved heavy metals is an important concern facing the mining industry. The present study aimed at evaluating the use of low-cost sorbents like coal fly ash, natural clinker and synthetic zeolites to clean-up AMD generated at the Parys Mountain copper-lead-zinc deposit, Anglesey (North Wales), and to remove heavy metals and ammonium from AMD. pH played a very important role in the sorption/removal of the contaminants and a higher adsorbent ratio in the treatment of AMD promoted the increase of the pH, particularly using natural clinker-based faujasite (7.70-9.43) and the reduction of metal concentration. Na-phillipsite showed a lower efficiency as compared to that of faujasite. Selectivity of faujasite for metal removal was, in decreasing order, Fe>As>Pb>Zn>Cu>Ni>Cr. Based on these results, the use of these materials has the potential to provide improved methods for the treatment of AMD. PMID:18221835

  17. Evaluation of biosurfactants grown in corn oil by Rhodococcus rhodochrous on removing of heavy metal ion from aqueous solution

    Suryanti, Venty; Hastuti, Sri; Pujiastuti, Dwi

    2016-02-01

    The potential application of biosurfactants to remove heavy metal ion from aqueous solution by batch technique was examined. The glycolipids type biosurfactants were grown in a media containing of 20% v/v corn oil with 7 days of fermentation by Rhodococcus rhodochrous. The biosurfactants reduced the surface tension of water of about 51% from 62 mN/m to 30 mN/m. The biosurfactant increased the E24 of water-palm oil emulsion of about 55% from 43% to 97% and could maintain this E24 value of above 50% for up to 9 days. Heavy metal ion removal, in this case cadmium ion, by crude and patially purified biosurfactants has been investigated from aqueous solution at pH 6. Adsorption capacity of Cd(II) ion by crude biosurfactant with 5 and 10 minutes of contact times were 1.74 and 1.82 mg/g, respectively. Additionally, the adsorption capacity of Cd(II) ion by partially purified biosurfactant with 5 and 10 minutes of contact times were 0.79 and 1.34 mg/g, respectively. The results demonstrated that the adsorption capacity of Cd(II) ion by crude biosurfactant was higher than that of by partially purified biosurfactant. The results suggested that the biosurfactant could be used in the removal of heavy metal ions from aqueous solution.

  18. Evaluation of biosurfactants grown in corn oil by Rhodococcus rhodochrous on removing of heavy metal ion from aqueous solution

    The potential application of biosurfactants to remove heavy metal ion from aqueous solution by batch technique was examined. The glycolipids type biosurfactants were grown in a media containing of 20% v/v corn oil with 7 days of fermentation by Rhodococcus rhodochrous. The biosurfactants reduced the surface tension of water of about 51% from 62 mN/m to 30 mN/m. The biosurfactant increased the E24 of water-palm oil emulsion of about 55% from 43% to 97% and could maintain this E24 value of above 50% for up to 9 days. Heavy metal ion removal, in this case cadmium ion, by crude and patially purified biosurfactants has been investigated from aqueous solution at pH 6. Adsorption capacity of Cd(II) ion by crude biosurfactant with 5 and 10 minutes of contact times were 1.74 and 1.82 mg/g, respectively. Additionally, the adsorption capacity of Cd(II) ion by partially purified biosurfactant with 5 and 10 minutes of contact times were 0.79 and 1.34 mg/g, respectively. The results demonstrated that the adsorption capacity of Cd(II) ion by crude biosurfactant was higher than that of by partially purified biosurfactant. The results suggested that the biosurfactant could be used in the removal of heavy metal ions from aqueous solution

  19. Evaluation of biosurfactants grown in corn oil by Rhodococcus rhodochrous on removing of heavy metal ion from aqueous solution

    Suryanti, Venty, E-mail: venty@mipa.uns.ac.id; Hastuti, Sri; Pujiastuti, Dwi [Department of Chemistry, Faculty of Mathematics and Natural Sciences, Sebelas Maret University Jl. Ir. Sutami 36A, Surakarta, Central Java 57126 (Indonesia)

    2016-02-08

    The potential application of biosurfactants to remove heavy metal ion from aqueous solution by batch technique was examined. The glycolipids type biosurfactants were grown in a media containing of 20% v/v corn oil with 7 days of fermentation by Rhodococcus rhodochrous. The biosurfactants reduced the surface tension of water of about 51% from 62 mN/m to 30 mN/m. The biosurfactant increased the E24 of water-palm oil emulsion of about 55% from 43% to 97% and could maintain this E24 value of above 50% for up to 9 days. Heavy metal ion removal, in this case cadmium ion, by crude and patially purified biosurfactants has been investigated from aqueous solution at pH 6. Adsorption capacity of Cd(II) ion by crude biosurfactant with 5 and 10 minutes of contact times were 1.74 and 1.82 mg/g, respectively. Additionally, the adsorption capacity of Cd(II) ion by partially purified biosurfactant with 5 and 10 minutes of contact times were 0.79 and 1.34 mg/g, respectively. The results demonstrated that the adsorption capacity of Cd(II) ion by crude biosurfactant was higher than that of by partially purified biosurfactant. The results suggested that the biosurfactant could be used in the removal of heavy metal ions from aqueous solution.

  20. Efficiency of Aluminum and Iron Electrodes for the Removal of Heavy Metals [(Ni (II), Pb (II), Cd (II)] by Electrocoagulation Method

    Khosa, Muhammad Kaleem; Jamal, Muhammad Asghar; Hussain, Amira; Muneer, Majid; Zia, Khalid Mahmood [Government College Univ., Faisalabad (Pakistan); Hafeez, Samia [Bahaud-din-Zakariya Univ., Multan (Pakistan)

    2013-06-15

    Electrocoagulation (EC) technique is applied for the treatment of wastewater containing heavy metals ions such as nickel (Ni), lead (Pb) and cadmium (Cd) by using sacrificial anodes corrode to release active coagulant flocs usually aluminium or iron cations into the solution. During electrolytic reactions hydrogen gas evolve at the cathode. All the experiments were carried out in Batch mode. The tank was filled with synthetic wastewater containing heavy metals and efficiency of electrocoagulation in combination with aluminum and iron electrodes were investigated for removal of such metals. Several parameters, such as contact time, pH, electro-coagulant concentration, and current density were optimized to achieve maximum removal efficiency (%). The concentrations of heavy metals were determined by using Atomic Absorption Spectroscopy (AAS). It is found that the electro-coagulation process has potential to be utilized for the cost-effective removal of heavy metals from wastewater specially using iron electrodes in terms of high removal efficiencies and operating cost.

  1. Efficiency of Aluminum and Iron Electrodes for the Removal of Heavy Metals [(Ni (II), Pb (II), Cd (II)] by Electrocoagulation Method

    Electrocoagulation (EC) technique is applied for the treatment of wastewater containing heavy metals ions such as nickel (Ni), lead (Pb) and cadmium (Cd) by using sacrificial anodes corrode to release active coagulant flocs usually aluminium or iron cations into the solution. During electrolytic reactions hydrogen gas evolve at the cathode. All the experiments were carried out in Batch mode. The tank was filled with synthetic wastewater containing heavy metals and efficiency of electrocoagulation in combination with aluminum and iron electrodes were investigated for removal of such metals. Several parameters, such as contact time, pH, electro-coagulant concentration, and current density were optimized to achieve maximum removal efficiency (%). The concentrations of heavy metals were determined by using Atomic Absorption Spectroscopy (AAS). It is found that the electro-coagulation process has potential to be utilized for the cost-effective removal of heavy metals from wastewater specially using iron electrodes in terms of high removal efficiencies and operating cost

  2. Selective removals of heavy metals (Pb(2+), Cu(2+), and Cd(2+)) from wastewater by gelation with alginate for effective metal recovery.

    Wang, Fei; Lu, Xingwen; Li, Xiao-Yan

    2016-05-01

    A novel method that uses the aqueous sodium alginate solution for direct gelation with metal ions is developed for effective removal and recovery of heavy metals from industrial wastewater. The experimental study was conducted on Pb(2+), Cu(2+), and Cd(2+) as the model heavy metals. The results show that gels can be formed rapidly between the metals and alginate in less than 10min and the gelation rates fit well with the pseudo second-order kinetic model. The optimum dosing ratio of alginate to the metal ions was found to be between 2:1 and 3:1 for removing Pb(2+) and around 4:1 for removing Cu(2+) and Cd(2+) from wastewater, and the metal removal efficiency by gelation increased as the solution pH increased. Alginate exhibited a higher gelation affinity toward Pb(2+) than Cu(2+) and Cd(2+), which allowed a selective removal of Pb(2+) from the wastewater in the presence of Cu(2+) and Cd(2+) ions. Chemical analysis of the gels suggests that the gelation mainly occurred between the metal ions and the COO(-) and OH groups on alginate. By simple calcination of the metal-laden gels at 700°C for 1h, the heavy metals can be well recovered as valuable resources. The metals obtained after the thermal treatment are in the form of PbO, CuO, and CdO nanopowders with crystal sizes of around 150, 50, and 100nm, respectively. PMID:26808245

  3. Removal of dissolved heavy metals from pre-settled stormwater runoff by iron-oxide coated sand (IOCS)

    Møller, J.; Ledin, Anna; Mikkelsen, Peter Steen

    2002-01-01

    Sorption to iron-oxide coated sand (IOCS) is a promosing technology for removal of the dissolved heavy metal fraction in stormwater runoff. The development of a new technology is necessary since studies of stormwater runoff from traffic areas indicate that an oil separator and detention pond may...... leterature (Pb=20, Cu=40, Zn=110, and Cr=15 ppb). Column experiments were conducted to test the influence of the infiltration rate (1 or 3 m/h) and the type of iron(hydr)oxide mineral (amorphous ferrihydrite and goethite coated sand). The results show that at least 90% of lead, copper and zinc can be removed...

  4. Synthesis and Characterization of Iron Oxide Nanoparticles and Applications in the Removal of Heavy Metals from Industrial Wastewater

    Zuolian Cheng

    2012-01-01

    Full Text Available This study investigated the applicability of maghemite (γ-Fe2O3 nanoparticles for the selective removal of toxic heavy metals from electroplating wastewater. The maghemite nanoparticles of 60 nm were synthesized using a coprecipitation method and characterized by X-ray diffraction (XRD and scanning electron microscopy (SEM equipped with energy dispersive X-ray spectroscopy (EDX. Batch experiments were carried out for the removal of Pb2+ ions from aqueous solutions by maghemite nanoparticles. The effects of contact time, initial concentration of Pb2+ ions, solution pH, and salinity on the amount of Pb2+ removed were investigated. The adsorption process was found to be highly pH dependent, which made the nanoparticles selectively adsorb this metal from wastewater. The adsorption of Pb2+ reached equilibrium rapidly within 15 min and the adsorption data were well fitted with the Langmuir isotherm.

  5. Characterisation and removal of heavy metals in tannery effluents through the use of local materials

    Robertsson, Jonas; Andersson, Camilla

    2014-01-01

    Chromium and other heavy metals are known to cause issues related to human and environmental health when they occur in high concentrations in ecosystems. Chromium poses a particularly large threat if it occurs in its hexavalent form, Cr(VI), as it is highly reactive and carcinogenic. The aim of this project was to investigate the wastewater emitted from a tannery in Liwonde, Malawi, with respect to the metals Cr, Al, Cd, Cu, Fe, Mn, Pb and Zn, and to reduce the concentrations using locally av...

  6. Heavy metals removal from aqueous environments by electrocoagulation process– a systematic review

    Bazrafshan, Edris; Mohammadi, Leili; Ansari-Moghaddam, Alireza; MAHVI, Amir Hossein

    2015-01-01

    Heavy metals pollution has become a more serious environmental problem in the last several decades as a result releasing toxic materials into the environment. Various techniques such as physical, chemical, biological, advanced oxidation and electrochemical processes were used for the treatment of domestic, industrial and agricultural effluents. The commonly used conventional biological treatments processes are not only time consuming but also need large operational area. Accordingly, it seems...

  7. Parthenium hysterophorus: Novel adsorbent for the removal of heavy metals and dyes

    S.A. Bapat; D.K. Jaspal

    2016-01-01

    Heavy metals and dyes are major contributors in contamination of water streams. These contaminants enter into our eco- system, thus posing a significant threat to public health, ecological equilibrium and environment. Thus a combined discharge of these contaminants results in water pollution with high chemical oxygen demand, biological oxygen demand, color, particulate matter, suspended particles and odor. The mounting pollution of the water bodies has attracted attention of the researchers t...

  8. Heavy metal removal mechanisms of sorptive filter materials for road runoff treatment and remobilization under de-icing salt applications.

    Huber, Maximilian; Hilbig, Harald; Badenberg, Sophia C; Fassnacht, Julius; Drewes, Jörg E; Helmreich, Brigitte

    2016-10-01

    The objective of this research study was to elucidate the removal and remobilization behaviors of five heavy metals (i.e., Cd, Cu, Ni, Pb, and Zn) that had been fixed onto sorptive filter materials used in decentralized stormwater treatment systems receiving traffic area runoff. Six filter materials (i.e., granular activated carbon, a mixture of granular activated alumina and porous concrete, granular activated lignite, half-burnt dolomite, and two granular ferric hydroxides) were evaluated in column experiments. First, a simultaneous preloading with the heavy metals was performed for each filter material. Subsequently, the remobilization effect was tested by three de-icing salt experiments in duplicate using pure NaCl, a mixture of NaCl and CaCl2, and a mixture of NaCl and MgCl2. Three layers of each column were separated to specify the attenuation of heavy metals as a function of depth. Cu and Pb were retained best by most of the selected filter materials, and Cu was often released the least of all metals by the three de-icing salts. The mixture of NaCl and CaCl2 resulted in a stronger effect upon remobilization than the other two de-icing salts. For the material with the highest retention, the effect of the preloading level upon remobilization was measured. The removal mechanisms of all filter materials were determined by advanced laboratory methods. For example, the different intrusions of heavy metals into the particles were determined. Findings of this study can result in improved filter materials used in decentralized stormwater treatment systems. PMID:27423405

  9. Polydopamine-mediated surface-functionalization of graphene oxide for heavy metal ions removal

    Dong, Zhihui [Nano-Bionics Division and i-LAB, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123 (China); University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100049 (China); Zhang, Feng; Wang, Dong; Liu, Xia [Nano-Bionics Division and i-LAB, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123 (China); Jin, Jian, E-mail: jjin2009@sinano.ac.cn [Nano-Bionics Division and i-LAB, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123 (China)

    2015-04-15

    By utilizing polydopamine (PD) nano-thick interlayer as mediator, polyethylenimine (PEI) brushes with abundant amine groups were grafted onto the surface of PD coated graphene oxide (GO) uniformly via a Michael-Addition reaction and produced a PEI–PD/GO composite nanosheets. The PEI–PD/GO composite exhibited an improved performance for adsorption of heavy metal ions as compared to PEI-coated GO and pure GO. The adsorption capacities for Cu{sup 2+}, Cd{sup 2+}, Pb{sup 2+}, Hg{sup 2+} are up to 87, 106, 197, and 110 mg/g, respectively. To further make the GO based composite operable, PEI–PD/RGO aerogel was prepared through hydrothermal and achieved a high surface area up to 373 m{sup 2}/g. Although the adsorption capacity of PEI–PD/RGO aerogel for heavy metal ions decreases a little as compared to PEI–PD/GO composite dispersion (38, 32, 95, 113 mg/g corresponding to Cu{sup 2+}, Cd{sup 2+}, Pb{sup 2+}, and Hg{sup 2+}, respectively), it could be recycled several times in a simple way by releasing adsorbed metal ions, indicating its potential application for cleaning wastewater. - Graphical abstract: Polyethylenimine (PEI) brushes were grafted onto the surface of graphene oxide (GO) uniformly via a Michael-Addition reaction between the PEI and polydopamine interlayer coated on GO surface. The PEI–PD/GO composite exhibited an improved performance for adsorption of heavy metal ions compared to PEI-coated GO and pure GO. - Highlights: • We prepared polyethylenimine grafted polydopamine-mediated graphene oxide composites. • Introduction of PD layer increases metal ions adsorption capacity. • PEI–PD/RGO aerogel exhibited a superior adsorption performance. • PEI–PD/RGO aerogel can be recycled several times in a simple way.

  10. Polydopamine-mediated surface-functionalization of graphene oxide for heavy metal ions removal

    By utilizing polydopamine (PD) nano-thick interlayer as mediator, polyethylenimine (PEI) brushes with abundant amine groups were grafted onto the surface of PD coated graphene oxide (GO) uniformly via a Michael-Addition reaction and produced a PEI–PD/GO composite nanosheets. The PEI–PD/GO composite exhibited an improved performance for adsorption of heavy metal ions as compared to PEI-coated GO and pure GO. The adsorption capacities for Cu2+, Cd2+, Pb2+, Hg2+ are up to 87, 106, 197, and 110 mg/g, respectively. To further make the GO based composite operable, PEI–PD/RGO aerogel was prepared through hydrothermal and achieved a high surface area up to 373 m2/g. Although the adsorption capacity of PEI–PD/RGO aerogel for heavy metal ions decreases a little as compared to PEI–PD/GO composite dispersion (38, 32, 95, 113 mg/g corresponding to Cu2+, Cd2+, Pb2+, and Hg2+, respectively), it could be recycled several times in a simple way by releasing adsorbed metal ions, indicating its potential application for cleaning wastewater. - Graphical abstract: Polyethylenimine (PEI) brushes were grafted onto the surface of graphene oxide (GO) uniformly via a Michael-Addition reaction between the PEI and polydopamine interlayer coated on GO surface. The PEI–PD/GO composite exhibited an improved performance for adsorption of heavy metal ions compared to PEI-coated GO and pure GO. - Highlights: • We prepared polyethylenimine grafted polydopamine-mediated graphene oxide composites. • Introduction of PD layer increases metal ions adsorption capacity. • PEI–PD/RGO aerogel exhibited a superior adsorption performance. • PEI–PD/RGO aerogel can be recycled several times in a simple way

  11. Effects of modified zeolite on the removal and stabilization of heavy metals in contaminated lake sediment using BCR sequential extraction.

    Wen, Jia; Yi, Yuanjie; Zeng, Guangming

    2016-08-01

    Sediment can be applied on land as a soil conditioner. However, toxic substances such as heavy metals within the sediment often lead to soil contamination if no proper management is conducted prior to land application. In order to reduce the bioavailable portion of heavy metals such as Pb, Cu, Zn and Cd, zeolite as a kind of stabilizer was investigated on the effect of metal stabilization in sediment. Zeolite was firstly modified and screened to get the best condition for removal of heavy metals. Results showed that the granulated zeolite with NaCl conditioning had the highest CEC and metal sorption. Using BCR sequential extraction, the selected modified zeolite effectively stabilized Pb, Cu, Zn and Cd in sediment to different extents. It was most suitable for Cd stabilization by reducing its acid exchangeable fraction while increasing the contents of the reducible and residual fractions. Modified zeolite also immobilized Cu, Zn and Pb in sediment by enhancing one stable fraction while decreasing the acid exchangeable fraction. PMID:27136618

  12. Influences of thermal decontamination on mercury removal, soil properties, and repartitioning of coexisting heavy metals.

    Huang, Yu-Tuan; Hseu, Zeng-Yei; Hsi, Hsing-Cheng

    2011-08-01

    Thermal treatment is a useful tool to remove Hg from contaminated soils. However, thermal treatment may greatly alter the soil properties and cause the coexisting contaminants, especially trace metals, to transform and repartition. The metal repartitioning may increase the difficulty in the subsequent process of a treatment train approach. In this study, three Hg-contaminated soils were thermally treated to evaluate the effects of treating temperature and duration on Hg removal. Thermogravimetric analysis was performed to project the suitable heating parameters for subsequent bench-scale fixed-bed operation. Results showed that thermal decontamination at temperature>400°C successfully lowered the Hg content toheavy metals tended to transform into acid-extractable, organic-matter bound, and residual forms from the Fe/Mn oxide bound form. These results suggest that thermal treatment may markedly influence the effectiveness of subsequent decontamination methods, such as acid washing or solvent extraction. PMID:21624629

  13. Synthesis and characterization of radiation grafted films for removal of arsenic and some heavy metals from contaminated water

    Grafting of styrene/maleic anhydride and methyl methacrylate/maleic anhydride binary monomers onto the low density polyethylene film was performed using the γ-ray irradiation technique. Then, the synthesized grafted films were treated with different ammonia derivatives for developing chelating functionalization. These chelating products were characterized by the gravimetric method as well as by the Fourier transformed infrared spectroscopic method, and were used for removal of arsenic and some heavy metals from aqueous solutions. The optimum absorbed dose of 30 kGy reveals the graft yielding of about 325% in the films. Uptake of arsenic and some heavy-metal ions (Cr(III), Mn(II), Fe(III), Ni(II), Cu(II) and Pb(II)) from contaminated water by the chelating functionalized films (CFF) was examined by an atomic absorption spectrophotometer. The maximum arsenic removal capacity of 5062 mg/kg has been observed for the film treated with hydroxylamine hydrochloride. The CFF prepared by semicarbazide and thiol analogs show affinity toward the metal ions with an order: Cu(II)>Fe(III)>Mn(II) etc. The results obtained from this study indicate that the functionalized films show good chelating and ion-exchange property for metal ions. - Highlights: ► Optimization of radiation dose for grafting reaction of polyethylene with binary monomers. ► Chelating functionalization of grafted film with various amine compounds. ► Characterization of both grafted and chelating functionalized films. ► Proposed mechanism for both grafting and chelating functionalization reaction. ► Application of the synthesized films for the removal of arsenic and some heavy metals from contaminated water.

  14. Hydrogen peroxide modification enhances the ability of biochar (hydrochar) produced from hydrothermal carbonization of peanut hull to remove aqueous heavy metals: Batch and column tests

    Experimental and modeling investigations were conducted to examine the effect of hydrogen peroxide treatment on hydrothermally produced biochar (hydrochar) from peanut hull to remove aqueous heavy metals. Characterization measurements showed that hydrogen peroxide modification increased the oxygen-c...

  15. Effects of operating conditions on the removal of heavy metals by zeolite in fixed bed reactors

    This work investigates the effects of flow rate (5-15 Bed Volumes/h), particle size (0.8-1.7 mm), concentration (0.005-0.02 N) and Na+-enrichment of natural clinoptilolite on the removal efficiency of Pb2+, Cu2+, Fe3+ and Cr3+ in aqueous solutions. Ion exchange is performed in an upflow fixed bed reactor. The removal efficiency is increased with decreasing flow rate, particle size and concentration and is improved by a factor of 2-10, depending on the specific metal. The modification of the natural sample is favorable, leading to an increase of removal efficiency by 32-100%. For the experimental conditions examined, removal efficiency order is the following: Pb2+>Cr3+>Fe3+≥Cu2+. Finally, the operation is influenced by the studied parameters, following the order: concentration>volumetric flow rate>particle size>modification of the material

  16. Changes in nutrient profile of soil subjected to bioleaching for removal of heavy metals using Acidithiobacillus thiooxidans

    NareshKumar, R. [Centre for Environmental Studies, Anna University, Chennai 600025 (India)], E-mail: nareshkrish@hotmail.com; Nagendran, R. [Centre for Environmental Studies, Anna University, Chennai 600025 (India)

    2008-08-15

    Studies were carried out to assess changes in nitrogen, phosphorus and potassium contents in soil during bioleaching of heavy metals from soil contaminated by tannery effluents. Indigenous sulfur oxidizing bacteria Acidithiobacillus thiooxidans isolated from the contaminated soil were used for bioremediation. Solubilization efficiency of chromium, cadmium, copper and zinc from soil was 88, 93, 92 and 97%, respectively. However, loss of nitrogen, phosphorus and potassium from the soil was 30, 70 and 68%, respectively. These findings indicate that despite its high potential for removal of heavy metals from contaminated soils, bioleaching results in undesirable dissolution/loss of essential plant nutrients. This aspect warrants urgent attention and detailed studies to evaluate the appropriateness of the technique for field application.

  17. Changes in nutrient profile of soil subjected to bioleaching for removal of heavy metals using Acidithiobacillus thiooxidans

    Studies were carried out to assess changes in nitrogen, phosphorus and potassium contents in soil during bioleaching of heavy metals from soil contaminated by tannery effluents. Indigenous sulfur oxidizing bacteria Acidithiobacillus thiooxidans isolated from the contaminated soil were used for bioremediation. Solubilization efficiency of chromium, cadmium, copper and zinc from soil was 88, 93, 92 and 97%, respectively. However, loss of nitrogen, phosphorus and potassium from the soil was 30, 70 and 68%, respectively. These findings indicate that despite its high potential for removal of heavy metals from contaminated soils, bioleaching results in undesirable dissolution/loss of essential plant nutrients. This aspect warrants urgent attention and detailed studies to evaluate the appropriateness of the technique for field application

  18. Crayfish Carapace Micro-powder (CCM: A Novel and Efficient Adsorbent for Heavy Metal Ion Removal from Wastewater

    Xiaodong Zheng

    2010-06-01

    Full Text Available Crayfish carapace, a plentiful waste in China, was applied to remove divalent heavy metal ions—copper (Cu, cadmium (Cd, zinc (Zn, and lead (Pb—from wastewater. The adsorption capacities of crayfish carapace micro-powder (CCM for heavy metal ions were studied with adsorbent dosages ranging from 0.5–2.5 g/L and with initial metal concentrations ranging from 50–250 mg/L. CCM particle size, initial solution pH (from 2.5–6.5, temperature (from 25–65 °C and calcium level (from 3.5–21.5% were also varied in batch mode. The results indicated that the adsorption capacity increases with both decreasing particle size and increasing calcium level of the crayfish carapace. The kinetic studies indicated that the adsorption could be complete within 2 h, and that the data correlated with the pseudo-second-order model. CCM recorded maximum uptakes of 200, 217.39, 80, and 322.58 mg/g for Cu, Cd, Zn, and Pb, respectively. The adsorption capacities and removal efficiencies of CCM for metal ions were three-times higher than those of chitin and chitosan extracted from the CCM.

  19. Fabrication of chelating diethylenetriaminated pan micro and nano fibers for heavy metal removal

    Abdouss Majid

    2012-01-01

    Full Text Available In this study, commercial acrylic fibers were modified with diethylenetriamine to prepare metal chelating fibers. The effects of process parameters on the efficiency of the reaction were investigated. FTIR spectroscopy and TGA analysis were used to confirm the chemical changes made to the fibers during the reaction. The ability of the modified fibers for removal of Pb (II, Cu (II and Ce (IV ions from aqueous media was determined. The modified fibers showed a slight decrease in mechanical properties compared to raw ones. Furthermore, the acrylic micro fibers were electrospun to nanofibers and the ability of modified nanofibers for the adsorption of the metal ions was studied.

  20. Assessment of electrokinetic removal of heavy metals from soils by sequential extraction analysis.

    Reddy, K R; Xu, C Y; Chinthamreddy, S

    2001-06-29

    Electrokinetic remediation of metal-contaminated soils is strongly affected by soil-type and chemical species of contaminants. This paper investigates the speciation and extent of migration of heavy metals in soils during electrokinetic remediation. Laboratory electrokinetic experiments were conducted using two diverse soils, kaolin and glacial till, contaminated with chromium as either Cr(III) or Cr(VI). Initial total chromium concentrations were maintained at 1000mg/kg. In addition, Ni(II) and Cd(II) were used in concentrations of 500 and 250mg/kg, respectively. The contaminated soils were subjected to a voltage gradient of 1 VDC/cm for over 200h. The extent of migration of contaminants after the electric potential application was determined. Sequential extractions were performed on the contaminated soils before and after electrokinetic treatment to provide an understanding of the distribution of the contaminants in the soils. The initial speciation of contaminants was found to depend on the soil composition as well as the type and amounts of different contaminants present. When the initial form of chromium was Cr(III), exchangeable and soluble fractions of Cr, Ni, and Cd ranged from 10 to 65% in kaolin; however, these fractions ranged from 0 to 4% in glacial till. When the initial form of chromium was Cr(VI), the exchangeable and soluble fractions of Cr, Ni and Cd ranged from 66 to 80% in kaolin. In glacial till, however, the exchangeable and soluble fraction for Cr was 38% and Ni and Cd fractions were 2 and 10%, respectively. The remainder of the contaminants existed as the complex and precipitate fractions. During electrokinetic remediation, Cr(VI) migrated towards the anode, whereas Cr(III), Ni(II) and Cd(II) migrated towards the cathode. The speciation of contaminants after electrokinetic treatment showed that significant change in exchangeable and soluble fractions occurred. In kaolin, exchangeable and soluble Cr(III), Ni(II), and Cd(II) decreased near the

  1. Removal of dissolved heavy metals from pre-settled stormwater runoff by iron-oxide coated sand (IOCS)

    Møller, J.; Ledin, Anna; Mikkelsen, Peter Steen

    2002-01-01

    Sorption to iron-oxide coated sand (IOCS) is a promosing technology for removal of the dissolved heavy metal fraction in stormwater runoff. The development of a new technology is necessary since studies of stormwater runoff from traffic areas indicate that an oil separator and detention pond may...... not guarantee that emission limit values set by the Danish EPA are satisfied. Runoff water was sampled from an urban highway, allowed to settle for 24 hours to simulate the effect of a detention pond, and finally spiked with metals to ensure concentration levels similar to high levels reported in the...... leterature (Pb=20, Cu=40, Zn=110, and Cr=15 ppb). Column experiments were conducted to test the influence of the infiltration rate (1 or 3 m/h) and the type of iron(hydr)oxide mineral (amorphous ferrihydrite and goethite coated sand). The results show that at least 90% of lead, copper and zinc can be removed...

  2. Long Term Estimates of Removal of Heavy Metals and PAH in Retention Basins

    Larsen, Torben; Neerup-Jensen, O.

    2004-01-01

    The paper describes a method for the long-term simulation of the discharge of pollutants to the environment from storm sewer overflows in combined sewer systems, which have a connected retention basins. This study covers heavy metals (Cd, Cu, Ni, Pb, Zn) and PAH. The method includes both the...... influence of the flow-dependant sedimentation and the variation of the settling velocity of the particles. The results show that including these effects lead to significant lower discharges of pollutants compared to conventional methods of estimation. As an example computations with a spectrum of basins...

  3. Heavy metal sorption by microalgae

    Sandau, E. [IGV - Inst. fuer Getreideverarbeitung GmbH, Bergholz-Rehbruecke (Germany); Sandau, P. [IGV - Inst. fuer Getreideverarbeitung GmbH, Bergholz-Rehbruecke (Germany); Pulz, O. [IGV - Inst. fuer Getreideverarbeitung GmbH, Bergholz-Rehbruecke (Germany)

    1996-12-31

    Viable microalgae are known to be able to accumulate heavy metals (bioaccumulation). Against a background of the increasing environmental risks caused by heavy metals, the microalgae Chlorella vulgaris and Spirulina platensis and their potential for the biological removal of heavy metals from aqueous solutions were taken as an example for investigation. Small-scale cultivation tests (50 l) with Cd-resistant cells of Chlorella vulgaris have shown that approx. 40% of the added 10 mg Cd/l was removed from the solution within seven days. At this heavy metal concentration sensitive cells died. Non-viable microalgae are able to eliminate heavy metal ions in a short time by biosorption in uncomplicated systems, without any toxicity problems. Compared with original biomasses, the sorption capacity of microalgal by-products changes only insignificantly. Their low price makes them economical. (orig.)

  4. Heavy metal sorption by microalgae

    Viable microalgae are known to be able to accumulate heavy metals (bioaccumulation). Against a background of the increasing environmental risks caused by heavy metals, the microalgae Chlorella vulgaris and Spirulina platensis and their potential for the biological removal of heavy metals from aqueous solutions were taken as an example for investigation. Small-scale cultivation tests (50 l) with Cd-resistant cells of Chlorella vulgaris have shown that approx. 40% of the added 10 mg Cd/l was removed from the solution within seven days. At this heavy metal concentration sensitive cells died. Non-viable microalgae are able to eliminate heavy metal ions in a short time by biosorption in uncomplicated systems, without any toxicity problems. Compared with original biomasses, the sorption capacity of microalgal by-products changes only insignificantly. Their low price makes them economical. (orig.)

  5. Removal of heavy metals from Water Rinsing of Plating Baths by Electrodialysis

    Delimi R.

    2013-04-01

    Full Text Available During the chromic plating of parts, the baths become more and more poor in chromic acid and rich in metallic impurities such as Cu2+, Zn2+, Fe3+ and Cr3+ which makes the bath useless. Also, the water used to rinse parts contains chromic acid and metallic impurities. As it is known that chromic acid is relatively expensive and very toxic, so its recovery has double interest: economic and environmental. Its reuse is possible after removal of metallic impurities. In this work, we studied the possibility of metallic impurities elimination from the chromic acid. The influence of the current density and the circulating solution flow rate on the process efficiency has been studied. The elimination rates obtained in the presence of ion exchange textile are superior to those obtained in the absence of textile. The analysis of the results showed that for the three metallic impurities studied (Cu2+, Fe3+ and Zn2+, the purification rate increases versus the applied current density and solution flow rate. The importance of the elimination of the three metal cations is as the following order: Cu2+ >Zn2+ >Fe3+.

  6. The application of polymer inclusive membranes for removal of heavy metal ions from waste solutions

    B. Gajda

    2012-12-01

    Full Text Available Purpose: The aim of the conducted studies was to determine the possibility of selective separation and precipitation of metal ions from polimetalic solution containing nickel(II, cobalt(II, cadmium(II and zinc(II cations using polymer inclusive membranes. 1-decylimidazole was used in membrane as a carrier of ions. The influence of chloride anions concentration on the process has also been investigated.Design/methodology/approach: Polymer inclusive membranes (PIM containing cellulose acetate as a matrix, orto-nitrophenyl octyl ether (ONPOE as a plasticizer and 1-decylimidazole as a carrier were used in investigations. The membrane processes were carried out in a membrane module for 24 hours.Findings: The results obtained point out a significant influence of chloride anions concentration on separation process of certain metal ions. It was observed that zinc(II ions are isolated most effectively from the solution containing 2M of chloride anions. About 88% of Zn(II, 5.5% of Co(II, 6.5% of Cd(II and below 1% of Ni(II were separated from such a solution.Research limitations/implications: The obtained results show that it is possibility of the selective extraction of heavy metal ions from polymetallic chloride solutions in membrane processes. The aqueous solution containing 2M of chloride ions was used in the investigation.Practical implications: The results show that Zn(II can be effectively recovered from solutions containing Co(II, Cd(II and Ni(II. This process would allow the utilization of waste solutions containing the heavy metal ions. The results of the study presented in the paper can be used in the utilization process of the spent batteries and accumulators.Originality/value: The innovative issue shown in this paper concerns the usage of 1-decylimidazole in selective separation of nickel(II, cobalt(II, cadmium(II and zinc(II ions in membrane process using PIM.

  7. Environmental Remediation and Application of Nanoscale Zero-Valent Iron and Its Composites for the Removal of Heavy Metal Ions: A Review.

    Zou, Yidong; Wang, Xiangxue; Khan, Ayub; Wang, Pengyi; Liu, Yunhai; Alsaedi, Ahmed; Hayat, Tasawar; Wang, Xiangke

    2016-07-19

    The presence of heavy metals in the industrial effluents has recently been a challenging issue for human health. Efficient removal of heavy metal ions from environment is one of the most important issues from biological and environmental point of view, and many studies have been devoted to investigate the environmental behavior of nanoscale zerovalent iron (NZVI) for the removal of toxic heavy metal ions, present both in the surface and underground wastewater. The aim of this review is to show the excellent removal capacity and environmental remediation of NZVI-based materials for various heavy metal ions. A new look on NZVI-based materials (e.g., modified or matrix-supported NZVI materials) and possible interaction mechanism (e.g., adsorption, reduction and oxidation) and the latest environmental application. The effects of various environmental conditions (e.g., pH, temperature, coexisting oxy-anions and cations) and potential problems for the removal of heavy metal ions on NZVI-based materials with the DFT theoretical calculations and EXAFS technology are discussed. Research shows that NZVI-based materials have satisfactory removal capacities for heavy metal ions and play an important role in the environmental pollution cleanup. Possible improvement of NZVI-based materials and potential areas for future applications in environment remediation are also proposed. PMID:27331413

  8. Simultaneous removal of organic compounds and heavy metals from soils by electrokinetic remediation with a modified cyclodextrin.

    Maturi, Kranti; Reddy, Krishna R

    2006-05-01

    Thousands of sites are contaminated with both heavy metals and organic compounds and these sites pose a major threat to public health and the environment. Previous studies have shown that electrokinetic remediation has potential to remove heavy metals and organic compounds when they exist individually in low permeability soils. This paper presents the feasibility of using cyclodextrins in electrokinetic remediation for the simultaneous removal of heavy metals and polycyclic aromatic hydrocarbons (PAHs) from low permeability soils. Kaolin was selected as a model low permeability soil and it was spiked with phenanthrene as well as nickel at concentrations of 500 mg kg-1 each to simulate typical mixed field contamination. Bench-scale electrokinetic experiments were conducted using hydroxypropyl beta-cyclodextrin (HPCD) at low (1%) and high (10%) concentrations and using deionized water in control test. A periodic voltage gradient of 2VDC cm-1 (with 5 d on and 2 d off) was applied to all the tests, and 0.01 M NaOH was added during the experiments to maintain neutral pH conditions at anode. In all tests, nickel migrated as Ni2+ ions towards the cathode and most of it was precipitated as Ni(OH)2 within the soil close to the cathode due to high pH condition generated by electrolysis reaction. The solubility of phenanthrene in the flushing solution and the amount of electroosmotic flow controlled the migration and removal of phenanthrene in all the tests. Even though high flow was generated in tests using deionized water and 1% HPCD, migration and removal of phenanthrene was low due to low solubility of phenanthrene in these solutions. The test with 10% HPCD solution showed higher solubility of phenanthrene which caused it migrate towards the cathode, but further migration and removal was retarded due to reduced electric current and electroosmotic flow. Approximately one pore volume of flushing resulted in approximately 50% removal of phenanthrene from the soil near the

  9. Removal of heavy metals from emerging cellulosic low-cost adsorbents: a review

    Malik, D. S.; Jain, C. K.; Yadav, Anuj K.

    2016-04-01

    Heavy metal pollution is a major problems in the environment. The impact of toxic metal ions can be minimized by different technologies, viz., chemical precipitation, membrane filtration, oxidation, reverse osmosis, flotation and adsorption. But among them, adsorption was found to be very efficient and common due to the low concentration of metal uptake and economically feasible properties. Cellulosic materials are of low cost and widely used, and very promising for the future. These are available in abundant quantity, are cheap and have low or little economic value. Different forms of cellulosic materials are used as adsorbents such as fibers, leaves, roots, shells, barks, husks, stems and seed as well as other parts also. Natural and modified types of cellulosic materials are used in different metal detoxifications in water and wastewater. In this review paper, the most common and recent materials are reviewed as cellulosic low-cost adsorbents. The elemental properties of cellulosic materials are also discussed along with their cellulose, hemicelluloses and lignin contents.

  10. Removal of heteroatoms and metals from heavy oils by bioconversion processes

    Kaufman, E.N.

    1996-06-01

    Biocatalysts, either appropriate microorganisms or isolated enzymes, will be used in an aqueous phase in contact with the heavy oil phase to extract heteroatoms such as sulfur from the oil phase by bioconversion processes. Somewhat similar work on coal processing will be adapted and extended for this application. Bacteria such as Desulfovibrio desulfuricans will be studied for the reductive removal of organically-bound sulfur and bacteria such as Rhodococcus rhodochrum will be investigated for the oxidative removal of sulfur. Isolated bacteria from either oil field co-produced sour water or from soil contaminated by oil spills will also be tested. At a later time, bacteria that interact with organic nitrogen may also be studied. This type of interaction will be carried out in advanced bioreactor systems where organic and aqueous phases are contacted. One new concept of emulsion-phase contacting, which will be investigated, disperses the aqueous phase in the organic phase and is then recoalesced for removal of the contaminants and recycled back to the reactor. This program is a cooperative research and development program with the following companies: Baker Performance Chemicals, Chevron, Energy BioSystems, Exxon, Texaco, and UNOCAL. After verification of the bioprocessing concepts on a laboratory-scale, the end-product will be a demonstration of the technology at an industrial site. This should result in rapid transfer of the technology to industry.

  11. REMOVAL OF HEAVY METALS FROM DYE EFFLUENT USING ACTIVATED CARBON PRODUCED FROM COCONUT SHELL

    Onyeji, L. I.

    2011-12-01

    Full Text Available The ability of activated carbon produced from coconut shell to remoe mercury Hg (II, Lead Pb (II and Copper Cu (II from dye effluent was investigated. The activated carbon was produced through chemical activation processes by using zinc chloride (ZnCl2. The adsorption capacity was determined as a function of adsorbent dosage. The adsorption Isotherms of the studied metals on adsorbent were also determined and compared with the Langmair models. The activated carbon produced showed excellent effecency in removing Hg (II and Pb(II with percentage removal up to 80 % at low adsorbent dosage of 2 g. In contrast, only about 29 % removal of Cu (II was achieved at adsorbent dosage of 2 g. The study also showed that the adsorption of Hg (II, Pb (II and Cu (II by the activated carbon is dependent on the dosage of the adsorbent and the initial metal concentration. The use of cocnut shell for activated carbon also helps in solving the problem of over abundance of cocnut shell as agricultural waste.

  12. A breakthrough biosorbent in removing heavy metals: Equilibrium, kinetic, thermodynamic and mechanism analyses in a lab-scale study.

    Abdolali, Atefeh; Ngo, Huu Hao; Guo, Wenshan; Lu, Shaoyong; Chen, Shiao-Shing; Nguyen, Nguyen Cong; Zhang, Xinbo; Wang, Jie; Wu, Yun

    2016-01-15

    A breakthrough biosorbent namely multi-metal binding biosorbent (MMBB) made from a combination of tea wastes, maple leaves and mandarin peels, was prepared to evaluate their biosorptive potential for removal of Cd(II), Cu(II), Pb(II) and Zn(II) from multi-metal aqueous solutions. FTIR and SEM were conducted, before and after biosorption, to explore the intensity and position of the available functional groups and changes in adsorbent surface morphology. Carboxylic, hydroxyl and amine groups were found to be the principal functional groups for the sorption of metals. MMBB exhibited best performance at pH 5.5 with maximum sorption capacities of 31.73, 41.06, 76.25 and 26.63 mg/g for Cd(II), Cu(II), Pb(II) and Zn(II), respectively. Pseudo-first and pseudo-second-order models represented the kinetic experimental data in different initial metal concentrations very well. Among two-parameter adsorption isotherm models, the Langmuir equation gave a better fit of the equilibrium data. For Cu(II) and Zn(II), the Khan isotherm describes better biosorption conditions while for Cd(II) and Pb(II), the Sips model was found to provide the best correlation of the biosorption equilibrium data. The calculated thermodynamic parameters indicated feasible, spontaneous and exothermic biosorption process. Overall, this novel MMBB can effectively be utilized as an adsorbent to remove heavy metal ions from aqueous solutions. PMID:26544889

  13. Accumulation of Heavy Metal Ions from Tanneries Wastes: An Approach For Chromium Removal Using Activated Charcoal

    *H. Tahir

    2012-09-01

    Full Text Available The environment is under increasing pressure from solid and liquid wastes emanating from the leather industry. These are inevitable by-products of the leather manufacturing process and causes significant pollution unless treated in some way prior to discharge. The tanneries wastes samples were collected from Lahore Pakistan. The samples were digested by wet oxidation method and the concentrations of metals: Cr, Co, Cu, Cd, Mn, Zn, Ni and Pb were estimated in sediments and liquid waste samples by atomic absorption spectrophotometer. The results show that the concentrations of these metals were higher than the values given by the national environmental quality standards. Selective separation of Cr ion from other metals was investigated in sediment sample TS2 by adsorption method using low cost natural adsorbent activated charcoal. The adsorption studies were carried out under the optimized conditions of adsorption like pH, shaking time and amount of adsorbent. The concentration of Cr after removal was determined by atomic absorption spectrophotometer. The adsorption equilibrium data were fitted in adsorption isotherm equations like: Freundlich, and Dubinin-Radushkevich equations at temperatures ranges from 303 to 318 K. Thermodynamic parameters ∆H, ∆S and ∆G were also calculated. The values of sorption free energy were estimated by employing D-R equation. The percent removal data show that about 99% removal was achieved by employing low cost adsorbent. This method can be employed on industrial scale for the treatment of solid and liquid waste before discharge into the main streams.

  14. Multivariate methods for evaluating the efficiency of electrodialytic removal of heavy metals from polluted harbour sediments

    Pedersen, Kristine Bondo; Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.;

    2015-01-01

    Chemometrics was used to develop a multivariate model based on 46 previously reported electrodialytic remediation experiments (EDR) of five different harbour sediments. The model predicted final concentrations of Cd, Cu, Pb and Zn as a function of current density, remediation time, stirring rate......, dry/wet sediment, cell set-up as well as sediment properties. Evaluation of the model showed that remediation time and current density had the highest comparative influence on the clean-up levels. Individual models for each heavy metal showed variance in the variable importance, indicating that the......-up levels were met in four out of five experiments. The clean-up levels were better than predicted by the model, which could hence be used for predicting an approximate remediation strategy; the modelling power will however improve with more data included. (C) 2014 Elsevier B.V. All rights reserved....

  15. Removal of bisphenol A and some heavy metal ions by polydivinylbenzene magnetic latex particles.

    Marzougui, Zied; Chaabouni, Amel; Elleuch, Boubaker; Elaissari, Abdelhamid

    2016-08-01

    In this study, magnetic polydivinylbenzene latex particles MPDVB with a core-shell structure were tested for the removal of bisphenol A (BPA), copper Cu(II), lead Pb(II), and zinc Zn(II) from aqueous solutions by a batch-adsorption technique. The effect of different parameters, such as initial concentration of pollutant, contact time, adsorbent dose, and initial pH solution on the adsorption of the different adsorbates considered was investigated. The adsorption of BPA, Cu(II), Pb(II), and Zn(II) was found to be fast, and the equilibrium was achieved within 30 min. The pH 5-5.5 was found to be the most suitable pH for metal removal. The presence of electrolytes and their increasing concentration reduced the metal adsorption capacity of the adsorbent. Whereas, the optimal pH for BPA adsorption was found 7, both hydrogen bonds and π-π interaction were thought responsible for the adsorption of BPA on MPDVB. The adsorption kinetics of BPA, Cu(II), Pb(II), and Zn(II) were found to follow a pseudo-second-order kinetic model. Equilibrium data for BPA, Cu(II), Pb(II), and Zn(II) adsorption were fitted well by the Langmuir isotherm model. Furthermore, the desorption and regeneration studies have proven that MPDVB can be employed repeatedly without impacting its adsorption capacity. PMID:26396007

  16. Graft copolymerization of polystyrene onto chitosan congress as an adsorbent for the removal of heavy metal ions

    Chitosan is primarily composed of glucosamine, 2-amino-2-deoxy-β-D-glucose. Chitosan has different types of reactive functional groups. Both hydroxyl and amino groups are possible sites for the reaction to incorporate new and desired functional groups. By modification of these groups various materials for different field of application can be achieved. Chitosan has been used as adsorbent for the removal of heavy metal ions from aqueous solution through adsorption process. Properties of chitosan, such as solubility, mechanical stability and adsorption compatibility, are enhanced by grafting. In this study, chitosan was graft copolymerized with polystyrene for wastewater treatment and evaluated its effectiveness in removing toxic heavy metals by adsorption. Chitosan-graft-polystyrene was characterized by FTIR spectroscopy, and SEM. Adsorption study of the copolymer is carried out as a function of adsorbent dose, pH, and contact time. Residual concentration was measured by Atomic Absorption Spectroscopy. To get an insight of the rate of adsorption and the rate limiting step of the transport mechanism, kinetic analysis was utilized. Langmuir equation/isotherm was used for proper quantification of the sorption equilibrium in the bio sorption process (author)

  17. Novel polyvinylidene fluoride nanofiltration membrane blended with functionalized halloysite nanotubes for dye and heavy metal ions removal.

    Zeng, Guangyong; He, Yi; Zhan, Yingqing; Zhang, Lei; Pan, Yang; Zhang, Chunli; Yu, Zongxue

    2016-11-01

    Membrane separation is an effective method for the removal of hazardous materials from wastewater. Halloysite nanotubes (HNTs) were functionalized with 3-aminopropyltriethoxysilane (APTES), and novel polyvinylidene fluoride (PVDF) nanofiltration membranes were prepared by blending with various concentrations of APTES grafted HNTs (A-HNTs). The morphology structure of the membranes were characterized by scanning electron microscope (SEM) and atomic force microscopy (AFM). The contact angle (CA), pure water flux (PWF) and antifouling capacity of membranes were investigated in detail. In addition, the separation performance of membranes were reflected by the removal of dye and heavy metal ions in simulated wastewater. The results revealed that the hydrophilicity of A-HNTs blended PVDF membrane (A-HNTs@PVDF) was enhanced significantly. Owing to the electrostatic interaction between membrane surface and dye molecules, the dye rejection ratio of 3% A-HNTs@PVDF membrane reached 94.9%. The heavy metal ions rejection ratio and adsorption capacity of membrane were also improved with the addition of A-HNTs. More importantly, A-HNTs@PVDF membrane exhibited excellent rejection stability and reuse performances after several times fouling and washing tests. It can be expected that the present work will provide insight into a new method for membrane modification in the field of wastewater treatment. PMID:27262273

  18. Removal of heavy metals from wastewater using CFB-coal fly ash zeolitic materials

    Polish bituminous (PB) and South African (SA) coal fly ash (FA) samples, derived from pilot-scale circulated fluidized bed (CFB) combustion facilities, were utilized as raw materials for the synthesis of zeolitic products. The two FAs underwent a hydrothermal activation with 1 M NaOH solution. Two different FA/NaOH solution/ratios (50, 100 g/L) were applied for each sample and several zeolitic materials were formed. The experimental products were characterized by means of X-ray diffraction (XRD) and energy dispersive X-ray coupled-scanning electron microscope (EDX/SEM), while X-ray fluorescence (XRF) was applied for the determination of their chemical composition. The zeolitic products were also evaluated in terms of their cation exchange capacity (CEC), specific surface area (SSA), specific gravity (SG), particle size distribution (PSD), pH and the range of their micro- and macroporosity. Afterwards the hybrid materials were tested for their ability of adsorbing Cr, Pb, Ni, Cu, Cd and Zn from contaminated liquids. Main parameters for the precipitation of the heavy metals, as it was concluded from the experimental results, are the mineralogical composition of the initial fly ashes, as well as the type and the amount of the produced zeolite and specifically the mechanism by which the metals ions are hold on the substrate.

  19. An intelligent displacement pumping film system: A new concept for enhancing heavy metal ion removal efficiency from liquid waste

    Highlights: • A new concept for design of an intelligent displacement pumping film was proposed. • As-prepared ESIX hybrid film system showed excellent Ni2+ uptake/exclude rate. • Piston-like proton pumping effect existed in the prepared ESIX hybrid film. • The mechanism of the ion pumping effect was proved by XPS analysis. - Abstract: A concept of electrochemically switched ion exchange (ESIX) hybrid film system with piston-like proton pumping effect for the removal of heavy metal ions was proposed. Based on this concept, a novel ESIX hybrid film composed of layered alpha zirconium phosphate (α-Zr(HPO4)2; α-ZrP) nanosheets intercalated with a potential-responsive conducting polyaniline (PANI) was developed for the removal of Ni2+ ions from wastewater. It is expected that the space between α-ZrP nanosheets acts as the reservoir for the functional ions while the intercalated PANI works as the potential-sensitive function element for piston-like proton pumping in such ESIX hybrid films. The prepared ESIX hybrid film showed an excellent property of rapid removal of Ni2+ ions from wastewater with a high selectivity. The used film was simply regenerated by only altering the applied potential. The ion pumping effect for the ESIX of Ni2+ ions using this kind of film was proved via XPS analysis. The proposed ESIX hybrid film should have high potential for the removal of Ni2+ ions and/or other heavy metal ions from wastewater in various industrial processes

  20. Effects of Humic Acid and Suspended Solids on the Removal of Heavy Metals from Water by Adsorption onto Granular Activated Carbon

    Danious P. Sounthararajah

    2015-08-01

    Full Text Available Heavy metals constitute some of the most dangerous pollutants of water, as they are toxic to humans, animals, and aquatic organisms. These metals are considered to be of major public health concern and, therefore, need to be removed. Adsorption is a common physico-chemical process used to remove heavy metals. Dissolved organic carbon (DOC and suspended solids (SS are associated pollutants in water systems that can interact with heavy metals during the treatment process. The interactions of DOC and SS during the removal of heavy metals by granular activated carbon were investigated in batch and fixed-bed column experiments. Batch adsorption studies indicated that Langmuir adsorption maxima for Pb, Cu, Zn, Cd, and Ni at pH 6.5 were 11.9, 11.8, 3.3, 2.0, and 1.8 mg/g, respectively. With the addition of humic acid (HA (DOC representative, they were 7.5, 3.7, 3.2, 1.6, and 2.5 mg/g, respectively. In the column experiment, no breakthrough (complete removal was obtained for Pb and Cu, but adding HA provided a breakthrough in removing these metals. For Zn, Cd and Ni, this breakthrough occurred even without HA being added. Adding kaolinite (representative of SS had no effect on Pb and Cu, but it did on the other metals.

  1. Removal of heavy metals from aqueous solutions using Fe3O4, ZnO, and CuO nanoparticles

    This study investigated the removal of Cd2+, Cu2+, Ni2+, and Pb2+ from aqueous solutions with novel nanoparticle sorbents (Fe3O4, ZnO, and CuO) using a range of experimental approaches, including, pH, competing ions, sorbent masses, contact time, scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The images showed that Fe3O4, ZnO, and CuO particles had mean diameters of about 50 nm (spheroid), 25 nm (rod shape), and 75 nm (spheroid), respectively. Tests were performed under batch conditions to determine the adsorption rate and uptake at equilibrium from single and multiple component solutions. The maximum uptake values (sum of four metals) in multiple component solutions were 360.6, 114.5, and 73.0 mg g−1, for ZnO, CuO, and Fe3O4, respectively. Based on the average metal removal by the three nanoparticles, the following order was determined for single component solutions: Cd2+ > Pb2+ > Cu2+ > Ni2+, while the following order was determined in multiple component solutions: Pb2+ > Cu2+ > Cd2+ > Ni2+. Sorption equilibrium isotherms could be described using the Freundlich model in some cases, whereas other isotherms did not follow this model. Furthermore, a pseudo-second order kinetic model was found to correctly describe the experimental data for all nanoparticles. Scanning electron microscopy, energy dispersive X-ray before and after metal sorption, and soil solution saturation indices showed that the main mechanism of sorption for Cd2+ and Pb2+ was adsorption, whereas both Cu2+ and Ni2+ sorption were due to adsorption and precipitation. These nanoparticles have potential for use as efficient sorbents for the removal of heavy metals from aqueous solutions and ZnO nanoparticles were identified as the most promising sorbent due to their high metal uptake.

  2. Application of the artificial intelligence to estimate the constructed wetland response to heavy metal removal

    Current design approaches lack essential parameters necessary to evaluate the removal of metals contained in wastewater which is discharged to constructed wetlands. As a result, there is no guideline for an accurate design of constructed wetlands. An artificial intelligence approach was used to assess constructed wetland design. For this purpose concentrations of bioavailable mercury were evaluated in conditions where initial concentrations of inorganic mercury, chloride concentrations and pH values changed. Fuzzy knowledge base was built based on results obtained from previous investigations performed in a greenhouse for floating plants, and from computations for mercury speciation. The Fuzzy Decision Support System (FDSS) used the knowledge base to find parameters that permit to generate the highest amount of mercury available for plants. The findings of this research can be applied to wetlands and all natural processes where correlations between them are uncertain. (author)

  3. Preparation and characterization of bentonite clays mixture destined to the removal of heavy metals

    In this work a mixture was prepared with 50% wt. of the Bofe and Verde-lodo clays. The characterization methods used they were: thermal analyses (TG and DTG), X-ray diffraction, fisissorption of N2, scanning electron microscopy and X-ray energy dispersive spectroscopy. The rehearsals of adsorption we accomplished in system of finite bath using as adsorbent the mixture loamy in natura or it mixes calcined. Starting from TG and DTG a thermal treatment was accomplished to 500 deg C of the loamy mixture. Through the results of the copper adsorption, it was verified that mixes loamy it provokes chemical precipitation of the copper while the calcined sample presents amount metal adsorbed around 7.31 mg of copper/g of adsorbent. The value of removal percentage obtained by the calcined sample it was of 63.02%. (author)

  4. Adsorptive removal of heavy metals from aqueous solution by treated sawdust (Acacia arabica)

    Meena, Ajay Kumar [Centre for Fire, Explosive and Environment Safety (CFEES), Defence R and D Organisation (DRDO), Brig. S.K. Mazumdar Road, Timarpur, Delhi 110054 (India); Kadirvelu, K. [Centre for Fire, Explosive and Environment Safety (CFEES), Defence R and D Organisation (DRDO), Brig. S.K. Mazumdar Road, Timarpur, Delhi 110054 (India)], E-mail: kadirvelu@lycos.com; Mishra, G.K.; Rajagopal, Chitra [Centre for Fire, Explosive and Environment Safety (CFEES), Defence R and D Organisation (DRDO), Brig. S.K. Mazumdar Road, Timarpur, Delhi 110054 (India); Nagar, P.N. [Centre for Fire, Explosive and Environment Safety (CFEES), Defence R and D Organisation (DRDO), Brig. S.K. Mazumdar Road, Timarpur, Delhi 110054 (India); Department of Chemistry, University of Rajasthan, Jaipur 302004 (India)

    2008-02-11

    The removal of Cr(VI), Pb(II), Hg(II) and Cu(II), by treated sawdust has been found to be concentration, pH, contact time, adsorbent dose and temperature dependent. The adsorption parameters were determined using both Langmuir and Freundlich isotherm models. Adsorption capacity for treated sawdust, i.e. Cr(VI) (111.61 mg/g), Pb(II) (52.38 mg/g), Hg(II) (20.62 mg/g), and Cu(II) (5.64 mg/g), respectively. Surface complexation and ion exchange are the major removal mechanisms involved. The adsorption isotherm studies clearly indicated that the adsorptive behaviour of metal ions on treated sawdust satisfies not only the Langmuir assumptions but also the Freundlich assumptions. The applicability of Lagergren kinetic model has also been investigated. The adsorption follows first-order kinetics. Thermodynamic constant (k{sub ad}), standard free energy ({delta}G{sup o}), enthalpy ({delta}H{sup o}) and entropy ({delta}S{sup o}) were calculated for predicting the nature of adsorption. The percentage adsorption increases with pH to attain a maximum at pH 6 and thereafter it decreases with further increase in pH. The results indicate the potential application of this method for effluent treatment in industries and also provide strong evidence to support the adsorption mechanism proposed.

  5. Adsorptive removal of heavy metals from aqueous solution by treated sawdust (Acacia arabica)

    The removal of Cr(VI), Pb(II), Hg(II) and Cu(II), by treated sawdust has been found to be concentration, pH, contact time, adsorbent dose and temperature dependent. The adsorption parameters were determined using both Langmuir and Freundlich isotherm models. Adsorption capacity for treated sawdust, i.e. Cr(VI) (111.61 mg/g), Pb(II) (52.38 mg/g), Hg(II) (20.62 mg/g), and Cu(II) (5.64 mg/g), respectively. Surface complexation and ion exchange are the major removal mechanisms involved. The adsorption isotherm studies clearly indicated that the adsorptive behaviour of metal ions on treated sawdust satisfies not only the Langmuir assumptions but also the Freundlich assumptions. The applicability of Lagergren kinetic model has also been investigated. The adsorption follows first-order kinetics. Thermodynamic constant (kad), standard free energy (ΔGo), enthalpy (ΔHo) and entropy (ΔSo) were calculated for predicting the nature of adsorption. The percentage adsorption increases with pH to attain a maximum at pH 6 and thereafter it decreases with further increase in pH. The results indicate the potential application of this method for effluent treatment in industries and also provide strong evidence to support the adsorption mechanism proposed

  6. Heavy metal removal from produced water using retorted shale; Remocao de metais pesados em aguas produzidas utilizando xisto retortado

    Pimentel, Patricia M.; Melo, Marcos A.F.; Melo, Dulce M.A.; Silva Junior, Carlos N.; Assuncao, Ary L.C. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Anjos, Marcelino J. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia

    2004-07-01

    The Production of oil and gas is usually accompanied by the production of large volume of water that can have significant environmental effects if not properly treated. In this work, the use of retort shale was investigated as adsorbent agent to remove heavy metals in produced water. Batch adsorption studies in synthetic solution were performed for several metal ions. The efficiency removal was controlled by solution pH, adsorbent dosage, and initial ion concentration and agitation times. Two simple kinetic models were used, pseudo-first- and second-order, were tested to investigate the adsorption mechanisms. The equilibrium data fitted well with Langmuir and Freundlich models. The produced water samples were treated by retorted shale under optimum adsorption conditions. Synchrotron radiation total reflection X-ray fluorescence was used to analyze the elements present in produced water samples from oil field in Rio Grande do Norte, Brazil. The removal was found to be approximately 20-50% for Co, Ni, Sr and above 80% for Cr, Ba, Hg and Pb. (author)

  7. Adsorptive removal of heavy metal ions from industrial effluents using activated carbon derived from waste coconut buttons.

    Anirudhan, T S; Sreekumari, S S

    2011-01-01

    Activated carbon (AC) derived from waste coconut buttons (CB) was investigated as a suitable adsorbent for the removal of heavy metal ions such as Pb(II), Hg(II) and Cu(II) from industrial effluents through batch adsorption process. The AC was characterized by elemental analysis, fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, thermal gravimetric and differential thermal analysis, surface area analyzer and potentiometric titrations. The effects of initial metal concentration, contact time, pH and adsorbent dose on the adsorption of metal ions were studied. The adsorbent revealed a good adsorption potential for Pb(II) and Cu(II) at pH 6.0 and for Hg(II) at pH 7.0. The experimental kinetic data were a better fit with pseudo second-order equation rather than pseudo first-order equation. The Freundlich isotherm model was found to be more suitable to represent the experimental equilibrium isotherm results for the three metals than the Langmuir model. The adsorption capacities of the AC decreased in the order: Pb(II) > Hg(II) > Cu(II). PMID:22432329

  8. Adsorptive removal of heavy metal ions from industrial effluents using activated carbon derived from waste coconut buttons

    T. S. Anirudhan; S. S. Sreekumari

    2011-01-01

    Activated carbon (AC) derived from waste coconut buttons (CB) was investigated as a suitable adsorbent for the removal of heavy metal ions such as Pb(Ⅱ),Hg(Ⅱ) and Cu(Ⅱ) from industrial effluents through batch adsorption process.The AC was characterized by elemental analysis,fourier transform infrared spectroscopy,X-ray diffraction,scanning electron microscopy,thermal gravimetric and differential thermal analysis,surface area analyzer and potentiometric titrations.The effects of initial metal concentration,contact time,pH and adsorbent dose on the adsorption of metal ions were studied.The adsorbent revealed a good adsorption potential for Pb(Ⅱ) and Cu(Ⅱ) at pH 6.0 and for Hg(Ⅱ) at pH 7.0.The experimental kinetic data were a better fit with pseudo second-order equation rather than pseudo first-order equation.The Freundlich isotherm model was found to be more suitable to represent the experimental equilibrium isotherm results for the three metals than the Langmuir model.The adsorption capacities of the AC decreased in the order:Pb(Ⅱ) >Hg(Ⅱ) > Cu(Ⅱ).

  9. Electrodialytic treatment of municipal wastewater and sludge for the removal of heavy metals and recovery of phosphorus

    Ebbers, Benjamin; Ottosen, Lisbeth M.; Jensen, Pernille Erland

    2015-01-01

    Municipal wastewater and sewage sludge is an abundant source of phosphorus (P), but its usage is often limited due to wastewater treatment methods and contaminants, mostly heavy metals (HM's). Three compartment (3C) electrodialysis (ED) was used to simultaneously extract HM's (Cd, Cr, Cu, Ni, Pb...... and Zn) and recover P from municipal sludge samples obtained at different stages during wastewater treatment involving biological and chemical treatment as well as polymer addition for thickening of sludge and anaerobic digestion of excess sludge. Direct P recovery was investigated for high P reject...... concentration P streams was most effective using a 3C ED cell setup, with the electrodes separated from the sample by ion-exchange membranes. Extraction with the 2C ED cell setup was less effective due to a rise in pH, caused by half reactions at the cathode and subsequent precipitation of P. For either removal...

  10. Chitosan and reinforced Chitosan films for the removal of Cr(VI heavy metal from synthetic aqueous solution

    Sibi Srinivasan

    2016-05-01

    Full Text Available Cr(VI is removed efficiently from aqueous solution using Chitosan made films as the adsorbent. The efficiency of free Chitosan films is compared with the Chitosan-Silica and Chitosan-Carbon, which are reinforced with biogenic Silica and Carbon obtained from Panicum miliare husk ashes, respectively. All the films were prepared by simple ageing method and swelling index was determined for all the three adsorbents independently. Adsorption studies of Cr(VI heavy metal were carried out by varying pH, temperature, initial concentration of the adsorbate and quantity of adsorbent. On the otherhand, Cr(VI was removed from the solution by Chitosan-Silica film better than free Chitosan and Chitosan-Carbon films. The optimum pH was found to be 3.0 and optimum temperature was 30°C. Thermodynamic, equilibrium and kinetic studies were carried out for all the three adsorbents, independently. Langmuir adsorption isotherm and Pseudo First Order kinetics were followed for the adsorption process. Concentration of metal ions was determined using a spectrophotometer. Oxidation states of the adsorbed Cr were determined by ESR. It was found that Chitosan-Silica film reduced Cr(VI to Cr(III almost completely in the aqueous solution.

  11. Coupled electrokinetics-adsorption technique for simultaneous removal of heavy metals and organics from saline-sodic soil.

    Lukman, Salihu; Essa, Mohammed Hussain; Mu'azu, Nuhu Dalhat; Bukhari, Alaadin

    2013-01-01

    In situ remediation technologies for contaminated soils are faced with significant technical challenges when the contaminated soil has low permeability. Popular traditional technologies are rendered ineffective due to the difficulty encountered in accessing the contaminants as well as when employed in settings where the soil contains mixed contaminants such as petroleum hydrocarbons, heavy metals, and polar organics. In this study, an integrated in situ remediation technique that couples electrokinetics with adsorption, using locally produced granular activated carbon from date palm pits in the treatment zones that are installed directly to bracket the contaminated soils at bench-scale, is investigated. Natural saline-sodic soil, spiked with contaminant mixture (kerosene, phenol, Cr, Cd, Cu, Zn, Pb, and Hg), was used in this study to investigate the efficiency of contaminant removal. For the 21-day period of continuous electrokinetics-adsorption experimental run, efficiency for the removal of Zn, Pb, Cu, Cd, Cr, Hg, phenol, and kerosene was found to reach 26.8, 55.8, 41.0, 34.4, 75.9, 92.49, 100.0, and 49.8%, respectively. The results obtained suggest that integrating adsorption into electrokinetic technology is a promising solution for removal of contaminant mixture from saline-sodic soils. PMID:24235885

  12. Coupled Electrokinetics-Adsorption Technique for Simultaneous Removal of Heavy Metals and Organics from Saline-Sodic Soil

    Salihu Lukman

    2013-01-01

    Full Text Available In situ remediation technologies for contaminated soils are faced with significant technical challenges when the contaminated soil has low permeability. Popular traditional technologies are rendered ineffective due to the difficulty encountered in accessing the contaminants as well as when employed in settings where the soil contains mixed contaminants such as petroleum hydrocarbons, heavy metals, and polar organics. In this study, an integrated in situ remediation technique that couples electrokinetics with adsorption, using locally produced granular activated carbon from date palm pits in the treatment zones that are installed directly to bracket the contaminated soils at bench-scale, is investigated. Natural saline-sodic soil, spiked with contaminant mixture (kerosene, phenol, Cr, Cd, Cu, Zn, Pb, and Hg, was used in this study to investigate the efficiency of contaminant removal. For the 21-day period of continuous electrokinetics-adsorption experimental run, efficiency for the removal of Zn, Pb, Cu, Cd, Cr, Hg, phenol, and kerosene was found to reach 26.8, 55.8, 41.0, 34.4, 75.9, 92.49, 100.0, and 49.8%, respectively. The results obtained suggest that integrating adsorption into electrokinetic technology is a promising solution for removal of contaminant mixture from saline-sodic soils.

  13. Impact of carbonate on the efficiency of heavy metal removal from kaolinite soil by the electrokinetic soil remediation method.

    Ouhadi, V R; Yong, R N; Shariatmadari, N; Saeidijam, S; Goodarzi, A R; Safari-Zanjani, M

    2010-01-15

    While the feasibility of using electrokinetics to decontaminate soils has been studied by several authors, the effects of soil composition on the efficiency of this method of decontamination has yet to be fully studied. This study focuses its attention on the effect of "calcite or carbonate" (CaCO(3)) on removal efficiency in electrokinetic soil remediation. Bench scale experiments were conducted on two soils: kaolinite and natural-soil of a landfill in Hamedan, Iran. Prescribed quantities of carbonates were mixed with these soils which were subsequently contaminated with zinc nitrate. After that, electrokinetic experiments were conducted to determine the efficiency of electrokinetic remediation. The results showed that an increase in the quantity of carbonate caused a noticeable increase on the contaminant retention of soil and on the resistance of soil to the contaminant removal by electrokinetic method. Because the presence of carbonates in the soil increases its buffering capacity, acidification is reduced, resulting in a decrease in the rate of heavy metal removed from the contaminant soil. This conclusion was validated by the evaluation of efficiency of electrokinetic method on a soil sample from the liner of a waste disposal site, with 28% carbonates. PMID:19733966

  14. Impact of carbonate on the efficiency of heavy metal removal from kaolinite soil by the electrokinetic soil remediation method

    Ouhadi, V.R., E-mail: vahidouhadi@yahoo.ca [Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of); Yong, R.N. [RNY Geoenvironmental Research, North Saanich (Canada); Shariatmadari, N. [Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Saeidijam, S.; Goodarzi, A.R.; Safari-Zanjani, M. [Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of)

    2010-01-15

    While the feasibility of using electrokinetics to decontaminate soils has been studied by several authors, the effects of soil composition on the efficiency of this method of decontamination has yet to be fully studied. This study focuses its attention on the effect of 'calcite or carbonate' (CaCO{sub 3}) on removal efficiency in electrokinetic soil remediation. Bench scale experiments were conducted on two soils: kaolinite and natural-soil of a landfill in Hamedan, Iran. Prescribed quantities of carbonates were mixed with these soils which were subsequently contaminated with zinc nitrate. After that, electrokinetic experiments were conducted to determine the efficiency of electrokinetic remediation. The results showed that an increase in the quantity of carbonate caused a noticeable increase on the contaminant retention of soil and on the resistance of soil to the contaminant removal by electrokinetic method. Because the presence of carbonates in the soil increases its buffering capacity, acidification is reduced, resulting in a decrease in the rate of heavy metal removed from the contaminant soil. This conclusion was validated by the evaluation of efficiency of electrokinetic method on a soil sample from the liner of a waste disposal site, with 28% carbonates.

  15. Highly effective removal of heavy metals by polymer-based zirconium phosphate: a case study of lead ion.

    Pan, B C; Zhang, Q R; Zhang, W M; Pan, B J; Du, W; Lv, L; Zhang, Q J; Xu, Z W; Zhang, Q X

    2007-06-01

    Zirconium phosphate (ZrP) has recently been demonstrated as an excellent sorbent for heavy metals due to its high selectivity, high thermal stability, and absolute insolubility in water. However, it cannot be readily adopted in fixed beds or any other flowthrough system due to the excessive pressure drop and poor mechanical strength resulting from its fine submicrometer particle sizes. In the present study a hybrid sorbent, i.e., polymer-supported ZrP, was prepared by dispersing ZrP within a strongly acidic cation exchanger D-001 and used for enhanced lead removal from contaminated waters. D-001 was selected as a host material for sorbent preparation mainly because of the Donnan membrane effect resulting from the nondiffusible negatively charged sulfonic acid group on the exchanger surface, which would enhance permeation of the targeted metal ions. The hybrid sorbent (hereafter denoted ZrP-001) was characterized using a nitrogen adsorption technique, scanning electron microscope (SEM), and X-ray diffraction (XRD). Lead sorption onto ZrP-001 was found to be pH dependent due to the ion-exchange mechanism, and its sorption kinetics onto ZrP-001 followed the pseudo-first-order model. Compared to D-001, ZrP-001 exhibited more favorable lead sorption particularly in terms of high selectivity, as indicated by its substantially larger distribution coefficients when other competing cations Na(+), Ca(2+), and Mg(2+) coexisted at a high level in solution. Fixed-bed column runs showed that lead sorption on ZrP-001 resulted in a conspicuous decrease of this toxic metal from 40 mg/L to below 0.05 mg/L. By comparison with D-001 and ZrP-CP (ZrP dispersion within a neutrally charged polymer CP), enhanced removal efficiency of ZrP-001 resulted from the Donnan membrane effect of the host material D-001. Moreover, its feasible regeneration by diluted acid solution and negligible ZrP loss during operation also helps ZrP-001 to be a potential candidate for lead removal from water. Thus

  16. Effect of different surfactants on removal efficiency of heavy metals in sewage sludge treated by a novel method combining bio-acidification with Fenton oxidation

    任苗苗; 林宁波; 袁兴中; 朱艺; 黄华军; 曾光明; 李辉; 陈明; 王侯; 陈畅亚

    2014-01-01

    The aim of this work was to investigate the effect of different surfactants on the removal efficiency of heavy metals in sewage sludge treated by a method combining bio-acidification with Fenton oxidation. Four surfactants were adopted such as anionic surfactant (sodium dodecyl benzene sulfonate, SDBS), nonionic surfactants (tween-20 and tween-60) and cationic surfactant (hexadecyl trimethyl ammonium chloride, HTAC), respectively. The indigenous sulfur-oxidizing bacteria in bio-acidification phase were enriched and cultured from fresh activated sludge obtained from a wastewater treatment plant. It is shown that different surfactants exhibited distinct effect on the removal efficiency of heavy metals from sewage sludge. The nonionic surfactants, especially tween-60, promotes the solubilization of heavy metals, while the anionic and cationic surfactants hinder the removal of heavy metals. Copper is efficiently leached. The removal efficiency of cadium is relatively lower than that of Cu due to the demand for rigorous pH value. Lead is leached with a low efficiency as the formation of low soluble PbSO4 precipitates.

  17. OPTIMIZATION OF MOTOR VEHICLE INDUSTRIES WASTEWATER TREATMENT METHODS WITH THE AIM OF HEAVY METALS REMOVAL AND WATER REUSE IN PILOT SCALE

    S. A. Mirbagheri, M. Salehi M

    2006-10-01

    Full Text Available The waste of motor vehicle industries is mainly the result of washing, coloring and various stages of chassis manufacturing, which include oil, grease, dyestuff, chromium, phosphate and other pollutants. In the present research, extended aeration activated sludge biological treatment plant is being considered and evaluated, for the removal of heavy metals and pollution load from industrial wastes and sanitary wastewaters, and on the pilot scale for optimization of waste treatment method for motor vehicle industries. To accomplish the pilot experiments, the natural waste of Bahman motor vehicle factory is used. Effective factors on efficient removal of heavy metals and pollution load such as concentration of biological mass (MLVSS, COD, BOD, pH in the extended aeration activated sludge biological treatment system, in different ratios of the mixing of industrial waste to sanitary wastewater have been experimented and evaluated. The performance of the above system, in the best of conditions, removes about 90% of pollution load and 65% of heavy metals existing in the industrial wastes. After analyzing the experiments, it is concluded that the removal of heavy metals through biological methods is possible and moreover it is feasible to biologically treat the mixing of motor vehicle industries effluent and sanitary wastewater up to the ratio of one to one, if guided exactly and scientifically.

  18. Removal of selected heavy metals from MSW fly ash by the electrodialytic process

    Ferreira, Célia Maria Dias; Jensen, Pernille Erland; Ottosen, Lisbeth M.;

    2005-01-01

    This paper aims to assess the applicability of the electrodialytic remediation technique for the removal of zinc, lead, copper and cadmium from municipal solid waste (MSW) incinerator fly ash. A broad range of experimental conditions were studied including current densities, remediation times, use...

  19. Perspectives of phytoremediation using water hyacinth for removal of heavy metals, organic and inorganic pollutants in wastewater.

    Rezania, Shahabaldin; Ponraj, Mohanadoss; Talaiekhozani, Amirreza; Mohamad, Shaza Eva; Md Din, Mohd Fadhil; Taib, Shazwin Mat; Sabbagh, Farzaneh; Sairan, Fadzlin Md

    2015-11-01

    The development of eco-friendly and efficient technologies for treating wastewater is one of the attractive research area. Phytoremediation is considered to be a possible method for the removal of pollutants present in wastewater and recognized as a better green remediation technology. Nowadays the focus is to look for a sustainable approach in developing wastewater treatment capability. Water hyacinth is one of the ancient technology that has been still used in the modern era. Although, many papers in relation to wastewater treatment using water hyacinth have been published, recently removal of organic, inorganic and heavy metal have not been reviewed extensively. The main objective of this paper is to review the possibility of using water hyacinth for the removal of pollutants present in different types of wastewater. Water hyacinth is although reported to be as one of the most problematic plants worldwide due to its uncontrollable growth in water bodies but its quest for nutrient absorption has provided way for its usage in phytoremediation, along with the combination of herbicidal control, integratated biological control and watershed management controlling nutrient supply to control its growth. Moreover as a part of solving wastewater treatment problems in urban or industrial areas using this plant, a large number of useful byproducts can be developed like animal and fish feed, power plant energy (briquette), ethanol, biogas, composting and fiber board making. In focus to the future aspects of phytoremediation, the utilization of invasive plants in pollution abatement phytotechnologies can certainly assist for their sustainable management in treating waste water. PMID:26311085

  20. Removal of organic pollutants and heavy metals in soils by electrokinetic remediation.

    Ricart, M T; Pazos, M; Gouveia, S; Cameselle, C; Sanroman, M A

    2008-07-01

    In this work, the feasibility of electrokinetic remediation for the restoration of polluted soil with organic and inorganic compounds had been development and evaluated using a model soil sample. The model soil was prepared with kaolinite clay artificially polluted in the laboratory with chromium and an azo dye: Reactive Black 5 (RB5). The electromigration of Cr in a spiked kaolinite sample was studied in alkaline conditions. Despite of the high pH registered in the kaolinite sample (around pH 9.5), Cr migrated towards the cathode and it was accumulated in the cathode chamber forming a white precipitate. The removal was not complete, and 23% of the initial Cr was retained into the kaolinite sample close to the cathode side. The azo dye RB5 could be effectively removed from kaolinite by electrokinetics and the complete cleanup of the kaolinite could be achieved in alkaline environment. In this condition, RB5 formed an anion that migrated towards the anode where it was accumulated and quickly degraded upon the electrode surface. The electrokinetic treatment of a kaolinite sample polluted with both Cr and RB5 yielded very good results. The removal of Cr was improved compared to the experiment where Cr was the only pollutant, and RB5 reached a removal as high as 95%. RB5 was removed by electromigration towards the anode, where the dye was degraded upon the surface of the electrode by electrochemical oxidation. Cr was transported towards the cathode by electromigration and electroosmosis. It is supposed that the interaction among RB5 and Cr into the kaolinite sample prevented premature precipitation and allow Cr to migrate and concentrate in the cathode chamber. PMID:18569297

  1. 用细菌运河除水中的重金属%Removal of Heavy Metals from Aqueous Solutions Using Bacteria

    黄民生; 潘静; 郑乐平

    2001-01-01

    The accumulation of heavy metals by microbial biomass with high surface area-to-volume ratio holds great potential for heavy metal removal in both soluble and paritcular forms, especially when the heavy metal concentrations are low (< 50 mg/L). E. coli and B. subtilis are effective agents for metal removal. We further investigated the effect of pH, temperature, equilibration time, and pre-treatment reagents on the removal of Pb( Ⅱ ), Cd( Ⅱ ) and Cr( Ⅵ ) from aqueous solutions by E. coli and B. subtilis. E. coli and B. subtilis were cultivated for 60 hours, the experimentally determined optimal cultivation time before they were used in metal removal experiments. Under the optimal conditions of pH 6.0, equilibration temperature 30 ℃ and equilibration time 1 hour, 63.39 % and 69.90 % Cd( Ⅱ ) can be removed by E. coli and B. subtilis. Under the optimal conditions of pH 5.5, equilibration temperature 30 ℃ and equilibration time 1 hour, 68.51% and 67.36% Pb( Ⅱ ) can be removed by E. coli and B. subtilis. And under the optimal conditions of pH 5.5, equilibration temperature 30 ℃, and equilibration time 1 hour, 60.26% and 54.56% Cr( Ⅵ ) can be removed by E. coli and B. subtilis. Chemical treatment of cultivated bacteria (0.1 mol/L NaOH, 0.1 mol/L, HCl, 30% ethanol, and distilled water) affects the efficiency of metal removal by E. coli and B. subtilis. Pretreatment of biomass by NaOH enhanced Cd( Ⅱ ), Pb( Ⅱ ) and Cr( Ⅵ ) removal, while pretreatment by HCl, ethanol and distilled water reduced Cd( Ⅱ ), Pb( Ⅱ ) and Ct( Ⅵ ) removal. For metal removal from industrial waste discharges, pretreated biomass of E. coli can remove 68.5 % of Cd and 58.1% of Cr from solutions, while pretreated biomass of B. subtilis can remove 62.6% of Cd and 57% of Cr from solutions.

  2. Arsenic removal via electrocoagulation from heavy metal contaminated groundwater in La Comarca Lagunera Mexico

    Arsenic contamination is an enormous worldwide problem. A large number of people dwelling in Comarca Lagunera, situated in the central part of northern Mexico, use well water with arsenic in excess of the water standard regulated by the Secretary of Environment and Natural Resources of Mexico (SEMARNAT), to be suitable for human health. Individuals with lifetime exposure to arsenic develop the classic symptoms of arsenic poisoning. Among several options available for removal of arsenic from well water, electrocoagulation (EC) is a very promising electrochemical treatment technique that does not require the addition of chemicals or regeneration. First, this study will provide an introduction to the fundamental concepts of the EC method. In this study, powder X-ray diffraction, scanning electron microscopy, transmission Moessbauer spectroscopy and Fourier transform infrared spectroscopy were used to characterize the solid products formed at iron electrodes during the EC process. The results suggest that magnetite particles and amorphous iron oxyhydroxides present in the EC products remove arsenic(III) and arsenic(V) with an efficiency of more than 99% from groundwater in a field pilot scale study

  3. Arsenic removal via electrocoagulation from heavy metal contaminated groundwater in La Comarca Lagunera Mexico

    Parga, Jose R. [Institute Technology of Saltillo, Department of Metallurgy and Materials Science, V. Carranza 2400, C.P. 25280, Saltillo, Coahuila, Mexico (Mexico)]. E-mail: drjrparga@hotmail.com; Cocke, David L. [Lamar University, Gill Chair of Chemistry and Chemical Engineering, Beaumont, TX 77710 (United States); Valenzuela, Jesus L. [University of Sonora, Hermosillo, Sonora, Mexico (Mexico); Gomes, Jewel A. [Lamar University, Gill Chair of Chemistry and Chemical Engineering, Beaumont, TX 77710 (United States); Kesmez, Mehmet [Lamar University, Gill Chair of Chemistry and Chemical Engineering, Beaumont, TX 77710 (United States); Irwin, George [Lamar University, Department of Chemistry and Physics, Beaumont, TX 77710 (United States); Moreno, Hector [Lamar University, Gill Chair of Chemistry and Chemical Engineering, Beaumont, TX 77710 (United States); Weir, Michael [Lamar University, Gill Chair of Chemistry and Chemical Engineering, Beaumont, TX 77710 (United States)

    2005-09-30

    Arsenic contamination is an enormous worldwide problem. A large number of people dwelling in Comarca Lagunera, situated in the central part of northern Mexico, use well water with arsenic in excess of the water standard regulated by the Secretary of Environment and Natural Resources of Mexico (SEMARNAT), to be suitable for human health. Individuals with lifetime exposure to arsenic develop the classic symptoms of arsenic poisoning. Among several options available for removal of arsenic from well water, electrocoagulation (EC) is a very promising electrochemical treatment technique that does not require the addition of chemicals or regeneration. First, this study will provide an introduction to the fundamental concepts of the EC method. In this study, powder X-ray diffraction, scanning electron microscopy, transmission Moessbauer spectroscopy and Fourier transform infrared spectroscopy were used to characterize the solid products formed at iron electrodes during the EC process. The results suggest that magnetite particles and amorphous iron oxyhydroxides present in the EC products remove arsenic(III) and arsenic(V) with an efficiency of more than 99% from groundwater in a field pilot scale study.

  4. Organic-Inorganic Hybrid Polymers as Adsorbents for Removal of Heavy Metal Ions from Solutions: A Review

    Babak Samiey

    2014-01-01

    Full Text Available Over the past decades, organic-inorganic hybrid polymers have been applied in different fields, including the adsorption of pollutants from wastewater and solid-state separations. In this review, firstly, these compounds are classified. These compounds are prepared by sol-gel method, self-assembly process (mesopores, assembling of nanobuilding blocks (e.g., layered or core-shell compounds and as interpenetrating networks and hierarchically structures. Lastly, the adsorption characteristics of heavy metals of these materials, including different kinds of functional groups, selectivity of them for heavy metals, effect of pH and synthesis conditions on adsorption capacity, are studied.

  5. Alginate Production from Alternative Carbon Sources and Use of Polymer Based Adsorbent in Heavy Metal Removal

    Çiğdem Kıvılcımdan Moral

    2016-01-01

    Full Text Available Alginate is a biopolymer composed of mannuronic and guluronic acids. It is harvested from marine brown algae; however, alginate can also be synthesized by some bacterial species, namely, Azotobacter and Pseudomonas. Use of pure carbohydrate sources for bacterial alginate production increases its cost and limits the chance of the polymer in the industrial market. In order to reduce the cost of bacterial alginate production, molasses, maltose, and starch were utilized as alternative low cost carbon sources in this study. Results were promising in the case of molasses with the maximum 4.67 g/L of alginate production. Alginates were rich in mannuronic acid during early fermentation independent of the carbon sources while the highest guluronic acid content was obtained as 68% in the case of maltose. The polymer was then combined with clinoptilolite, which is a natural zeolite, to remove copper from a synthetic wastewater. Alginate-clinoptilolite beads were efficiently adsorbed copper up to 131.6 mg Cu2+/g adsorbent at pH 4.5 according to the Langmuir isotherm model.

  6. Hybrid surfactant-templated mesoporous silica formed in ethanol and its application for heavy metal removal

    With cetyltrimethylammonium (CTAB) and tetramethylammonium hydroxide (TMAOH) as hybrid surfactant templates, a mesoporous adsorbent (adsorbent C) was synthesized in ethanol via the integration of 'One-step' procedure and 'Evaporation-Induced Self-Assembly' procedure. During the synthesis, TMAOH served as the subsidiary structure-directing agent. Adsorbent C exhibited higher pore diameter (centered at 6.1 nm), BET surface area (421.9 m2/g) and pore volume (0.556 cm3/g) than the other two adsorbents only using P123 (adsorbent A) or CTAB (adsorbent B) as the surfactant. The adsorbents were also characterized by XRD and FTIR spectroscopy. The adsorption of copper, zinc, lead, iron, silver and manganese ions on adsorbent C was investigated by contrast tests with adsorbent A and B. The experimental data showed that adsorbent C possessed better adsorption properties than the counterparts. The order of adsorption capacity for six metal ions was Mn2+ 2+ 2+ 2+ 2+ +. The kinetic and thermodynamic properties and the regeneration capacity of adsorbent C were also discussed

  7. Removal of heavy metals from water by zeolite mineral chemically modified. Mercury as a particular case

    Research works on the removal of mercury from water by zeolite minerals show that a small quantity of this element is sorbed. In this work the mercury sorption from aqueous solutions in the presence and absence of Cu(l l), Ni(l l) and/or Zn(l l) by a Mexican zeolite mineral, natural and modified by cisteaminium chloride or cistaminium dichloride, was investigated in acidic p H. The zeolite minerals were characterized by X- Ray diffraction Ftir, scanning electron microscopy and semiquantitative elemental analysis (EDS), surface area analysis (BET) and thermogravimetric analysis (TGA). Mercury from aqueous solutions was quantified by Atomic absorption spectroscopy. The amount of sulphur on the zeolite samples treated with Na CI and modified with cisteaminium chloride (0.375 mmol/g) or cistaminium dichloride(0.475 mmol/g) was found to be higher than that of the zeolite minerals modified with cisteaminium chloride and cistaminium dichloride without treating them with Na CI. The amount of sulphur on the zeolite minerals modified with thiourea was the lowest. The diffusion coefficients and sorption isotherms for mercury were determined in the natural, treated with Na CI and, treated with Na CI and then modified with the cisteaminium chloride or cistaminium dichloride zeolite samples. The retention of mercury was the highest for the zeolite minerals treated Na CI and then modified with cisteaminium chloride or cistaminium dichloride, with adsorption capacity of 0.0511 and 0.0525 mmol Hg/g, respectively. In this research work, it was found that the retention of mercury by the modified minerals was not affected by the presence of Cu (Il), Zn(l l) y Ni (I l) under the experimental conditions. (Author)

  8. Potential application of activated carbon from maize tassel for the removal of heavy metals in water

    Olorundare, O. F.; Krause, R. W. M.; Okonkwo, J. O.; Mamba, B. B.

    Water-pollution problems worldwide have led to an acute shortage of clean and pure water for both domestic and human consumption. Various technologies and techniques are available for water treatment which includes the use of activated carbon. In this study activated carbons used for the removal of lead (II) ions from water samples were prepared from maize tassels (an agricultural waste residue) which were modified using physical and chemical activation. In the physical activation CO2 was used as the activating agent, while in chemical activation H3PO4 with an impregnation ratio ranging from 1 to 4 was employed. The maize tassel was pyrolysed at different temperatures ranging from 300 °C to 700 °C in an inert atmosphere for a period of 60 min and activated at 700 °C for 30 min. The effects of activation temperature, impregnation ratio and duration were examined. The resultant modified tassels were characterised by measuring their particle-size distribution, porosities, pore volume, and pore-size distribution using scanning electron microscopy (SEM). The activated carbon produced by chemical activation had the highest BET surface area ranging from 623 m2 g-1 to 1 262 m2 g-1. The surface chemistry characteristics of the modified tassels were determined by FT-IR spectroscopy and Boehm’s titration method. The experimental data proved that properties of activated carbon depend on final temperature of the process, impregnation ratio and duration of the treatment at final temperature. The adsorption studies showed that chemically prepared activated carbon performed better than physically prepared activated carbon.

  9. Post-annealing treatment for Cu-TiO2 nanotubes and their use in photocatalytic methyl orange degradation and Pb(II) heavy metal ions removal

    Sreekantan, Srimala; Mohd Zaki, Syazwani; Lai, Chin Wei; Tzu, Teoh Wah

    2014-07-01

    TiO2 nanotubes were synthesized via electrochemical anodization of Ti foil at 60 V for 1 h in a bath with electrolytes composed of ethylene glycol containing 5 wt.% of NH4F and 1 vol.% of H2O2. The incorporation of optimum Cu2+ ions (1.30 at.%) into TiO2 nanotubes were prepared by using wet impregnation method to improve their photocatalytic methyl orange degradation and Pb(II) heavy metal removal. The small Cu2+ ions were successfully diffused into lattice of TiO2 nanotubes by conducting post-annealing treatment at 400 °C for 4 h in argon atmosphere after wet impregnation. In this manner, optimum Cu2+ ions played a crucial role in suppressing the recombination of charge carriers by forming inter-band states (mismatch of the band energies) within the lattice of Cu-TiO2. The experimental results showed that a maximum of 80% methyl orange removal and 97.3% Pb(II) heavy metal removal at pH 11 under UV irradiation for 5 h. Besides, it was noticed that photocatalytic Pb(II) heavy metal removal was strong dependence on pH of the solution because of the amphoteric character of Cu-TiO2 in an aqueous medium.

  10. Removal of Heavy Metals Pb2+, Cu2+, Zn2+, Cd2+, Ni2+, Co2+ and Fe3+ from Aqueous Solutions by using Xanthium Pensylvanicum

    Jaber SALEHZADEH

    2013-11-01

    Full Text Available The hazardous ill effects of heavy metals on the environment and public health is a matter of serious concern. Biosorption is emerging as a sustainable effective technology. Heavy metals in water resources are one of the most important environmental problems of countries. The intensification of industrial activity and environmental stress greatly contributes to the significant rise of heavy metal pollution in water resources making threats on terrestrial and aquatic life. The toxicity of metal pollution is slow and interminable, as these metal ions are non bio-degradable. The adsorption capacity of Xanthium Pensylvanicum towards metal ions such as Pb2+, Cu2+, Zn2+, Cd2+, Ni2+, Co2+ and Fe3+, was studied. The adsorption capacity was performed by batch experiments as a function of process parameters (such as sorption time and pH. Experimental results showed that the removal percentages increasing of metal ions at pH=4, initial concentration of metal ions 10 mg/L, and after 90 min of shaking was: Zn2+ < Cd2+ < Cu2+ < Pb2+ < Ni2+ < Fe3+ < Co2+.

  11. Electrodialytic removal of heavy metals from municipal solid waste incineration fly ash using ammonium citrate as assisting agent

    Pedersen, Anne Juul; Ottosen, Lisbeth M.; Villumsen, Arne

    2005-01-01

    was studied, and the results were compared with traditional batch extraction experiments. The application of electric current was found to increase the heavy metal release significantly compared to batch extraction experiments at comparable conditions (same liquid-to-solid ratio, same assisting agent...

  12. Molecular and ionic-scale chemical mechanisms behind the role of nitrocyl group in the electrochemical removal of heavy metals from sludge.

    Hasan, S W; Ahmed, I; Housani, A A; Giwa, A

    2016-01-01

    The chemical basis for improved removal rates of toxic heavy metals such as Zn and Cu from wastewater secondary sludge has been demonstrated in this study. Instead of using excess corrosive chemicals as the source of free nitrous acid (FNA) for improved solubility of heavy metals in the sludge (in order to enhance electrokinetics), an optimized use of aqua regia has been proposed as an alternative. Fragments of nitrocyl group originated from aqua regia are responsible for the disruption of biogenic mixed liquor volatile suspended solids (MLVSS) and this disruption resulted in enhanced removal of exposed and oxidized metal ions. A diversity of nitric oxide (NO), peroxy nitrous acid, and peroxy nitroso group are expected to be introduced in the mixed liquor by the aqua regia for enhanced electrochemical treatment. The effects of pectin as a post treatment on the Zn removal from sludge were also presented for the first time. Results revealed 63.6% Cu and 93.7% Zn removal efficiencies, as compared to 49% Cu and 74% Zn removal efficiencies reported in a recent study. Also, 93.3% reduction of time-to-filter (TTF), and 95 mL/g of sludge volume index (SVI) were reported. The total operating cost obtained was USD 1.972/wet ton. PMID:27550724

  13. A novel reusable nanocomposite for complete removal of dyes, heavy metals and microbial load from water based on nanocellulose and silver nano-embedded pebbles.

    Suman; Kardam, Abhishek; Gera, Meeta; Jain, V K

    2015-01-01

    The present work proposed a nanocellulose (NC)-silver nanoparticles (AgNPs) embedded pebbles-based composite material as a novel reusable cost-effective water purification device for complete removal of dyes, heavy metals and microbes. NC was prepared using acid hydrolysis of cellulose. The AgNPs were generated in situ using glucose and embedded within the porous concrete pebbles by the technique of inter-diffusion of ion, providing a very strong binding of nanoparticles within the porous pebbles and thus preventing any nanomaterials leaching. Fabrication of a continual running water purifier was achieved by making different layering of NC and Ag nano-embedded pebbles in a glass column. The water purifier exhibited not only excellent dye and heavy metal adsorption capacity, but also long-term antibacterial activity against pathogenic and non-pathogenic bacterial strains. The adsorption mainly occurred through electrostatic interaction and pore diffusion also contributed to the process. The bed column purifier has shown 99.48% Pb(II) and 98.30% Cr(III) removal efficiency along with 99% decontamination of microbial load at an optimum working pH of 6.0. The high adsorption capacity and reusability, with complete removal of dyes, heavy metals and Escherichia coli from the simulated contaminated water of composite material, will provide new opportunities to develop a cost-effective and eco-friendly water purifier for commercial application. PMID:25243917

  14. Biosorption of Heavy Metals by Biomass

    AKÇİN, Göksel

    2001-01-01

    Wetland plants are successfully used in the biosorption of heavy metals in natural and constructed wetlands. In this study, the removal of heavy metals by water hyacinth [ Eichhornia crassipes (Mart.)Solms)] were investigated. The plants were grown under control in the Turkish climate. The biosorption was dependent on factors such as metal concentration, constant temperature, pH and relative moisture. The plants were exposed to different metal concentrations of Chromium(III), Chromi...

  15. Cr(VI) removal from aqueous solution by thermophilic denitrifying bacterium Chelatococcus daeguensis TAD1 in the presence of single and multiple heavy metals.

    Li, Han; Huang, Shaobin; Zhang, Yongqing

    2016-09-01

    Cr(VI) pollution is increasing continuously as a result of ongoing industrialization. In this study, we investigated the thermophilic denitrifying bacterium Chelatococcus daeguensis TAD1, isolated from the biofilm of a biotrickling filter used in nitrogen oxides (NOX) removal, with respect to its ability to remove Cr(VI) from an aqueous solution. TAD1 was capable of reducing Cr(VI) from an initial concentration of 10 mg/L to non-detectable levels over a pH range of 7-9 and at a temperature range of 30-50°C. TAD1 simultaneously removed both Cr(VI) and NO3 (-)-N at 50°C, when the pH was 7 and the initial Cr(VI) concentration was 15 mg/L. The reduction of Cr(VI) to Cr(III) correlated with the growth metabolic activity of TAD1. The presence of other heavy metals (Cu, Zn, and Ni) inhibited the ability of TAD1 to remove Cr(VI). The metals each individually inhibited Cr(VI) removal, and the extent of inhibition increased in a cooperative manner in the presence of a combination of the metals. The addition of biodegradable cellulose acetate microspheres (an adsorption material) weakened the toxicity of the heavy metals; in their presence, the Cr(VI) removal efficiency returned to a high level. The feasibility and applicability of simultaneous nitrate removal and Cr(VI) reduction by strain TAD1 is promising, and may be an effective biological method for the clean-up of wastewater. PMID:27572509

  16. Layered Double Hydroxides as Effective Adsorbents for U(VI and Toxic Heavy Metals Removal from Aqueous Media

    G. N. Pshinko

    2013-01-01

    Full Text Available Capacities of different synthesized Zn,Al-hydrotalcite-like adsorbents, including the initial carbonate [Zn4Al2(OH12]·CO3·8H2O and its forms intercalated with chelating agents (ethylenediaminetetraacetic acid (EDTA, diethylenetriaminepentaacetic acid (DTPA, and hexamethylenediaminetetraacetic acid (HMDTA and heat-treated form Zn4Al2O7, to adsorb uranium(VI and ions of toxic heavy metals have been compared. Metal sorption capacities of hydrotalcite-like adsorbents have been shown to correlate with the stability of their complexes with the mentioned chelating agents in a solution. The synthesized layered double hydroxides (LDHs containing chelating agents in the interlayer space are rather efficient for sorption purification of aqueous media free from U(VI irrespective of its forms of natural abundance (including water-soluble bi- and tricarbonate forms and from heavy metal ions. [Zn4Al2(OH12]·EDTA·nH2O is recommended for practical application as one of the most efficient and inexpensive synthetic adsorbents designed for recovery of both cationic and particularly important anionic forms of U(VI and other heavy metals from aqueous media. Carbonate forms of LDHs turned out to be most efficient for recovery of Cu(II from aqueous media with pH0≥7 owing to precipitation of Cu(II basic carbonates and Cu(II hydroxides. Chromate ions are efficiently adsorbed from water only by calcinated forms of LDHs.

  17. Application of zeolite-Arthrobacter viscosus system for the removal of heavy metal and dye : chromium and azure B

    Rosales, E.; Pazos, M.; Sanromán, M. A.; Tavares, M. T.

    2012-01-01

    A hybrid system combining the ion-exchange properties of a NaY zeolite and the characteristics of the bacterium Arthrobacter viscosus was investigated to treat polluted effluents with dye and toxic metals. In this study, the dye and the metal ion employed were a thiazine dye, Azure B, and chromium (VI), respectively. Initially, the removal of dye by the zeolite was tested. The analysis of dye equilibrium isotherms data was done using Langmuir, Freundlich, Sips and Redlich–Peterson models. Red...

  18. Efficient removal of heavy metal ions from aqueous systems with the assembly of anisotropic layered double hydroxide nanocrystals@carbon nanosphere.

    Gong, Jingming; Liu, Ting; Wang, Xiaoqing; Hu, Xianluo; Zhang, Lizhi

    2011-07-15

    We report on the efficient removal of heavy metal ions from simulated wastewater with a nanostructured assembly. The nanoassembly was obtained via direct assembling the performed anisotropic layered double hydroxide nanocrystals (LDH-NCs) onto the surface of carbon nanospheres (labeled as LDH-NCs@CNs). It was found that the maximum adsorption capacity of the nanoassembly toward Cu(2+) was ∼ 19.93 mg g(-1) when the initial Cu(2+) concentration was 10.0 mg L(-1), displaying a high efficiency for the removal of heavy metal ions. The Freundlich adsorption isotherm was applicable to describe the removal processes. Kinetics of the Cu(2+) removal was found to follow pseudo-second-order rate equation. Furthermore, the as-prepared building unit of the assembly, including LDH-NCs, CNs, and the assembly, as well as Cu(2+)-adsorbed assembly, were carefully examined by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), nitrogen sorption measurements, and X-ray photoelectron spectroscopy (XPS). Based on the characterization results, a possible mechanism of Cu(2+) removal with the assembly of LDH-NCs@CNs was proposed. Comparison experiments show that the adsorption capacity of the resulting LDH-NCs@CNs assembly was much higher than its any building unit alone (CNs or LDH-NCs), exhibiting the deliberation of the assembly on water decontamination. This work provides a very efficient, fast and convenient approach for exploring promising nanoassembly materials for water treatment. PMID:21692502

  19. Layered Double Hydroxides as Effective Adsorbents for U(VI) and Toxic Heavy Metals Removal from Aqueous Media

    G. N. Pshinko

    2013-01-01

    Capacities of different synthesized Zn,Al-hydrotalcite-like adsorbents, including the initial carbonate [Zn4Al2(OH)12]·CO3·8H2O and its forms intercalated with chelating agents (ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), and hexamethylenediaminetetraacetic acid (HMDTA)) and heat-treated form Zn4Al2O7, to adsorb uranium(VI) and ions of toxic heavy metals have been compared. Metal sorption capacities of hydrotalcite-like adsorbents have been shown to corr...

  20. Coupled Electrokinetics-Adsorption Technique for Simultaneous Removal of Heavy Metals and Organics from Saline-Sodic Soil

    Salihu Lukman; Mohammed Hussain Essa; Nuhu Dalhat Mu'azu; Alaadin Bukhari

    2013-01-01

    In situ remediation technologies for contaminated soils are faced with significant technical challenges when the contaminated soil has low permeability. Popular traditional technologies are rendered ineffective due to the difficulty encountered in accessing the contaminants as well as when employed in settings where the soil contains mixed contaminants such as petroleum hydrocarbons, heavy metals, and polar organics. In this study, an integrated in situ remediation technique that couples elec...

  1. In vitro removal of toxic heavy metals by poly(γ-glutamic acid)-coated superparamagnetic nanoparticles

    Chen, Bin-Huei

    2012-01-01

    Baskaran Stephen Inbaraj,1 Bing-Huei Chen1,21Department of Food Science, 2Graduate Institute of Medicine, Fu Jen University, Taipei, TaiwanBackground: Chelation therapy involving organic chelators for treatment of heavy metal intoxication can cause cardiac arrest, kidney overload, mineral deficiency, and anemia.Methods: In this study, superparamagnetic iron oxide nanoparticles (SPIONs) modified with an edible biopolymer poly(γ-glutamic acid) (PGA) were synthesized by coprecipitation...

  2. Facile preparation of highly hydrophilic, recyclable high-performance polyimide adsorbents for the removal of heavy metal ions.

    Huang, Jieyang; Zheng, Yaxin; Luo, Longbo; Feng, Yan; Zhang, Chaoliang; Wang, Xu; Liu, Xiangyang

    2016-04-01

    To obtain high-performance adsorbents that combine excellent adsorption ability, thermal stability, service life and recycling ability, polyimide (PI)/silica powders were prepared via a facile one-pot coprecipitation process. A benzimidazole unit was introduced into the PI backbone as the adsorption site. The benzimidazole unit induced more hydroxyls onto the silica, which provided hydrophilic sites for access by heavy metal ions. By comprehensively analyzing the effect of hydrophilcity, agglomeration, silica polycondensation, specific surface area and PI crystallinity, 10% was demonstrated to be the most proper feed silica content. The equilibrium adsorption amount (Qe) for Cu(2+) of PI/silica adsorbents was 77 times higher than that of pure PI. Hydrogen chloride (HCl) was used as a desorbent for heavy metal ions and could be decomplexed with benzimidazole unit at around 300°C, which was lower than the glass transition temperature of PI. The complexation and decomplexation process of HCl made PI/silica adsorbents recyclable, and the adsorption ability remained steady for more than 50 recycling processes. As PI/silica adsorbents possess excellent thermal stability, chemical resistance and radiation resistance and hydrophilicity, they have potential as superior recyclable adsorbents for collecting heavy metal ions from waste water in extreme environments. PMID:26736172

  3. Biofilm establishment and heavy metal removal capacity of an indigenous mining algal-microbial consortium in a photo-rotating biological contactor.

    Orandi, S; Lewis, D M; Moheimani, N R

    2012-09-01

    An indigenous mining algal-microbial consortium was immobilised within a laboratory-scale photo-rotating biological contactor (PRBC) that was used to investigate the potential for heavy metal removal from acid mine drainage (AMD). The microbial consortium, dominated by Ulothrix sp., was collected from the AMD at the Sar Cheshmeh copper mine in Iran. This paper discusses the parameters required to establish an algal-microbial biofilm used for heavy metal removal, including nutrient requirements and rotational speed. The PRBC was tested using synthesised AMD with the multi-ion and acidic composition of wastewater (containing 18 elements, and with a pH of 3.5 ± 0.5), from which the microbial consortium was collected. The biofilm was successfully developed on the PRBC's disc consortium over 60 days of batch-mode operation. The PRBC was then run continuously with a 24 h hydraulic residence time (HRT) over a ten-week period. Water analysis, performed on a weekly basis, demonstrated the ability of the algal-microbial biofilm to remove 20-50 % of the various metals in the order Cu > Ni > Mn > Zn > Sb > Se > Co > Al. These results clearly indicate the significant potential for indigenous AMD microorganisms to be exploited within a PRBC for AMD treatment. PMID:22644382

  4. Heavy metals removal from acid mine drainage water using biogenic hydrogen sulphide and effluent from anaerobic treatment: Effect of pH

    Jimenez-Rodriguez, A.M. [Departamento de Sistemas Fisicos, Quimicos y Naturales, Facultad de Ciencias Ambientales, Universidad Pablo de Olavide. Carretera de Utrera, km 1. 41013 Sevilla (Spain); Duran-Barrantes, M.M. [Departamento de Ingenieria Quimica, Facultad de Quimica, Universidad de Sevilla, C/Profesor Garcia Gonzalez, s/n, 41071 Sevilla (Spain); Borja, R., E-mail: rborja@cica.es [Consejo Superior de Investigaciones Cientificas (CSIC), Instituto de la Grasa, Avda. Padre Garcia Tejero 4, 41012 Sevilla (Spain); Sanchez, E.; Colmenarejo, M.F. [Consejo Superior de Investigaciones Cientificas (CSIC), Centro de Ciencias Medioambientales, C/Serrano, 115-duplicado, 28006 Madrid (Spain); Raposo, F. [Consejo Superior de Investigaciones Cientificas (CSIC), Instituto de la Grasa, Avda. Padre Garcia Tejero 4, 41012 Sevilla (Spain)

    2009-06-15

    Four alternatives (runs A, B, C and D) for heavy metals removal (Fe, Cu, Zn and Al) from acid mine drainage water (AMDW) produced in the mining areas of the Huelva Province, Spain, were evaluated. In run A, the anaerobic effluent from the treatment of acid mine drainage water (cheese whey added as a source of carbon) was mixed with the raw AMDW. The pH increased to 3.5 with the addition of KOH. In run B, biogas with around 30% of hydrogen sulphide obtained in the anaerobic reactor was sparged to the mixture obtained in run A, but in this case at a pH of 5.5. In run C, the pH of the raw AMDW was increased to 3.5 by the addition of KOH solution. Finally, in run D, the pH of the raw AMDW was increased to 5.5 by the addition of KOH solution and further biogas was sparged under the same conditions as in run A. It was found that heavy metal removal was a function of pH. At a pH of 3.5 most of the iron was removed while Zn and Cu were partially removed. At a pH of 5.5 the removal of all metals increased considerably. The best results were obtained in run B where the percentages of removal of Fe, Cu, Zn and Al achieved values of 91.3, 96.1, 79.0 and 99.0%, respectively. According to the experimental results obtained tentative schemas of the flow diagram of the processes were proposed.

  5. Heavy metals removal from acid mine drainage water using biogenic hydrogen sulphide and effluent from anaerobic treatment: Effect of pH

    Four alternatives (runs A, B, C and D) for heavy metals removal (Fe, Cu, Zn and Al) from acid mine drainage water (AMDW) produced in the mining areas of the Huelva Province, Spain, were evaluated. In run A, the anaerobic effluent from the treatment of acid mine drainage water (cheese whey added as a source of carbon) was mixed with the raw AMDW. The pH increased to 3.5 with the addition of KOH. In run B, biogas with around 30% of hydrogen sulphide obtained in the anaerobic reactor was sparged to the mixture obtained in run A, but in this case at a pH of 5.5. In run C, the pH of the raw AMDW was increased to 3.5 by the addition of KOH solution. Finally, in run D, the pH of the raw AMDW was increased to 5.5 by the addition of KOH solution and further biogas was sparged under the same conditions as in run A. It was found that heavy metal removal was a function of pH. At a pH of 3.5 most of the iron was removed while Zn and Cu were partially removed. At a pH of 5.5 the removal of all metals increased considerably. The best results were obtained in run B where the percentages of removal of Fe, Cu, Zn and Al achieved values of 91.3, 96.1, 79.0 and 99.0%, respectively. According to the experimental results obtained tentative schemas of the flow diagram of the processes were proposed.

  6. Recycling of agricultural solid waste, coir pith: Removal of anions, heavy metals, organics and dyes from water by adsorption onto ZnCl2 activated coir pith carbon

    The abundant lignocellulosic agricultural waste, coir pith is used to develop ZnCl2 activated carbon and applied to the removal of toxic anions, heavy metals, organic compounds and dyes from water. Sorption of inorganic anions such as nitrate, thiocyanate, selenite, chromium(VI), vanadium(V), sulfate, molybdate, phosphate and heavy metals such as nickel(II) and mercury(II) has been studied. Removal of organics such as resorcinol, 4-nitrophenol, catechol, bisphenol A, 2-aminophenol, quinol, O-cresol, phenol and 2-chlorophenol has also been investigated. Uptake of acidic dyes such as acid brilliant blue, acid violet, basic dyes such as methylene blue, rhodamine B, direct dyes such as direct red 12B, congo red and reactive dyes such as procion red, procion orange were also examined to assess the possible use of the adsorbent for the treatment of contaminated ground water. Favorable conditions for maximum removal of all adsorbates at the adsorbate concentration of 20 mg/L were used. Results show that ZnCl2 activated coir pith carbon is effective for the removal of toxic pollutants from water

  7. Heavy metal removal from wastewater using phragmites australis-voltammetric study of the interaction between heavy metals and the chemical constituents of phragmites australis

    This is the first study of the complexation between metal ions and compounds isolated from a plant used in constructed wetlands. The relation between the chemical constituents of phragmites australis and the ability of the plant to uptake metal ions from wastewater has been investigated. Eighteen compounds were separated and identified from the butanolic extract of Phragmites australis. Seven of which are flavonoid glycosides. The main flavone glycoside isolated was tricin-7-O-beta-D-glucopyranoside. Complexes of Pb(II), Cd(II), Ni(II) and Zn(II) with the butanolic extract, tricin-7-O-beta-D-glucopyranoside and tricin were studied by different pulse polarography, under the optimum conditions of complex formation of each metal. It was found that Pb(II) and Cd(II) from 1:2 complex with each of the three ligands only in basic media. The conditional formation constants and the coordination numbers of the complexes formed between Pb(II) and the butanolic extract, tricin-7-O-beta-D-glucopyranoside and tricin were of comparable values indicating that the compounds in the butanolic extract that formed complexes with lead are most likely flavonoids. The same was observed in the case of Cd(II) ion. Nickel(II) ion formed a 1:2 complex with the crude butanolic extract and 1:1 complex with tricin-7-O-beta-D-glucopyranoside in basic media. Overlapping signals prevented the detection of complexes with higher coordination numbers. Complex formation between Ni(II) and tricin was indicated by the shifts in the peak potential of Ni(II) induced by ligand addition, but the presence of overlapping peaks prevented further studies. For Zinc(II) ion, complexation with the three ligands in basic media was indicated by the shifts in the peak potential of Zn(II). The presence of overlapping peaks prevented the determination of the formation constant and the coordination number. Nevertheless, the formation constant of a 1:2 complex between Zn(II) and butanolic extract was determined in acidic

  8. Self-assembled 3D flower-like α-Fe2O3 microstructures and their superior capability for heavy metal ion removal

    Hierarchically 3D flower-like α-Fe2O3 microstructures have been synthesized through a urea-assisted hydrothermal synthetic route. The product was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The as-prepared product was consisted of hierarchically flow-like microstructures assembled from nanopetal subunits. The effects of the urea and NaOH on the morphology of the products were systematically studied, and a possible formation mechanism of the α-Fe2O3 microflowers was proposed based on the experimental results. These flower-like α-Fe2O3 microstructures were used as adsorbent for water treatment, and the results revealed excellent performance for heavy metal ion removal. With maximum capacities of 41.46 and 33.82 mg g−1 for As(V) and Cr(VI), respectively, such flower-like α-Fe2O3 microstructures are expected to be an attractive adsorbent for the removal of heavy metal ions from water. - Graphical abstract: Display Omitted - Highlights: • 3D flower-like hematite microstructures were synthesized by a hydrothermal method. • The formation mechanism of flower-like microstructures was proposed. • Effective removal of As(V) and Cr(VI) from aqueous solution

  9. Studies on the Use of Supported Liquid Membrane Technique for Removal of Heavy Metals from Water Effluents

    The present work is directed to develop, assess and establish different systems for the removal and recovery of Co, Ni, Zn and Cd from aqueous solutions using supported liquid membrane (SLM) technique. The individual permeation of Co(II) and Ni(II) from aqueous chloride solutions through SLM using CYANEX 301 in kerosene supported on cellulose acetate membrane was studied based on the optimum conditions for separation obtained by liquid-liquid extraction experiments. Application studies of the investigated system were carried out on the permeation of four heavy elements (Co(II), Ni(II), Zn(II) and Cd(II) ) of equal concentrations when mixed together in real water samples from different origins. For this purpose, samples from Ismailia canal, El-Manzala lake, sea water and drinking water were selected for these experiments. The results obtained show that complete removal of Zn(II) from aqueous chloride medium of ph 3 from El-Manzala lake water is obtained at different temperature degrees and the removal of a large amounts of Co(II), Cd(II) and Ni(II) from drinking water is also possible.

  10. Simultaneous removal of heavy-metal ions in wastewater samples using nano-alumina modified with 2,4-dinitrophenylhydrazine.

    Afkhami, Abbas; Saber-Tehrani, Mohammad; Bagheri, Hasan

    2010-09-15

    2,4-Dinitrophenylhydrazine (DNPH) immobilized on sodium dodecyl sulfate coated nano-alumina was developed for the removal of metal cations Pb(II), Cd(II), Cr(III), Co(II), Ni(II) and Mn(II) from water samples. The research results displayed that adsorbent has the highest adsorption capacity for Pb(II), Cr(III) and Cd(II) in ions mixture system. Optimal experimental conditions including pH, adsorbent dosage and contact time have been established. Langmuir and Freundlich isotherm models were applied to analyze the experimental data. The best interpretation for the experimental data was given by the Freundlich adsorption isotherm equation for Mn(II), Pb(II), Cr(III) and Cd(II) ions and by Langmuir isotherm equation for Ni(II) and Co(II) ions. Desorption experiments by elution of the adsorbent with a mixture of nitric acid and methanol show that the modified alumina nanoparticles could be reused without significant losses of its initial properties even after three adsorption-desorption cycles. Thus, modified nano-alumina with DNPH is favorable and useful for the removal of these metal ions, and the high adsorption capacity makes it a good promising candidate material for Pb(II),Cr(III) and Cd(II) removal. PMID:20542378

  11. Cost effective and shape controlled approach to synthesize hierarchically assembled NiO nanoflakes for the removal of toxic heavy metal ions in aqueous solution

    K Yogesh Kumar; H B Muralidhara; Y Arthoba Nayaka; H Hanumanthappa; M S Veena; S R Kiran Kumar

    2015-02-01

    Hierarchical mesoporous NiO nanoflakes (NiOs) have been synthesized in high yield via a simple, economical and environmentally friendly hydrothermal route. The as-prepared NiOs were characterized by powder X-ray diffraction (PXRD), scanning electronicmicroscopy (SEM), transmission electronmicroscopy (TEM), selected area electron diffraction patterns (SAED), X-ray energy dispersive spectroscopy (EDS) and nitrogen adsorption–desorption techniques (Brunauer–Emmett–Teller, BET). Adsorption of heavy metal ions onto the as-prepared sample from aqueous solutions was investigated using differential pulse anodic stripping voltametry (DPASV) technique and discussed. The product possesses a BET surface area of 69.27 m2 g-1. It is found that NiOs exhibited the excellent performance for the removal of Hg(II), Pb(II) and Cd(II) from aqueous solution. The equilibrium adsorption data of Hg(II), Pb(II) and Cd(II) on the as-prepared NiOs were analyzed by Langmuir and Freundlich models, suggesting that the Langmuir model provides the better correlation of the experimental data. The adsorption capacities for removal of Hg(II), Pb(II) and Cd(II) were determined using the Langmuir equation and found to be 1324.5, 1428.9 and 1428.5 mg g-1, respectively. Adsorption kinetics of all the metal ions followed pseudo second-order model. Moreover, NiOs can be recycled by simple acid treatment, which could retain the high removal efficiency in three successive cycles. This study suggests that nanoflakes could be explored as a new adsorbent with high efficiency and recyclability for removing heavy metal ions from aqueous solution.

  12. Application of mucilage from Dicerocaryum eriocarpum plant as biosorption medium in the removal of selected heavy metal ions.

    Jones, Bassey O; John, Odiyo O; Luke, Chimuka; Ochieng, Aoyi; Bassey, Bridget J

    2016-07-15

    The ability of mucilage from Dicerocaryum eriocarpum (DE) plant to act as biosorption medium in the removal of metals ions from aqueous solution was investigated. Functional groups present in the mucilage were identified using Fourier transform infrared spectroscopy (FTIR). Mucilage was modified with sodium and potassium chlorides. This was aimed at assessing the biosorption efficiency of modified mucilage: potassium mucilage (PCE) and sodium mucilage (SCE) and comparing it with non-modified deionised water mucilage (DCE) in the uptake of metal ions. FTIR results showed that the functional groups providing the active sites in PCE and SCE and DCE include: carboxyl, hydroxyl and carbonyl groups. The chloride used in the modification of the mucilage did not introduce new functional groups but increased the intensity of the already existing functional groups in the mucilage. Results from biosorption experiment showed that DE mucilage displays good binding affinity with metals ions [Zn(II), Cd(II) Ni(II), Cr(III) and Fe(II)] in the aqueous solution. Increase in the aqueous solution pH, metal ions initial concentration and mucilage concentration increased the biosorption efficiency of DE mucilage. The maximum contact time varied with each species of metal ions. Optimum pH for [Zn(II), Cd(II) Ni(II) and Fe(II)] occurred at pH 4 and pH 6 for Cr(III). Kinetic models result fitted well to pseudo-second-order with a coefficient values of R(2) = 1 for Cd(II), Ni(II), Cr(III), Fe(II) and R(2) = 0.9974 for Zn(II). Biosorption isotherms conforms best with Freundlich model for all the metal ions with correlation factors of 0.9994, 0.9987, 0.9554, 0.9621 and 0.937 for Zn(II), Ni(II), Fe(II), Cr(III) and Cd(II), respectively. Biosorption capacity of DE mucilage was 0.010, 2.387, 4.902, 0688 and 0.125 for Zn(II), Cr(III), Fe(II), Cd(II) and Ni(II) respectively. The modified mucilage was found to be highly efficient in the removal of metal ions than the unmodified mucilage. PMID

  13. Heavy metals removal in wastewater by activated carbon adsorption and clays of cationic interchange; Eliminacion de metales pesados en disolucion mediante adsorcion en carbon activo y arcillas de intercambio cationico

    Montes, M. A.; Medialdea, J. M.; Garcia Mediavilla, B.; Moron, M. J.; Arnaiz, M. C.; Garcia Martinez de Simon, I.; Lopez, C. M.; Escot, E.; Lebrato, J. [Universidad de Sevilla. Sevilla (Spain)

    1999-11-01

    Among the different treatment systems assessed for the purification of the wastewaters poured from Aznalcollar quarry the last April 25, 1998, physical and chemical adsorption proved highly efficient for the removal of refractory heavy metals. In laboratory experiments, 99% of dissolved Mn and Zn was removed when wastewater passed through a packedbed column filled with a cationic exchange clay. In the same way, activated-carbon adsorption removed more than 80% of dissolved Zn and 11-16% of Mn. Results confirm the feasibility of these processes and contribute knowledge on their operational characteristics so that in any other similar situation we can consider all treatment possibilities. 8 refs.

  14. Optimization of process parameters for removal of heavy metals by biomass of Cu and Co-doped alginate-coated chitosan nanoparticles.

    Esmaeili, Akbar; Khoshnevisan, Najmeh

    2016-10-01

    In this study, the efficiency of alginate-coated chitosan nanoparticles (Alg-CS-NPs) for removal of heavy metals from industrial effluents was investigated. To this end, the researchers constructed a reactor containing biomass, using response surface methodology (RSM) for process optimization. Reactor tests were carried out with both synthetic and industrial effluents containing nickel. The optimum conditions to achieve maximum removal efficiency (RE) rates for both synthetic and industrial effluents were specified for contact time (0-120min), pH level (1-9), biomass dose (0.1-0.9g), and initial metal ion concentration (10-90mg/L). It was determined that 94.48% of the nickel could be removed at pH=3, 70mg/L initial nickel concentration, a dose of 0.3g biomass, and 30min contact time. The kinetic data fit well to a pseudo second-order model and the equilibrium data of the metal ions could be described well with Freundlich isotherm models. PMID:27416515

  15. The use of new modified poly(acrylamide chelating resin with pendent benzothiazole groups containing donor atoms in the removal of heavy metal ions from aqueous solutions

    Semmedu Selvaraj Kalaivani

    2014-03-01

    Full Text Available The adsorption studies of poly(6-(ethoxybenzothiazole acrylamide (PEBTA, for Cu(II and Zn(II metal ions removal from an aqueous solution have been investigated, as a function of solution pH, adsorbent dose, contact time, initial metal ion concentration and temperature. The chemical and structural characteristics of the adsorbent were determined by the FT-IR, 1H-NMR, TGA, SEM, and EDAX analysis. The maximum adsorption capacities of the adsorbent for Cu(II and Zn(II ions, as calculated from the Langmuir isotherm model, were 273.5 and 216.4 mg/g, respectively. The adsorption kinetic studies show that the adsorption of Cu(II and Zn(II ions onto PEBTA follows the pseudo second order kinetic model. Thermodynamic parameters such as ΔG°, ΔH° and ΔS° were also evaluated, and it has been found that the adsorption process is feasible, spontaneous and exothermic in nature. Desorption studies were carried out using 0.3 N HCl, and it revealed that the adsorbed Cu(II and Zn(II ions can be easily removed. The adsorption–desorption process is reversible, and this indicates that PEBTA is an effective adsorbent for the removal of heavy metal ions from an aqueous medium.

  16. Application of Gamma Radiation to Enhance Heavy Metals Removal Efficiency to Bacteria Isolated from Ronpiboon District, Nakhon Sri Thamarat Province, Thailand

    The objective of this study was to isolate soil bacteria capable to te move 4 heavy metals, namely, arsenic (As(III)), lead Pb(II) and cadmium f ron old tin mine in Ronpiboon district, Nakhon Sri Thamarat. It was found that there were bacteria which capable to resist arsenic, lead and copper 11, 15, 8 and 2 ileitis, respectively[evacuate;y. The arsenic removal efficiency of these bacteria was evaluated at the low concentration of 1 u g/l. with the results of 7-61%. The lead and copper removal efficiencies at 10 mg/l were found at the range pf 9-98% and 8-40%, respectively. Six isolates of bacteria (KRD, KRH, KRM, KCD13 and KCD14) were selected to be irradiated by gamma radiation at the levels of 2-10 kGy. The heavy metals resistance was found increase in the range of of 125-16% for arsenic, 0-50% for copper, 0-18% for lead and 0-17% for cadmium, respectively. Also ut was found that the low temperature at 4 and -40 degree Celsius can prolong the bacterial survival up to 6 months. Later the arsenic removal experiment in liquid medium was conducted and it was found that the mutants can perform slightly better than wild type only >17%. It was due to the initial concentration of arsenic was too high (10 mg/l). The preliminary study of arsenic removal in soil was also conducted using pack-bed reactor. We found the proper ratio of pack material (soil and gravel) was 1:1 to promote the liquid and air circulation. The suitable medium was found to be acidified mo lass solution which were found promote the growth of tested bacterial isolates.

  17. Synthesis of LTA zeolite on corundum supports: Preliminary assessment for heavy metal removal from waste water; Sintesis de zeolita LTA sobre soportes de corindon: Evaluacion preliminar para la eliminacion de metales pesados de efluentes acuosos

    Jacas, A.; Ortega, P.; Velasco, M. J.; Camblor, M. A.; Rodriguez, M. A.

    2012-11-01

    The effectiveness of materials based on LTA Zeolite as active phase, for their incorporation into systems aimed at the removal of heavy metals on waste water is evaluated in a preliminary way. This type of Zeolite with the main channel of a minimum free diameter of 0,41 nm and a low SiO{sub 2}/Al{sub 2}O{sub 3} ratio is an interesting molecular sieve, which in turn display a high ion exchange capacity. From this point of view, LTA Zeolite crystals were obtained in situ by hydrothermal synthesis and characterized by x ray diffraction (XRD) and scanning electron microscopy (SEM). We have studied the effect of hydrothermal synthesis time at 378 K. Likewise, the removal capacity of heavy metal from the active phase was evaluated in as a first step on diluted solutions of cooper salts at slightly acidic pH ({approx} 4,7). (Author) 28 refs.

  18. Potato peels as solid waste for the removal of heavy metal copper(II) from waste water/industrial effluent.

    Aman, Tehseen; Kazi, Asrar Ahmad; Sabri, Muhammad Usman; Bano, Qudsia

    2008-05-01

    A new sorbent potato peels, which are normally discarded as solid waste for removing toxic metal ion Cu(II) from water/industrial waste water have been studied. Potato peels charcoal (PPC) was investigated as an adsorbent of Cu(II) from aqueous solutions. Kinetic and isotherm studies were carried out by studying the effects of various parameters such as temperature, pH and solid liquid ratios. The optimum pH value for Cu(II) adsorption onto potato peels charcoal (PPC) was found to be 6.0. The thermodynamic parameters such as standard Gibb's free energy (Delta G degrees ), standard enthalpy (Delta H degrees ) and standard entropy (DeltaS degrees ) were evaluated by applying the Van't Hoff equation. The thermodynamics of Cu(II) adsorption onto PPC indicates its spontaneous and exothermic nature. The equilibrium data at different temperatures were analyzed by Langmuir and Freundlich isotherms. PMID:18215510

  19. Heavy metal removal from sludge with organic chelators: Comparative study of N, N-bis(carboxymethyl) glutamic acid and citric acid.

    Suanon, Fidèle; Sun, Qian; Dimon, Biaou; Mama, Daouda; Yu, Chang-Ping

    2016-01-15

    The applicability and performance of a new generation of biodegradable chelator, N, N-Bis(carboxymethyl) glutamic acid (GLDA), for extracting heavy metals from sewage sludge was carried out and compared with citric acid (CA). Targeted metals included Cd, Co, Cu, Zn, Ni and Cr, and their contents in the raw sludge were 63.1, 73.4, 1103.2, 2060.3, 483.9 and 604.1 mg kg(-1) (dry sludge basis), respectively. Metals were divided into six fractions including water soluble, exchangeable, carbonates bound, Fe-Mn bound, organic matters bound and residual fraction via chemical fractionation. Washing results showed that in general GLDA exhibited better performance compared with CA, with removal efficiency of 83.9, 87.3, 81.2, 85.6, 89.3 and 90.2% for Cd, Co, Cu, Zn, Ni and Cr, respectively at equilibrium pH = 3.3. Residual metals were better stabilized in the GLAD-washed sludge than in the CA-washed sludge, and were mostly tightly bonded to the residual fraction. Furthermore, CA promoted phosphorus (P) release while GLDA had an opposite effect and tended to retain P within sludge, which could be beneficial for further application in agricultural use. Findings from this study suggested that GLDA could be a potential replacement for refractory and less environmentally-friendly chelators in the extraction of metals from sludge. PMID:26520041

  20. Functionalized calcium silicate nanofibers with hierarchical structure derived from oyster shells and their application in heavy metal ions removal.

    You, Weijie; Hong, Mingzhu; Zhang, HaiFeng; Wu, Qiuping; Zhuang, Zanyong; Yu, Yan

    2016-06-21

    Inorganic hierarchical nanostructures have remarkable potential applications in environmental metal remediation; however, their applications usually suffer from low capacity, high cost, and difficulties in the recycling of adsorbents. We previously reported a facile strategy to synthesize acid-insoluble calcium silicate hydrates (CSH) from oyster shells, a representative kind of biowaste. However, little is known of the structure, size, and morphology of the as-prepared CSH, which hampers the improvement of their adsorption capacities. In this work, systematic investigation of the structures of as-generated CSH demonstrate that they have a hierarchically porous structure composed of thin nano-sheets, where each nano-sheet is assembled by nano-fibers with width of around ten nanometers. The hierarchical nanostructures with pore size of ∼12 nm provide a significant amount of active sites to graft polyethyleneimine (PEI), which enables the efficient extraction of both Cu(ii) cations and Cr(vi) anions from the aqueous solution. Batch experiments further indicate that the PEI-modified PCSH exhibit a maximum adsorption capacity of 203 and 256 mg g(-1) for Cu(ii) and Cr(vi), respectively, much higher than that of CSH, OS and many other adsorbents in literature. The adsorption of Cu(ii) and Cr(vi) proved to be spontaneous and exothermic. Combining the pH-dependent experiments with X-ray photoelectron spectroscopy analysis, the underlying mechanism is discussed. PCSH derived from OS biowaste maintains an efficient extraction ability toward Cu(ii) and Cr(vi) after five adsorption-desorption cycles. It is also applicable for treating various kinds of heavy metal ions and organic pollutants, showing potentially wide applications in water treatment. PMID:27221228

  1. Synthesis of MnFe2O4@Mn-Co oxide core-shell nanoparticles and their excellent performance for heavy metal removal.

    Ma, Zichuan; Zhao, Dongyuan; Chang, Yongfang; Xing, Shengtao; Wu, Yinsu; Gao, Yuanzhe

    2013-10-21

    Magnetic nanomaterials that can be easily separated and recycled due to their magnetic properties have received considerable attention in the field of water treatment. However, these nanomaterials usually tend to aggregate and alter their properties. Herein, we report an economical and environmentally friendly method for the synthesis of magnetic nanoparticles with core-shell structure. MnFe2O4 nanoparticles have been successfully coated with amorphous Mn-Co oxide shells. The synthesized MnFe2O4@Mn-Co oxide nanoparticles have highly negatively charged surface in aqueous solution over a wide pH range, thus preventing their aggregation and enhancing their performance for heavy metal cation removal. The adsorption isotherms are well fitted to a Langmuir adsorption model, and the maximal adsorption capacities of Pb(II), Cu(II) and Cd(II) on MnFe2O4@Mn-Co oxide are 481.2, 386.2 and 345.5 mg g(-1), respectively. All the metal ions can be completely removed from the mixed metal ion solutions in a short time. Desorption studies confirm that the adsorbent can be effectively regenerated and reused. PMID:23945878

  2. Novel modified pectin for heavy metal adsorption

    Feng Ting Li; Hong Yang; Yan Zhao; Ran Xu

    2007-01-01

    Modified pectin cross-linked with adipic acid, was synthesized and used for heavy metal removal from wastewater. SEM and FrIR were used to investigate its structure and morphology. The modified pectin had a rough, porous phase covered with carboxy groups, resulting a high adsorption capacity. And at the room temperature, the saturated loading capacity for Pb2+, Cu2+ and Zn2+ reached 1.82 mmol/g, 1.794 mmol/g and 0.964 mmol/g, respectively. The results proved its potential application to remove of the heavy metal.

  3. Evaluation of Factors Influencing Lab-Scale Studies to Determine Heavy Metal Removal by Six Sorbents for Stormwater Treatment

    Maximilian Huber

    2016-02-01

    Full Text Available For the development of decentralized treatment systems for road runoff, the determination of pollutant removal capacities is essential. The aim of this study was to evaluate the impact of boundary conditions on the simultaneous removal of copper, nickel, and zinc by six sorbents used for urban stormwater treatment (i.e., granular activated alumina, anthracite, granular reactivated carbon, granular ferric hydroxide, calcium carbonate, and granular activated lignite. For batch experiments, capacities were determined at initial concentrations within the range of 2.5–180 mg/L with a rotary shaker. Further influences were investigated: the use of a horizontal shaker for concentrations of up to 1080 mg/L, a variation of the initial pH value (5 and 7, and the presence of a buffer. Furthermore, the influences of the filtration process on the capacities were studied. Kinetic experiments were conducted for contact times between 5 min and 120 min. Lab-scale column experiments with inflow concentrations of 2.5 mg/L (copper and nickel and 5.0 mg/L (zinc at an initial pH of 5 and a contact time of 11 min were performed for comparison. Selected experiments were subsequently carried out with changes in initial concentrations and contact time. One result is that it is essential to conduct batch experiments with the metals of interest. The capacities determined by column experiments deviated from batch experiments. Batch experiments under well-defined conditions can be used to evaluate different production batches. Column experiments give a more faithful capacity by considering realistic boundary conditions and should be preferred to determine efficiencies and service lives.

  4. Application of novel consortium TSR for treatment of industrial dye manufacturing effluent with concurrent removal of ADMI, COD, heavy metals and toxicity.

    Patel, Tallika L; Patel, Bhargav C; Kadam, Avinash A; Tipre, Devayani R; Dave, Shailesh R

    2015-01-01

    The present study was aimed towards the effective bio-treatment of actual industrial effluent containing as high as 42,000 mg/L COD (chemical oxygen demand), >28,000 ADMI (American Dye Manufacturers Institute) color value and four heavy metals using indigenous developed bacterial consortium TSR. Mineral salt medium supplemented with as low as 0.02% (w/v) yeast extract and glucose was found to remove 70% ADMI, 69% COD and >99% sorption of heavy metals in 24 h from the effluent by consortium TSR. The biodegradation of effluent was monitored by UV-vis light, HPLC (high performance liquid chromatography), HPTLC (high performance thin layer chromotography) and FTIR (Fourier transform infrared spectroscopy) and showed significant differences in spectra of untreated and treated effluent, confirming degradation of the effluent. Induction of intracellular azoreductase (107%) and NADH-DCIP reductase (128%) in addition to extracellular laccase (489%) indicates the vital role of the consortium TSR in the degradation process. Toxicity study of the effluent using Allium cepa by single cell gel electrophoresis showed detoxification of the effluent. Ninety per cent germination of plant seeds, Triticum aestivum and Phaseolus mungo, was achieved after treatment by consortium TSR in contrast to only 20% and 30% germination of the respective plants in case of untreated effluent. PMID:25945844

  5. Immobilization of 5-aminopyridine-2-tetrazole on cross-linked polystyrene for the preparation of a new adsorbent to remove heavy metal ions from aqueous solution

    Highlights: • Novel chelating resin was prepared using pyridine-2-tetrazole as ligand. • The resin has quite high adsorption capacity for Cu(II), Pb(II) and Hg(II). • The resin shows the different selectivity from the common used IDA resin. • The preparation procedure is a two-step reaction and is easy to carry out. - Abstract: Novel 5-aminopyridine-2-tetrazole-functionalized polystyrene resin (APTZ-PS) was prepared by anchoring 5-aminopyridine-2-carbonitrile onto chloromethylated polystyrene beads (CMPS) and subsequently using the cyano-tetrazole conversion reaction. The APTZ-PS resin was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and specific surface area and pore size analyses. The adsorption experiments of the prepared resin for heavy metal ions were conducted by batch methods. The effects of the experimental conditions, such as pH, contact time and initial metal ion concentration on the adsorption properties of Cu(II), Pb(II) and Hg(II) were investigated. The results showed that the resin possessed perfect adsorption capacities for Cu(II), Pb(II) and Hg(II), and the selectivity was different from the commonly used iminodiacetic acid-chelating resin. The sorption kinetics of the three metal ions followed the pseudo-second-order equation. The adsorption isotherms for Cu(II) and Pb(II) could be better fitted by the Langmuir model than the Freundlich model, whereas the Freundlich model was the best for the Hg(II) ion. Even after five consecutive adsorption–desorption cycles, no obvious change in the adsorption capacity of the resin was found, which implied that the APTZ-PS resin was suitable for the efficient removal of heavy metal ions from aqueous solution

  6. Immobilization of 5-aminopyridine-2-tetrazole on cross-linked polystyrene for the preparation of a new adsorbent to remove heavy metal ions from aqueous solution

    Zhang, Yu; Chen, Youning; Wang, Chaozhan; Wei, Yinmao, E-mail: ymwei@nwu.edu.cn

    2014-07-15

    Highlights: • Novel chelating resin was prepared using pyridine-2-tetrazole as ligand. • The resin has quite high adsorption capacity for Cu(II), Pb(II) and Hg(II). • The resin shows the different selectivity from the common used IDA resin. • The preparation procedure is a two-step reaction and is easy to carry out. - Abstract: Novel 5-aminopyridine-2-tetrazole-functionalized polystyrene resin (APTZ-PS) was prepared by anchoring 5-aminopyridine-2-carbonitrile onto chloromethylated polystyrene beads (CMPS) and subsequently using the cyano-tetrazole conversion reaction. The APTZ-PS resin was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and specific surface area and pore size analyses. The adsorption experiments of the prepared resin for heavy metal ions were conducted by batch methods. The effects of the experimental conditions, such as pH, contact time and initial metal ion concentration on the adsorption properties of Cu(II), Pb(II) and Hg(II) were investigated. The results showed that the resin possessed perfect adsorption capacities for Cu(II), Pb(II) and Hg(II), and the selectivity was different from the commonly used iminodiacetic acid-chelating resin. The sorption kinetics of the three metal ions followed the pseudo-second-order equation. The adsorption isotherms for Cu(II) and Pb(II) could be better fitted by the Langmuir model than the Freundlich model, whereas the Freundlich model was the best for the Hg(II) ion. Even after five consecutive adsorption–desorption cycles, no obvious change in the adsorption capacity of the resin was found, which implied that the APTZ-PS resin was suitable for the efficient removal of heavy metal ions from aqueous solution.

  7. Screening the possibility for removing cadmium and other heavy metals from wastewater sludge and bio-ashes by an electrodialytic method

    Ottosen, Lisbeth M.; Pedersen, Anne Juul; Hansen, Henrik K.;

    2007-01-01

    wastewater sludge and bio-ashes (straw and wood) using an electrodialytic method. The waste products were treated as stirred suspensions. During the remediation the suspension was acidified from water splitting at the anion exchange membrane and the acidification mobilized Cd that was removed to the...... with Cd, and the wood ash had a high initial pH (13.3). The mass of wastewater sludge and bio-ashes decreased during treatment but the concentration of other heavy metals (Pb, Ni, Cu and Zn) was not increased to exceed limiting values in remediated matrix.......Both wastewater sludge and fly ash from combustion of biomass (bio-ash) have traditionally been applied to agricultural land in Denmark. However, Cd concentrations often exceed limiting values. The present study is a preliminary investigation of the possibility for reducing the Cd concentration in...

  8. Removal of chemical oxygen demand, nitrogen, and heavy metals using a sequenced anaerobic-aerobic treatment of landfill leachates at 10-30 degrees C.

    Kalyuzhnyi, Sergey; Gladchenko, Marina; Epov, Andrey; Appanna, Vasu

    2003-01-01

    As a first step of treatment of landfill leachates (total chemical oxygen demand [COD]: 1.43-3.81 g/L; total nitrogen: 90-162 mg/L), performance of laboratory upflow anaerobic sludge bed reactors was investigated under mesophilic (30 degrees C), submesophilic (20 degrees C), and psychrophilic (10 degrees C) conditions. Under hydraulic retention times (HRTs) of about 0.3 d, when the average organic loading rates (OLRs) were about 5 g of COD/(L.d), the total COD removal accounted for 81% (on average) with the effluent concentrations close to the anaerobic biodegradability limit (0.25 g of COD/L) for mesophilic and submesophilic regimes. The psychrophilic treatment conducted under an average HRT of 0.34 d and an average OLR of 4.22 g of COD/(L.d) showed a total COD removal of 47%, giving effluents (0.75 g of COD/L) more suitable for subsequent biologic nitrogen removal. All three anaerobic regimes used for leachate treatment were quite efficient for elimination of heavy metals (Fe, Zn, Cu, Pb, Cd) by concomitant precipitation in the form of insoluble sulfides inside the sludge bed. The application of aerobic/ anoxic biofilter as a sole polishing step for psychrophilic anaerobic effluents was acceptable for elimination of biodegradable COD and nitrogen approaching the current standards for direct discharge of treated wastewater. PMID:12794293

  9. Efficient removal of dyes by a novel magnetic Fe3O4/ZnCr-layered double hydroxide adsorbent from heavy metal wastewater

    Graphical abstract: To purify heavy metal wastewater (pickling waste liquor (PWLA and PWLB) and electroplating wastewater (EPWC and EPWD)), a novel magnetic Fe3O4/ZnCr–LDH material was formed via two-step microwave hydrothermal method (Step 1 and Step 2) and applicable for organic dyes wastewater treatment. Highlights: ► Fe3O4/ZnCr-layered double hydroxide adsorbent was produced from wastewater. ► RSM was successfully applied to the optimization of the preparation conditions. ► The maximum adsorption capacity of MO was found to be 240.16 mg/g. ► The MO adsorption mechanism on MFLA was certified. ► MFLA could be recycled after catalytic regeneration by the oxidation technology. - Abstract: A novel magnetic Fe3O4/ZnCr-layered double hydroxide adsorbent was produced from electroplating wastewater and pickling waste liquor via a two-step microwave hydrothermal method. Adsorption of methyl orange (MO) from water was studied using this material. The effects of three variables have been investigated by a single-factor method. The response surface methodology (RSM) based on Box–Behnken design was successfully applied to the optimization of the preparation conditions. The maximum adsorption capacity of MO was found to be 240.16 mg/g, indicating that this material may be an effective adsorbent. It was shown that 99% of heavy metal ions (Fe2+, Fe3+, Cr3+, and Zn2+) can be effectively removed into precipitates and released far less in the adsorption process. In addition, this material with adsorbed dye can be easily separated by a magnetic field and recycled after catalytic regeneration with advanced oxidation technology. Meanwhile, kinetic models, FTIR spectra and X-ray diffraction pattern were applied to the experimental data to examine uptake mechanism. The boundary layer and intra-particle diffusion played important roles in the adsorption mechanisms.

  10. Heavy metals in linseed

    Klein, H.; Weigert, P.

    1987-11-01

    Linseed offered on the German market was examined for the heavy metals Pb, Cd, Hg, Cr, Cu, Mn, Ni, Zn, as well as As and Se. 490 samples were taken and examined by 31 laboratories of the official food control on the initiative of ALS (Working Group of Experts in Food Chemistry of the Laender and the Federal Health Office). Brown as well as yellow linseed, a new variety, was included in the investigations. The overall results of the investigations show that cadmium contents represent a certain problem from a health point of view. Brown linseed contains an average of 0.380 mg/kg and yellow linseed 0.231 mg/kg cadmium. Considering a weekly linseed intake of 140 g, the potential intake of cadmium corresponds to 10.1% of the WHO value fixed for the time being as tolerable weekly intake for an adult male and 12.2% for an adult female person. The guide value has been fixed at 0.3 mg/kg. Thus, the Cd intakes as related to the WHO value may be reduced by 50% and more.

  11. Heavy Metal Pumps in Plants

    Harper, J.F.

    2000-10-01

    The long term goal of the funded research is to understand how heavy metals are taken up from the soil and translocated throughout the plant. The potential application of this research is to create plants with better heavy metal uptake systems and thereby improve the ability of these plants to help clean up toxic metals from soils. A rate limiting step is using plant for bioremediation is the normally poor capacity of plants to concentrate toxic metals. Our interest in metal ion transport systems includes those for essential mineral nutrients such as molybdenum, copper, iron, manganese, as well as toxic metals such as cerium, mercury, cesium, cadmium, arsenic and selenium. Understanding the pathways by which toxic metals accumulate in plants will enable the engineering of plants to exclude toxic metals and create healthier food sources, or to extract toxic metals from the soil as a strategy to clean up polluted lands and water.

  12. Radiation induced copolymerization of binary monomers system(styrene/acrylic acid) and its application in removal of some heavy metals and dyes from aquatic solutions

    Radiation-induced coploymerization of binary monomer system styrene/acrylic acid (Sty/AAc) using direct radiation technique has been investigated. The appropriate reaction conditions such as solvent, commonomer concentration, commonomer composition and irradiation dose at which the coplymerization process was carried out successfully were selected. The effect of different parameters on the conversion percent of the commonmer into coplomer was studied by gravimetric method. It was found that, using methanol/distilled water as a cosolvent with composition 80/20 wt% enhanced the copolymerization process. The conversion (%) of the commonomer was increased with increasing radiation dose. Some properties of the coplymer such as wate uptake, thermal stability, surface topography were investigated. The improvement in such properties of the prepared coplymers was observed which makes possible uses in some practical applications such as in the removal of some heavy metals and dyes from wastewater. the prepared copolymer has good chemical and thermal stability where as the styrene content lead to increase the swelling behaviour. It was found that the maximum metal uptake by the coplymer is ordered in the sequence of Bp2+>Cu2+>Ni2+. The possibility of the removal of three classes of dyes from aqueous solutions; namely wegocet yellow 4GL (direct yellow 44), congo red (diect red 28). Remacryl blue 3G (basic blue3) and xylene blue *acid blue 7 was studied. It could be concluded that the Sty/AAc copolymer with composition 20/80 wt % can be used as a contrilled water retainer for carrying of some substance in aquatic fields involving environmental treatments. Also, it could be concluded that the most important parameter affecting the swelling behaviour and characteristic of the prepared copolymer are the type of conversion due to chemical treatment, the pH of the medium and coonstituents of the prepared copolymer

  13. Heavy metal removal from MSWI fly ash by electrokinetic remediation coupled with a permeable activated charcoal reactive barrier

    Huang, Tao; Li, Dongwei; Kexiang, Liu; Zhang, Yuewei

    2015-10-01

    This paper presents the investigations into the feasibility of the application of a remediation system that couples electrokinetic remediation (EKR) with the permeable reactive barrier (PRB) concept for municipal solid waste incineration (MSWI) fly ash with activated charcoal as the PRB material. The experimental results of this study showed that the proposed combined method can effectively improve the remediation efficiency and that the addition of the oxalic acid to the PRB media before the coupled system can further enhance the remediation process. In the optimization tests, the maximum removals of Zn, Pb, Cu and Cd were achieved under different experimental conditions. The voltage gradient and processing time were shown to have significant effects on the removal of Cu and Cd, whereas the addition of the oxalic acid had a more significant influence on the removal of Pb. Generally, the processing time is the most significant factor in changing the removal rates of HMs in the enhanced coupled system. In terms of the leaching toxicity, the specimen remediated by ENEKR + PRB showed the lowest leaching value for each HM in the S2 and S3 regions.

  14. Phytoremediation of Heavy Metals in Aqueous Solutions

    Felix Aibuedefe AISIEN; Oluwole FALEYE; Eki Tina AISIEN

    2010-01-01

    One of the major environmental problems is the pollution of water and soil by toxic heavy metals. This study investigated the phytoremediation potential of water hyacinth, for the removal of cadmium (Cd), lead (Pb) and zinc (Zn). Water hyacinths were cultured in bore-hole water, supplemented with 5mg/l of Zn and Pb and 1mg/l of Cd at pH 4.5, 6.8 and 8.5. The plants were separately harvested each week for six weeks. The results showed that removal of these metals from solution was fast especia...

  15. Aqueous heavy metals removal on amine-functionalized Si-MCM-41 and Si-MCM-48

    Ordered mesoporous silica with hexagonal and cubic structure, type MCM-41 and MCM-48 respectively, were synthesized under basic media using pure silica, cetyltrimethylammonium bromide and tetramethylammonium hydroxide, for MCM-41 and tetraethylorthosilica, cetyltrimethylammonium and NaOH for MCM-48. The expanded materials were prepared by post-synthesis method with N-N dimethyldodecylamine (DMDDA) and dodecylamine (DDA). Small angle X-ray diffraction, nitrogen adsorption-desorption measurements, FT-IR and thermogravimetry were used to characterize the samples. The expanded materials were tested for adsorption of Cd2+, Co2+, Cu2+ and Pb2+ in aqueous solution. Aminated materials were found to be fast adsorbents for metallic ions cation with affinity for Cu2+, Pb2+, than for Cd2+ and Co2+ from single solution. In mixed metallic ions cation solutions, competition by the adsorption sites is likely to occur, the adsorption preference is for Cu2+and Pb2+. The kinetic of the reaction is very rapid and follow pseudo-second order and clearly indicated that Langmuir model describe better the for metal ions adsorption on aminated mesoporous material than Freundlich model.

  16. Chemically modified olive stone: a low-cost sorbent for heavy metals and basic dyes removal from aqueous solutions.

    Aziz, Abdellah; Ouali, Mohand Said; Elandaloussi, El Hadj; De Menorval, Louis Charles; Lindheimer, Marc

    2009-04-15

    In the present work, we have investigated the sorption efficiency of treated olive stones (TOS) towards cadmium and safranine removal from their respective aqueous solutions. TOS material was prepared by treatment of olive stones with concentrated sulfuric acid at room temperature followed up by a subsequent neutralization with 0.1 M NaOH aqueous solution. The resulting material has been thoroughly characterized by SEM, energy-dispersive X-ray (EDX), MAS (13)C NMR, FTIR and physicochemical parameters were calculated. The sorption study of TOS at the solid-liquid interface was investigated using kinetics, sorption isotherms, pH effect and thermodynamic parameters. The preliminary results indicate that TOS exhibit a better efficiency in terms of sorption capacities toward the two pollutants (128.2 and 526.3 mg/g for cadmium and safranine, respectively) than those reported so far in the literature. Moreover, the sorption process is ascertained to occur fast enough so that the equilibrium is reached in less than 15 min of contact time. The results found in the course of this study suggest that ion exchange mechanism is the most appropriate mechanism involved in cadmium and safranine removal. Finally, the sorption efficiency of TOS is compared to those of other low-cost sorbents materials yet described in the literature. PMID:18687522

  17. Chemically modified olive stone: A low-cost sorbent for heavy metals and basic dyes removal from aqueous solutions

    In the present work, we have investigated the sorption efficiency of treated olive stones (TOS) towards cadmium and safranine removal from their respective aqueous solutions. TOS material was prepared by treatment of olive stones with concentrated sulfuric acid at room temperature followed up by a subsequent neutralization with 0.1 M NaOH aqueous solution. The resulting material has been thoroughly characterized by SEM, energy-dispersive X-ray (EDX), MAS 13C NMR, FTIR and physicochemical parameters were calculated. The sorption study of TOS at the solid-liquid interface was investigated using kinetics, sorption isotherms, pH effect and thermodynamic parameters. The preliminary results indicate that TOS exhibit a better efficiency in terms of sorption capacities toward the two pollutants (128.2 and 526.3 mg/g for cadmium and safranine, respectively) than those reported so far in the literature. Moreover, the sorption process is ascertained to occur fast enough so that the equilibrium is reached in less than 15 min of contact time. The results found in the course of this study suggest that ion exchange mechanism is the most appropriate mechanism involved in cadmium and safranine removal. Finally, the sorption efficiency of TOS is compared to those of other low-cost sorbents materials yet described in the literature

  18. Screening the possibility for removing cadmium and other heavy metals from wastewater sludge and bio-ashes by an electrodialytic method

    Ottosen, Lisbeth M. [Department of Civil Engineering, Techncial University of Denmark, Building 204, 2800 Lyngby (Denmark)]. E-mail: lo@byg.dtu.dk; Pedersen, Anne J. [Department of Civil Engineering, Techncial University of Denmark, Building 204, 2800 Lyngby (Denmark); Hansen, Henrik K. [Departamento de Procesos Quimicos, Biotecnologicos y Ambientales, Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile); Ribeiro, Alexandra B. [Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Cadencies e Technologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2007-02-25

    Both wastewater sludge and fly ash from combustion of biomass (bio-ash) have traditionally been applied to agricultural land in Denmark. However, Cd concentrations often exceed limiting values. The present study is a preliminary investigation of the possibility for reducing the Cd concentration in wastewater sludge and bio-ashes (straw and wood) using an electrodialytic method. The waste products were treated as stirred suspensions. During the remediation the suspension was acidified from water splitting at the anion exchange membrane and the acidification mobilized Cd that was removed to the electrode compartments. Even though the matrices were very different the remediation was successful in all cases. After treatment the Cd concentration in the ashes allowed for spreading at agricultural land and the limiting concentration of 0.8 mg Cd/kg for the wastewater sludge was almost reached (0.84 and 0.88 mg Cd/kg). The main differences of the waste products influencing the remediation process were: the sludges had a high content of organic particles that were mobilized by electrophoresis and fouled the anion exchange membrane; the straw-ash contained a lot of chloride, which formed anionic complexes with Cd, and the wood ash had a high initial pH (13.3). The mass of wastewater sludge and bio-ashes decreased during treatment but the concentration of other heavy metals (Pb, Ni, Cu and Zn) was not increased to exceed limiting values in remediated matrix.

  19. Screening the possibility for removing cadmium and other heavy metals from wastewater sludge and bio-ashes by an electrodialytic method

    Both wastewater sludge and fly ash from combustion of biomass (bio-ash) have traditionally been applied to agricultural land in Denmark. However, Cd concentrations often exceed limiting values. The present study is a preliminary investigation of the possibility for reducing the Cd concentration in wastewater sludge and bio-ashes (straw and wood) using an electrodialytic method. The waste products were treated as stirred suspensions. During the remediation the suspension was acidified from water splitting at the anion exchange membrane and the acidification mobilized Cd that was removed to the electrode compartments. Even though the matrices were very different the remediation was successful in all cases. After treatment the Cd concentration in the ashes allowed for spreading at agricultural land and the limiting concentration of 0.8 mg Cd/kg for the wastewater sludge was almost reached (0.84 and 0.88 mg Cd/kg). The main differences of the waste products influencing the remediation process were: the sludges had a high content of organic particles that were mobilized by electrophoresis and fouled the anion exchange membrane; the straw-ash contained a lot of chloride, which formed anionic complexes with Cd, and the wood ash had a high initial pH (13.3). The mass of wastewater sludge and bio-ashes decreased during treatment but the concentration of other heavy metals (Pb, Ni, Cu and Zn) was not increased to exceed limiting values in remediated matrix

  20. Separation of heavy metals from aqueous solutions using ''biosorbents''--development of contacting devices for uranium removal

    The objective of this work is to evaluate the utility of a mixed culture of denitrifying bacteria for the separation of uranium from process wastewaters. The selection of this culture was based upon the knowledge that wastewaters generated in a number of nuclear-materials processing operations require treatment to remove both nitrate and uranium. The effects of process variables on the rate of uranium accumulation and equilibrium distribution were studied. Several methods for contacting the biosorbent with aqueous uranium solutions were examined. These included suspended cells or flocs in stirred-tank reactors and films of cells or inert particles in columnar reactors. Results indicating the equilibrium distribution of uranium between the biosorbent and liquid phases are presented as a sorption isotherm. Saturation of the biosorbent with uranium was attained at a biosorbent-phase uranium concentration of about 0.14g uranium/g dry cells. 11 refs

  1. The Fabrication of Bio-ceramsite for the Removal of Heavy Metals and Its Toxicity to Bacteria

    SHI Yan; SUN Ken; QI Xuebin; GAO Qing

    2015-01-01

    Bio-ceramsite technology is one of the most effective technologies in the pretreatment of drinking water. In this work, bio-ceramsite was fabricated byCitrobacter freundii (C. freundii) immobilization on the ceramsite. Thefi ndings of the current study suggest that the bio-ceramites showed biosorption abilities for Cd(II) and Pb(II) and the removal efficiency for Pb(II) is lower than Cd(II). The adsorption mechanism can be attributed to electrostatic attraction and covalent bond. The morphology of the cells changed after the adsorption of Cd(II) and Pb(II) due to the dissociation of the assembly of peptidoglycan and lipopolysaccharide. The fluorescence polarization has shown a significant decrease in membrane fluidity and an increase of permeability of cell membrane. The spectral profi le ofC. freundii suggests the alteration of carbonyl, amide and phosphonic groups on the cell membrane.

  2. Rapid synthesis of titania–silica nanoparticles photocatalyst by a modified sol–gel method for cyanide degradation and heavy metals removal

    Highlights: ► TiO2–SiO2 photocatalyst was prepared by a modified sol–gel technique. ► The modified TiO2–SiO2 catalyst shows remarkable photocatalytic activity. ► Complete degradation of cyanide and removal of Cr, Co, Pb were achieved. ► Catalytic performance depends essentially on catalyst, target and reaction time. - Abstract: Titania–silica (TiO2–SiO2) photocatalyst was prepared by a modified sol–gel technique. Titania sol was firstly synthesized by acid hydrolysis of a TiCl4 precursor instead of titanium alkoxides. The titania sol was further modified with SiO2 to obtain a modified catalyst. The as-prepared TiO2–SiO2 catalyst demonstrated a remarkable photocatalytic activity toward degradation of cyanide and heavy metals removal (Cr(III), Co(II) and Pb(II)). The influence of the preparation parameters; the reaction time, the calcination temperature and time, the [H+]/[Ti] ratio, the pH value and the acid concentration on the structural and chemical properties of the catalyst was investigated in details. The catalytic performance was found to depend essentially on the catalyst and target concentrations and the reaction time. The as-synthesized catalyst was characterized by a variety of techniques including surface area measurement, X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) transmission electron microscopy (TEM) and ultraviolet–visible (UV–vis) spectroscopy measurements. Results of the synthesis and characterization of TiO2–SiO2 catalyst and its photocatalytic performance are presented and thoroughly discussed.

  3. Rapid synthesis of titania-silica nanoparticles photocatalyst by a modified sol-gel method for cyanide degradation and heavy metals removal

    Harraz, Farid A., E-mail: fharraz@cmrdi.sci.eg [Nanostructured Materials and Nanotechnology Division, Central Metallurgical Research and Development Institute (CMRDI), P.O. Box 87 Helwan, Cairo 11421 (Egypt); Abdel-Salam, Omar E. [Faculty of Engineering, Cairo University, Giza (Egypt); Mostafa, Ahlam A. [Aircraft Factory, Helwan (Egypt); Mohamed, Reda M. [Nanostructured Materials and Nanotechnology Division, Central Metallurgical Research and Development Institute (CMRDI), P.O. Box 87 Helwan, Cairo 11421 (Egypt); Faculty of Science, King Abdulaziz University (Saudi Arabia); Hanafy, M. [Faculty of Engineering, Cairo University, Giza (Egypt)

    2013-02-25

    Highlights: Black-Right-Pointing-Pointer TiO{sub 2}-SiO{sub 2} photocatalyst was prepared by a modified sol-gel technique. Black-Right-Pointing-Pointer The modified TiO{sub 2}-SiO{sub 2} catalyst shows remarkable photocatalytic activity. Black-Right-Pointing-Pointer Complete degradation of cyanide and removal of Cr, Co, Pb were achieved. Black-Right-Pointing-Pointer Catalytic performance depends essentially on catalyst, target and reaction time. - Abstract: Titania-silica (TiO{sub 2}-SiO{sub 2}) photocatalyst was prepared by a modified sol-gel technique. Titania sol was firstly synthesized by acid hydrolysis of a TiCl{sub 4} precursor instead of titanium alkoxides. The titania sol was further modified with SiO{sub 2} to obtain a modified catalyst. The as-prepared TiO{sub 2}-SiO{sub 2} catalyst demonstrated a remarkable photocatalytic activity toward degradation of cyanide and heavy metals removal (Cr(III), Co(II) and Pb(II)). The influence of the preparation parameters; the reaction time, the calcination temperature and time, the [H{sup +}]/[Ti] ratio, the pH value and the acid concentration on the structural and chemical properties of the catalyst was investigated in details. The catalytic performance was found to depend essentially on the catalyst and target concentrations and the reaction time. The as-synthesized catalyst was characterized by a variety of techniques including surface area measurement, X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) transmission electron microscopy (TEM) and ultraviolet-visible (UV-vis) spectroscopy measurements. Results of the synthesis and characterization of TiO{sub 2}-SiO{sub 2} catalyst and its photocatalytic performance are presented and thoroughly discussed.

  4. Coupling bioleaching and electrokinetics to remediate heavy metal contaminated soils.

    Huang, Qingyun; Yu, Zhen; Pang, Ya; Wang, Yueqiang; Cai, Zhihong

    2015-04-01

    In this study, bioleaching was coupled with electrokinetics (BE) to remove heavy metals (Cu, Zn, Cr and Pb) from contaminated soil. For comparison, bioleaching (BL), electrokinetics (EK), and the chemical extraction method were also applied alone to remove the metals. The results showed that the BE method removed more heavy metals from the contaminated soil than the BL method or the EK method alone. The BE method was able to achieve metal solubilization rates of more than 70 % for Cu, Zn and Cr and of more than 40 % for Pb. Within the range of low current densities (bioleaching coupled with electrokinetics can effectively remediate heavy metal-contaminated soils and that preliminary tests should be conducted before field operation to detect the lowest current density for the greatest metal removal. PMID:25680933

  5. Removal of Heavy Metals Fe3+, Cu2+, Zn2+, Pb2+, Cr3+ and Cd2+ from Aqueous Solutions by Using Eichhornia Crassipes

    S.A. Shama

    2010-01-01

    Full Text Available The adsorption capacity of Eichhornia Crassipes towards metal ions such as Fe3+, Cu2+, Zn2+, Pb2+, Cr3+ and Cd2+, was studied. The adsorption capacity was investigated by batch experiments. The results showed that the removal percentages increased as the weight of sorbent increased, except for Fe3+ and Zn2+. The effect of contact time was also studied and the results showed that the removal percentages increased as the contact time increased for Cr3+, Zn2+ and Pb2+, but for Fe3+, Cu2+ and Cd2+ the removal decreased. The effect of pH of the solution was also studied and the removal percentages increased as pH increased. Also the effect of the initial concentration of metal ions was studied at four different concentrations (5, 10, 30, 50 mg/L; in case of metal ions (Cu2+, Zn2+ and Cd2+ the removal percentages increased by increasing initial concentration. But, for the other metal ions it decreased by increasing initial concentration over 30 mg/L. The order of increasing removal percentages of metal ions at pH=4.86, initial concentration of metal ions 30 mg/L, and after four hours of shaking was: Cu2+< Cr3+

  6. Efficient removal of dyes by a novel magnetic Fe{sub 3}O{sub 4}/ZnCr-layered double hydroxide adsorbent from heavy metal wastewater

    Chen, Dan; Li, Yang; Zhang, Jia [School of Environmental and Chemical Engineering, Shanghai University, No. 99 Shangda Road, Shanghai 200444 (China); Li, Wenhui [Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China); Zhou, Jizhi; Shao, Li [School of Environmental and Chemical Engineering, Shanghai University, No. 99 Shangda Road, Shanghai 200444 (China); Qian, Guangren, E-mail: grqian@shu.edu.cn [School of Environmental and Chemical Engineering, Shanghai University, No. 99 Shangda Road, Shanghai 200444 (China)

    2012-12-15

    Graphical abstract: To purify heavy metal wastewater (pickling waste liquor (PWL{sub A} and PWL{sub B}) and electroplating wastewater (EPW{sub C} and EPW{sub D})), a novel magnetic Fe{sub 3}O{sub 4}/ZnCr-LDH material was formed via two-step microwave hydrothermal method (Step 1 and Step 2) and applicable for organic dyes wastewater treatment. Highlights: Black-Right-Pointing-Pointer Fe{sub 3}O{sub 4}/ZnCr-layered double hydroxide adsorbent was produced from wastewater. Black-Right-Pointing-Pointer RSM was successfully applied to the optimization of the preparation conditions. Black-Right-Pointing-Pointer The maximum adsorption capacity of MO was found to be 240.16 mg/g. Black-Right-Pointing-Pointer The MO adsorption mechanism on MFLA was certified. Black-Right-Pointing-Pointer MFLA could be recycled after catalytic regeneration by the oxidation technology. - Abstract: A novel magnetic Fe{sub 3}O{sub 4}/ZnCr-layered double hydroxide adsorbent was produced from electroplating wastewater and pickling waste liquor via a two-step microwave hydrothermal method. Adsorption of methyl orange (MO) from water was studied using this material. The effects of three variables have been investigated by a single-factor method. The response surface methodology (RSM) based on Box-Behnken design was successfully applied to the optimization of the preparation conditions. The maximum adsorption capacity of MO was found to be 240.16 mg/g, indicating that this material may be an effective adsorbent. It was shown that 99% of heavy metal ions (Fe{sup 2+}, Fe{sup 3+}, Cr{sup 3+}, and Zn{sup 2+}) can be effectively removed into precipitates and released far less in the adsorption process. In addition, this material with adsorbed dye can be easily separated by a magnetic field and recycled after catalytic regeneration with advanced oxidation technology. Meanwhile, kinetic models, FTIR spectra and X-ray diffraction pattern were applied to the experimental data to examine uptake mechanism. The

  7. Post-crosslinking towards stimuli-responsive sodium alginate beads for the removal of dye and heavy metals.

    Lu, Ting; Xiang, Tao; Huang, Xue-Lian; Li, Cheng; Zhao, Wei-Feng; Zhang, Qian; Zhao, Chang-Sheng

    2015-11-20

    Post-crosslinking as a new strategy to prepare sodium alginate (SA) beads with controllable swelling behavior, pH sensitivity and adsorption capacity was developed by using the solution of glutaraldehyde (GA), acetic acid and hydrochloric acid as the coagulating agent, for which could be used to fabricate polysaccharide beads in a large scale. Fourier transform infrared spectroscopy and thermogravimetric analysis convinced the successful cross-linking of SA by GA. The macro-porous structures of the beads were observed by scanning electron microscopy. Both acetic acid and hydrochloric acid had great effects on the swelling behavior and pH sensitivity of the SA beads. The SA beads could adsorb cationic dye (methylene blue) as high as 572mg/g and other metal ions (Cu(2+), Ag(+) and Fe(3+)). The adsorption processes fitted well with the pseudo-second-order kinetic model and the Freundlich isotherm. The large-scale production of SA beads with tunable properties opens a new route to industrially utilize polysaccharide beads in wastewater treatments, intelligent separation and so on. PMID:26344317

  8. Metal Removal in Wastewater

    Sanchez Roldan, Laura

    2014-01-01

    The aim of this work was to study Copper removal capacity of different algae species and their mixtures from the municipal wastewater. This project was implemented in the greenhouse in the laboratories of Tampere University of Applied Sciences and the wastewater used was the one from the Tampere municipal wastewater treatment plant. Five algae species and three mixtures of them were tested for their Copper removal potential in wastewater in one batch test run. The most efficient algae mixture...

  9. Heavy metal depositions in Germany

    Methods and importance of the measurement of dust precipitation and its metallic components are discussed. Test programs and results of heavy metal measurements in precipitations in Germany are summarized. The focus is on measurements of lead and cadmium. There is a clearly decreasing trend also seen in long-term test programs. The limiting values set in the Clean Air Act were hardly ever exceeded in recent years. (orig.)

  10. Desarrollo de membranas de quitosano y diseño de un equipo para la eliminación de metales pesados del agua Chitosan membrane development and design of equipment for the removal of heavy metals from water

    Jesús Mora Molina

    2012-11-01

    Full Text Available El presente estudio comparó la eficiencia de la filtración con membranas de quitosano 1,75% m/v, entrecruzadas con glutaraldehído (0,08% m/v y sin entrecruzar, para estimar la capacidad de remoción de iones de cadmio, cromo y cobre de disoluciones modelo. Además, se diseñó un equipo de bajo costo para la experimentación con las membranas elaboradas. La finalidad de la investigación era emplear materiales biodegradables para remover metales pesados de aguas, mediante una técnica de bajo consumo energético y, por otra parte, generar soluciones baratas, efectivas y aplicables a problemas específicos. Se elaboraron dos fichas técnicas con información sobre las membranas y se encontró que el cromo fue el metal removido en mayor medida por las membranas entrecruzadas, ajustándose al modelo de isoterma de Freundlich. Sin embargo, no se encontró relación entre el tamaño de poro de las membranas y el grado de entrecruzamiento.A filtration technique with 1,75% m/v chitosan membranes crosslinked with glutaraldehyde (0,08% v/v was used to quantify the removal capacity of chromium, copper and cadmium ions from water. A simple and low cost filtration system was developed to use with prepared membranes.The main goal was to use biodegradable materials for removing heavy metals from water, through a low energy consumption, cheap, and specific method.As a result, two data sheets were prepared for the membranes. It was found out that chromium was the metal with the highest removal from water, by using a crosslinked membrane. Metal adsorption was best adjusted to the Freundlich isotherm model, better than Langmuir isotherm model.However, it was found no correlation between pore size and crosslinking degree.

  11. Electrodialytic remediation of heavy metal polluted soil

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Kirkelund, Gunvor Marie;

    2012-01-01

    Electrodialytic soil remediation is a method for removal of heavy metals. Good results have previously been obtained with both treatment of a stationary, water saturated soil matrix and with remediation of a stirred suspension of soil in water. The two different setups have different uses. The...... stirred setup it is possible to shorten the transport route to few mm and to have a faster and continuous process. The present paper for the first time reports a direct comparison of the two options. The remediation of the stirred suspension showed faster than remediation of the water saturated soil even...... without a short distance between the membranes. The acidification of the suspended soil was fastest and following the mobilization of heavy metals. This may indicate that water splitting at the anion exchange membrane is used more efficiently in the stirred setup....

  12. Heavy metal pollution of industrial cities

    Бувалец, Дарья Юрьевна; Капустин, Алексей Евгеньевич

    2016-01-01

    Heavy metal pollution of cities is an urgent environmental problem. As an example we took Mariupol, on the territory of this city there are two large metallurgical plants. We have studied the heavy metal pollution of urban soils, river water and sediment, which are under the influence of the steel industry. Studies have established the degree and nature of pollution of the Mariupol by various heavy metals. Also, study revealed excess of some heavy metals in the river waters and sediments. We ...

  13. A study of the removal of heavy metals from aqueous solutions by Moringa oleifera seeds and amine-based ligand 1,4-bis[N,N-bis(2-picoyl)amino]butane

    Highlights: ► Materials are effective and selective in simultaneous removal of heavy metal ions. ► Use of composite adsorbent of both materials may result in more effective material. ► Seeds biomass has various functional groups involves in metal removal. ► Attainment of sorption equilibrium is rapid for the seeds biomass. ► Seeds biomass effectiveness is not affected over wide effective pH range. - Abstract: Uptake for lead, copper, cadmium, nickel and manganese from aqueous solution using the Moringa oleifera seeds biomass (MOSB) and amine-based ligand (ABL) was investigated. Experiments on two synthetic multi-solute systems revealed that MOSB performed well in the biosorption and followed the decreasing orders Pb(II) > Cu(II) > Cd(II) > Ni(II) > Mn(II) and Zn(II) > Cu(II) > Ni(II). The general trend of the heavy metal ions uptake by the amine-based ligand followed decreased in the order Mn > Cd > Cu > Ni > Pb, which is the reverse trend for what was observed for MOSB. Comparing the single- and multi-metal solutions, there was no clear effect in the biosorption capacity of MOSB suggesting the presence of sufficient active binding sites for all metal ions studied. The MOSB performance is also not affected by pH in the range 3.5–8.

  14. A study of the removal of heavy metals from aqueous solutions by Moringa oleifera seeds and amine-based ligand 1,4-bis[N,N-bis(2-picoyl)amino]butane

    Obuseng, Veronica; Nareetsile, Florence [Department of Chemistry, University of Botswana, Private Bag UB 00704, Gaborone (Botswana); Kwaambwa, Habauka M., E-mail: hmkwaambwa@yahoo.com [Department of Chemistry, University of Botswana, Private Bag UB 00704, Gaborone (Botswana)

    2012-06-12

    Highlights: Black-Right-Pointing-Pointer Materials are effective and selective in simultaneous removal of heavy metal ions. Black-Right-Pointing-Pointer Use of composite adsorbent of both materials may result in more effective material. Black-Right-Pointing-Pointer Seeds biomass has various functional groups involves in metal removal. Black-Right-Pointing-Pointer Attainment of sorption equilibrium is rapid for the seeds biomass. Black-Right-Pointing-Pointer Seeds biomass effectiveness is not affected over wide effective pH range. - Abstract: Uptake for lead, copper, cadmium, nickel and manganese from aqueous solution using the Moringa oleifera seeds biomass (MOSB) and amine-based ligand (ABL) was investigated. Experiments on two synthetic multi-solute systems revealed that MOSB performed well in the biosorption and followed the decreasing orders Pb(II) > Cu(II) > Cd(II) > Ni(II) > Mn(II) and Zn(II) > Cu(II) > Ni(II). The general trend of the heavy metal ions uptake by the amine-based ligand followed decreased in the order Mn > Cd > Cu > Ni > Pb, which is the reverse trend for what was observed for MOSB. Comparing the single- and multi-metal solutions, there was no clear effect in the biosorption capacity of MOSB suggesting the presence of sufficient active binding sites for all metal ions studied. The MOSB performance is also not affected by pH in the range 3.5-8.

  15. Phytoremediation of Heavy Metals in Aqueous Solutions

    Felix Aibuedefe AISIEN

    2010-12-01

    Full Text Available One of the major environmental problems is the pollution of water and soil by toxic heavy metals. This study investigated the phytoremediation potential of water hyacinth, for the removal of cadmium (Cd, lead (Pb and zinc (Zn. Water hyacinths were cultured in bore-hole water, supplemented with 5mg/l of Zn and Pb and 1mg/l of Cd at pH 4.5, 6.8 and 8.5. The plants were separately harvested each week for six weeks. The results showed that removal of these metals from solution was fast especially in the first two weeks, after which it became gradual till saturation point was reached. The accumulation of Cd and Zn in leaves and roots increased with increase in pH. The highest accumulation was in the roots with metal concentration of 4870mg/kg, 4150mg/kg and 710mg/kg for Zn, Pb and Cd respectively at pH 8.5. The maximum values of bioconcentration factor (BCF for Zn, Pb and Cd were 1674, 1531 and 1479 respectively, suggesting that water hyacinth was good accumulator of Zn, Pb and Cd, and could be used to treat industrial wastewater contaminated with heavy metals such as Zn, Pb and Cd.

  16. Heavy metals in trees and energy crops - a literature review

    This literature review deals with the use of energy crops for cleaning of soils from heavy metals. It also deals with the use of low accumulating energy crops to be used on strongly contaminated soils where a low uptake of heavy metals is preferred, for example on mining deposits. In addition to the efforts to reduce the sources for heavy metal contamination of soils (for example commercial fertilizers and atmospheric deposition) the uptake and removal of heavy metals from the soils by the use of energy crops have recently been discussed as a method for cleaning of soils. Species from the Salix family (willow) have a greater potential for accumulating heavy metals than cereals which makes them interesting for this purpose. The Salix family consists of species with a great genetic variation. This will probably make it possible to find or develop clones with different characteristics suitable for cleaning of contaminated soils as well as for plant covering of soils that are extremely contaminated by heavy metals. In the former case an accumulation of heavy metals in the harvested parts, the shoots, is preferred. In the later case clones that do not accumulate heavy metals and maybe also clones with only root accumulation are preferred. There are also Salix clones with a specific accumulation of heavy metals which makes it possible to clean soils from a toxic metal and at the same time avoid the risk for deficiency of essential metals, for example Zn. The greatest potential to clean soils by the use of energy crops, is when the contamination levels in the soils are low, the areas to clean are large and when the time needed for cleaning is of minor importance. The most suitable soils are those where the metal contamination is located in the top soil layer and where the heavy metal concentrations in the sub soil layer are still low. 58 refs, 8 tabs, 1 fig

  17. Micromycetes sensitiveness to heavy metals

    O. N. Korinovskaya

    2011-07-01

    Full Text Available The sensitivity of 33 micromycete species to nitric compounds of copper, lead, zinc, nickel and cadmium has been determined. Absidia butleri Lendn, Mortierella vanesae Dixon-Stewart, Cunninghamella echinulata Thaxte, Curvularia tuberculata Jain, Cladosporium cladosporiodes (Fresen G. A. de Vries and Fusarium solani (C. Mart. Appel et Wollenw are sensitive to minimal content of the heavy metals (0.75 of maximum permissible concentration (MPC in the growth medium. At the same time Trixoderma longibrachiatiim Rifai, Alternaria alternatа (Fr. Keissl and Penicillium sp. 4 demonstrated moderate growth under maximal concentration (50 MPC. It is determined that minimal content of the heavy metals in the initial stage of influence (up to 48 h promotes growth of only Fusarium oxysporum E. F. Sm. et Swingle, while retards growth of the other species.

  18. Leachability of heavy metals from solidified sludge

    ZHANG HuYuan; WANG Bao; DONG XingLing; FENG Lei; FAN ZhiMing

    2009-01-01

    Solidified sludge undergoes progressive depletion of the alkalinity materials under natural weathering condition and releases out of heavy metals. The leaching of heavy metals from solidified sewage sludge was studied by acid neutralization capacity (ANC) test and flow-through leaching test. The results of ANC test showed that heavy metals release at high concentration when the pH of extract lowers than 6. The disintegration of solidified sludge and the transformation of heavy metals are the main reasons for the resolubilisation of contaminants. Flow-through leaching test indicated that leaching of heavy metals from solidified sludge occurs in a slow way. A mathematical model has been developed to predict the stabilization time of heavy metals in solidified sludge. The research results showed that decreasing hydraulic conductivity is more important than cement addition for controlling the release of heavy metals from solidified sludge.

  19. Mosses accumulate heavy metals from the substrata of coal ash

    Vukojević Vanja; Sabovljević Marko; Jovanović S.

    2005-01-01

    Plants that are able to accumulate and tolerate extraordinarily high concentrations of heavy metals (hyperaccumulators) can be used for phytoremediation (removal of contaminants from soils) or phytomining (growing a crop of plants to harvest the metals). Two moss species, Bryum capillare Hedw. and Ceratodon purpureus Hedw., were tested as potential phytoremedies under in vivo conditions on a coal ash disposal site in the surroundings of Obrenovac (NW Serbia). The content of various heavy meta...

  20. PHYTOEXTRACTION OF HEAVY METALS FROM MINE SOILS USING HYPERACCUMULATOR PLANTS

    Pérez Esteban, Javier; Escolástico, Consuelo; Ruiz Fernández, Juan; Masaguer Rodríguez, Alberto; Moliner Aramendia, Ana María

    2012-01-01

    Phytoextraction is an environmental-friendly and cost-effective technology that uses metal hyperaccumulator plants to remove heavy metals from soils. The metals are absorbed by the roots, transported and accumulated in the aerial parts of the plants, which can be harvested and eliminated. The aim of this work was to study some hyperaccumulator species that could be useful to decontaminate mine soils and also to investigate the bioavailability and uptake of these metals by plants with the addi...

  1. Selective adsorption of heavy and light metals by natural zeolites

    Fosso-Kankeu, Elvis; Reitz, Magdali; Waanders, Frans

    2014-01-01

    Recent studies have shown that zeolite can be applied through an ion-exchange process to remove metals from solutions. In this paper the potential of two zeolites to perform as sorbents for treatment of multi-metal system is investigated. Parameters such as initial metal concentration, contact time, zeolite type and affinity for heavy versus light metals are taken into consideration. All the samples were prepared and characterized by XRD, XRF and FTIR. Evaluating suitable model for the det...

  2. Heavy metal utilization by locally available plants

    Pallewad, Sushma; Mali, R P

    2015-01-01

    The present paper deals with removal of heavy metal namely Copper from polluted water using plant species oscimum and mint. The experiment was divided into 2 groups. Group one as control and group II treated as experimental which received 4ppm of Copper sulphate. In the experimental plants were exposed to 4ppm Cu  for 24 and 48 hrs. And the amount of Cu depleted from water was analyzed. From the experiment it is evident that the Cu from water was utilized by the plants was more during 48 hrs ...

  3. A Novel Permeable Reactive Barrier (PRB) for Simultaneous and Rapid Removal of Heavy Metal and Organic Matter - A Systematic Chemical Speciation Approach on Sustainable Technique for Pallikarani Marshland Remediation

    Selvaraj, A.; Nambi, I. M.

    2014-12-01

    In this study, an innovative technique of ZVI mediated 'coupling of Fenton like oxidation of phenol and Cr(VI) reduction technique' was attempted. The hypothesis is that Fe3+ generated from Cr(VI) reduction process acts as electron acceptor and catalyst for Fenton's Phenol oxidation process. The Fe2+ formed from Fenton reactions can be reused for Cr(VI) reduction. Thus iron can be made to recycle between two reactions, changing back and forth between Fe2+ and Fe3+ forms, makes treatment sustainable.(Fig 1) This approach advances current Fenton like oxidation process by (i)single system removal of heavy metal and organic matter (ii)recycling of iron species; hence no additional iron required (iii)more contaminant removal to ZVI ratio (iv)eliminating sludge related issues. Preliminary batch studies were conducted at different modes i) concurrent removal ii) sequential removal. The sequential removal was found better for in-situ PRB applications. PRB was designed based on kinetic rate slope and half-life time, obtained from primary column study. This PRB has two segments (i)ZVI segment[Cr(VI)] (ii)iron species segment[phenol]. This makes treatment sustainable by (i) having no iron ions in outlet stream (ii)meeting hypothesis and elongates the life span of PRB. Sequential removal of contaminates were tested in pilot scale PRB(Fig 2) and its life span was calculated based on the exhaustion of filling material. Aqueous, sand and iron aliquots were collected at various segments of PRB and analyzed for precipitation and chemical speciation thoroughly (UV spectrometer, XRD, FTIR, electron microscope). Chemical speciation profile eliminates the uncertainties over in-situ PRB's long term performance. Based on the pilot scale PRB study, 'field level PRB wall construction' was suggested to remove heavy metal and organic compounds from Pallikaranai marshland(Fig 3)., which is contaminated with leachate coming from nearby Perungudi dumpsite. This research provides (i

  4. Preparation and characterization of multi-walled carbon nanotubes/chitosan nanocomposite and its application for the removal of heavy metals from aqueous solution

    Research highlights: → Nanocomposite made of multi-walled carbon nanotubes and chitosan was prepared and characterized. → The characterization confirmed the homogenous and well distribution of the MWCNTs within the chitosan matrix. → MWCNTs/chitosan nanocomposite was used for the removal of copper, zinc, cadmium and nickel ions from aqueous solution. → The results showed that nanocomposite could remove successfully most of the metal ions from solution with high efficiency. - Abstract: Multi-walled carbon nanotubes (MWCNTs) were modified with chitosan, and a homogenous nanocomposite was obtained. The morphological properties of the MWCNTs/chitosan nanocomposite were studied with scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and thermal gravimetric analysis (TGA). The morphological results indicate the successful modification and the formation of MWCNTs/chitosan nanocomposites. The MWCNTs/chitosan nanocomposite was packed inside a glass column and used for the removal of copper, zinc, cadmium, and nickel ions from aqueous solution. The MWCNTs/chitosan nanocomposite showed a great efficiency for the removal of the target metal ions from the aqueous solution. The results suggested that this novel MWCNTs/chitosan nanocomposite could be used for different environmental applications.

  5. Bioremediation of heavy metals in liquid media through fungi isolated from contaminated sources.

    Joshi, P K; Swarup, Anand; Maheshwari, Sonu; Kumar, Raman; Singh, Namita

    2011-10-01

    Wastewater particularly from electroplating, paint, leather, metal and tanning industries contain enormous amount of heavy metals. Microorganisms including fungi have been reported to exclude heavy metals from wastewater through bioaccumulation and biosorption at low cost and in eco-friendly way. An attempt was, therefore, made to isolate fungi from sites contaminated with heavy metals for higher tolerance and removal of heavy metals from wastewater. Seventy-six fungal isolates tolerant to heavy metals like Pb, Cd, Cr and Ni were isolated from sewage, sludge and industrial effluents containing heavy metals. Four fungi (Phanerochaete chrysosporium, Aspegillus awamori, Aspergillus flavus, Trichoderma viride) also were included in this study. The majority of the fungal isolates were able to tolerate up to 400 ppm concentration of Pb, Cd, Cr and Ni. The most heavy metal tolerant fungi were studied for removal of heavy metals from liquid media at 50 ppm concentration. Results indicated removal of substantial amount of heavy metals by some of the fungi. With respect to Pb, Cd, Cr and Ni, maximum uptake of 59.67, 16.25, 0.55, and 0.55 mg/g was observed by fungi Pb3 (Aspergillus terreus), Trichoderma viride, Cr8 (Trichoderma longibrachiatum), and isolate Ni27 (A. niger) respectively. This indicated the potential of these fungi as biosorbent for removal of heavy metals from wastewater and industrial effluents containing higher concentration of heavy metals. PMID:23024411

  6. Biosolids and heavy metals in soils

    Silveira Maria Lucia Azevedo

    2003-01-01

    Full Text Available The application of sewage sludge or biosolids on soils has been widespread in agricultural areas. However, depending on their characteristics, they may cause increase in heavy metal concentration of treated soils. In general, domestic biosolids have lower heavy metal contents than industrial ones. Origin and treatment method of biosolids may markedly influence their characteristics. The legislation that controls the levels of heavy metal contents in biosolids and the maximum concentrations in soils is still controversial. In the long-term, heavy metal behavior after the and of biosolid application is still unknown. In soils, heavy metals may be adsorbed via specific or non-specific adsorption reactions. Iron oxides and organic matter are the most important soil constituents retaining heavy metals. The pH, CEC and the presence of competing ions also affect heavy metal adsorption and speciation in soils. In solution, heavy metals can be present either as free-ions or complexed with organic and inorganic ligands. Generally, free-ions are more relevant in environmental pollution studies since they are readily bioavailable. Some computer models can estimate heavy metal activity in solution and their ionic speciation. Thermodynamic data (thermodynamic stability constant, total metal and ligand concentrations are used by the GEOCHEM-PC program. This program allows studying heavy metal behavior in solution and the effect of changes in the conditions, such as pH and ionic strength and the application of organic and inorganic ligands caused by soil fertilization.

  7. Plants Role in Reducing Heavy Metals from Polluted Soil Leachate

    Amouei A.* PhD,

    2015-09-01

    Full Text Available Aims In the past few decades, more attention has been paid to clean up soils polluted with heavy metals by plants. A serious problem in this way is the amount of heavy metals uptake by plants. This study was conducted to evaluate the effectiveness of 3 local plants of Mazandaran province, Iran, in reducing and controlling the soil’s heavy metals. Instrument & Methods The removal amount of three heavy metals (lead, zinc and cadmium by native plants (maize, velvetleaf and wild amaranth was investigated in alkaline (pH=8 and acidic (pH=5 soils and also using three substances such as EDTA, ammonium citrate and phosphate. The concentrations of these metals in leachate were measured by using atomic absorption spectrometry method. Findings Lead, cadmium and zinc levels in leachate in treatments with plants were less than unplanted ones. The concentrations of these metals in the produced leachate of treatments with acidic soils were higher than those with alkaline soils. In the treatments of soil polluted with additives, treatments containing ammonium phosphate and EDTA had the lowest and highest concentrations of heavy metals, respectively. Concentrations of these metals in treatments without plants were higher than those with plants. Conclusion Increasing of soil pH is effective on stabilization of heavy metals in soil. Ammonium phosphate plays an important role in stabilizing and EDTA and ammonium citrate increase the mobility of lead, zinc and cadmium in soil and groundwater.

  8. Removing Heavy Metals in Contaminated Soils by the Organic Acids%有机酸对污染土壤重金属的淋洗效果研究

    易龙生; 王文燕; 陶冶; 刘阳; 温建; 肖娟

    2013-01-01

    以湖南水口山某铅锌选矿厂附近受Zn、Pb、Cu、Cd严重污染土壤为对象,采用振荡淋洗技术,研究了有机酸在不同浓度、时间和液固比条件下对重金属的去除效果.实验结果表明,柠檬酸和酒石酸对重金属具有很好的去除效果,而草酸的去除能力很低;柠檬酸和酒石酸对Cd的去除效果最好,分别为61.5%和55.25%.随着时间的增加,有机酸对重金属的去除效率逐步提高,8h效果最好.柠檬酸和酒石酸对重金属的去除能力均依次为Cd>Zn>Pb>Cu,柠檬酸对重金属的去除率分别为59.5%、49.33%、43.48%、26.25%,酒石酸对重金属去除率分别为58.75%、46.4%、35.86%、34.4%.实验还发现固液比对重金属的淋洗效果影响很小.%Soil washing is considered as one of the most suitable and functional techniques for removing heavy metal.In this paper,contaminated soils by the heavy metals of Pb,Zn,Cu,Cd were collected from the surroundings of a lead-zinc dressing plant in Shuikou Hill,Hunan Province.And the removal effects of the organic acid on heavy metal as a function of concentration,time and liquid-solid ratio by soil washing were studied.The results showed that the citric acid and the tartaric acid had a sound effectiveness,whereas the removal rate of oxalic acid was very low.The Cd removal rate by the citric acid and the tartaric acid were the best,with the removal rate 61.5% and 55.25% respectively.The removal efficiency was gradually improved as a function of time.Best effect was obtained in 8 hours.The removal capacity order of the citric acid and the tartaric acid was:Cd>Zn>Pb>Cu,for the citric acid,the removal rate was 59.5%,49.33%,43.48% and for the tartaricacid,the removal rate was 58.75%,46.4%,35.86% and 34.4%,separately.Meanwhile,it was also found that solid-liquid ratio had little influence on the removal rate of heavy metal.

  9. Heavy Metal Risk Management: Case Analysis

    Kim, Ji Ae; Lee, Seung Ha; Choi, Seung Hyun; Jung, Ki Kyung; Park, Mi Sun; Jeong, Ji Yoon; Hwang, Myung Sil; Yoon, Hae Jung; Choi, Dal Woong

    2012-01-01

    To prepare measures for practical policy utilization and the control of heavy metals, hazard control related institutions by country, present states of control by country, and present states of control by heavy metals were examined. Hazard control cases by heavy metals in various countries were compared and analyzed. In certain countries (e.g., the U.S., the U.K., and Japan), hazardous substances found in foods (e.g., arsenic, lead, cadmium, and mercury) are controlled. In addition, the Joint...

  10. 氨络合法电化学捕集去除城市污泥中重金属的研究%Electrokinetic deposition and removal of heavy metals from sewage sludge enhanced with ammonia complexation

    萧晨霞; 胡勤海; 田耘; 裴毓雯; 张旭

    2014-01-01

    采用自行设计的电动污泥处理装置,以城市污水厂污泥作为试验对象,设置氨水添加比分别为0、0.08、0.10、0.12(V:V,氨水/试样污泥),在恒定直流电压下运行120h,研究氨络合效应与直接利用阳极产酸对污泥中重金属捕集去除效果的影响.结果表明,阳极酸化对污泥中重金属有一定的溶出去除作用;氨水的添加对电动处理过程中污泥 pH 值的降低与电流密度的提高没有阻碍,但能够有效提高污泥中重金属的捕集去除率;当氨水添加比为0.12时,污泥中Zn和Cu的捕集去除效果最佳,分别达91.62%和71.49%.氨水添加比为0.08时,Pb的捕集去除率最佳,达47.85%.氨水的添加对污泥中重金属的形态和迁移性有明显影响,主要表现为稳定形态如残渣态、有机结合态的减少及可交换形态的增加.%The experiment used an in-house designed electrokinetic equipment in order to remove heavy metals from municipal wastewater sludge. Ammonia was added and mixed with four groups of sludge samples at ratios of 0, 0.08, 0.10, 0.12 (V:V, NH3·H2O/sludge sample). The samples were electrolyzed for 120 hours at a constant DC voltage. The effects of anodic acid generation coupled with ammonia complexation on the enhanced removal of heavy metals from sewage sludge was measured. The results indicated that anodic acidification had a moderate removal rate on heavy metals. Although adding ammonia had no impact on pH and electric current density in the electrokinetic process, it enhanced the trapping and removal rate of heavy metals in the sludge. Results further indicated that different amount of ammonia exerted different levels of removal rates under electrokinetic treatment. When ammonia water was added at a ratio of 0.12, removal rates of Zn and Cu were 91.62%and 71.49%, respectively. Optimal remediation was achieved ata ratio of 0.08 for Pb with a removal rate of 47.85%. The enhanced removal effect by adding ammonia was

  11. Effect of ultrasonic treatment on heavy metal decontamination in milk.

    Porova, Nataliya; Botvinnikova, Valentina; Krasulya, Olga; Cherepanov, Pavel; Potoroko, Irina

    2014-11-01

    Ultrasound has been found useful in increasing the efficiency and consumer safety in food processing. Removal of heavy metal (lead, mercury, and arsenic) contamination in milk is extremely important in regions of poor ecological environment - urban areas with heavy motor traffic or well established metallurgical/cement industry. In this communication, we report on the preliminary studies on the application of low frequency (20kHz) ultrasound for heavy metal decontamination of milk without affecting its physical, chemical, and microbiological properties. PMID:24746508

  12. Heavy metal displacement in chelate-irrigated soil during phytoremediation

    Madrid, F.; Liphadzi, M. S.; Kirkham, M. B.

    2003-03-01

    Heavy metals in wastewater sewage sludge (biosolids), applied to land, contaminate soils. Phytoremediation, the use of plants to clean up toxic heavy metals, might remove them. Chelating agents are added to soil to solubilize the metals for enhanced phytoextraction. Yet no studies follow the displacement and leaching of heavy metals in soil with and without roots following solubilization with chelates. The objective of this work was to determine the mobility of heavy metals in biosolids applied to the surface of soil columns (76 cm long; 17 cm diam.) with or without plants (barley; Hordeum vulgare L.). Three weeks after barley was planted, all columns were irrigated with the disodium salt of the chelating agent, EDTA (ethylenediamine tetraacetic acid) (0.5 g/kg soil). Drainage water, soil, and plants were analyzed for heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, Zn). Total concentrations of the heavy metals in all columns at the end of the experiment generally were lower in the top 30 cm of soil with EDTA than without EDTA. The chelate increased concentrations of heavy metals in shoots. With or without plants, the EDTA mobilized Cd, Fe, Mn, Ni, Pb, and Zn, which leached to drainage water. Drainage water from columns without EDTA had concentrations of these heavy metals below detection limits. Only Cu did not leach in the presence of EDTA. Even though roots retarded the movement of Cd, Fe, Mn, Ni, Pb, and Zn through the EDTA-treated soil from 1 d (Cd) to 5 d (Fe), the drainage water from columns with EDTA had concentrations of Cd, Fe, Mn, and Pb that exceeded drinking water standards by 1.3, 500, 620, and 8.6 times, respectively. Because the chelate rendered Cd, Fe, Mn, Ni, Pb, and Zn mobile, it is suggested that the theory for leaching of soluble salts, put forward by Nielsen and associates in 1965, could be applied to control movement of the heavy metals for maximum uptake during chelate-assisted phytoremediation.

  13. Effect of pH control at cathode on the electrokinetic removal of heavy metals from the electroplating sludge%阴极pH控制对电动去除电镀污泥重金属的影响

    张艳杰; 鲁顺保; 彭桂群

    2013-01-01

    采用电动修复装置,选用电镀污泥作为试验材料,试验设计了3个不同pH值的阴极缓冲液处理,施加直流电压32 V,运行7d,研究了不同pH值阴极缓冲液对电镀污泥电动修复过程的影响.结果表明,阴极缓冲液pH值的变化,影响了电动过程中电流大小,pH较低时,电流较大;pH较高时,电流较小.电动修复后,各处理电镀污泥重金属的电动修复效果不同,其中,pH值控制为3时,Ni、Cu、Zn和Cr的去除率分别达到70%、59%、30%和29%,而Pb的去除率在pH值控制为5时去除率达46%.各处理截面重金属浓度较实验前都有不同程度的降低,其中Cu、Pb和Ni在不同污泥截面分布较均匀,而Cr和Zn在各截面分布波动较大.电动修复对各种形态的重金属都有不同程度的去除,对可交换态和铁锰氧化物态的去除效果较差,对碳酸盐结合态和残渣态有明显去除,有机硫化物态去除效果一般.%The effect of pH value of cathode buffer solution on electrokinetic ( EK) remediation efficiency of heavy metals in the electroplating sludge was investigated. In these EK experiments, electrokinetic remediation apparatus was adopted, and the sludge collected from a electroplate factory and seriously polluted by Zn, Cu, Pb, Cr and Ni was used as materials. EK experiments were performed through cathode rinsing using cathode buffer solution with three different pH values and operated for 7 d at 32 V direct current power. The results showed that the pH value of cathode buffer solution changed the current markedly in the EK processes, the lower the pH value, the higher the current. After EK remediation, all experiment systems had different remediation efficiency. The best remediation effect of Ni, Cu, Zn and Cr was observed at pH 3, and the removal rates of Ni,Cu,Zn and Cr were 70% ,59% ,30% and 29% respectively, but the best remediation effect of Pb was observed at pH 5 , and the removal rate of Pb was 46%. In addition

  14. Electrokinetic treatment of an agricultural soil contaminated with heavy metals.

    Figueroa, Arylein; Cameselle, Claudio; Gouveia, Susana; Hansen, Henrik K

    2016-07-28

    The high organic matter content in agricultural soils tends to complex and retain contaminants such as heavy metals. Electrokinetic remediation was tested in an agricultural soil contaminated with Co(+2), Zn(+2), Cd(+2), Cu(+2), Cr(VI), Pb(+2) and Hg(+2). The unenhanced electrokinetic treatment was not able to remove heavy metals from the soil due to the formation of precipitates in the alkaline environment in the soil section close to the cathode. Moreover, the interaction between metals and organic matter probably limited metal transportation under the effect of the electric field. Citric acid and ethylenediaminetetraacetic acid (EDTA) were used in the catholyte as complexing agents in order to enhance the extractability and removal of heavy metals from soil. These complexing agents formed negatively charged complexes that migrated towards the anode. The acid front electrogenerated at the anode favored the dissolution of heavy metals that were transported towards the cathode. The combined effect of the soil pH and the complexing agents resulted in the accumulation of heavy metals in the center of the soil specimen. PMID:27127923

  15. Mosses accumulate heavy metals from the substrata of coal ash

    Vukojević Vanja

    2005-01-01

    Full Text Available Plants that are able to accumulate and tolerate extraordinarily high concentrations of heavy metals (hyperaccumulators can be used for phytoremediation (removal of contaminants from soils or phytomining (growing a crop of plants to harvest the metals. Two moss species, Bryum capillare Hedw. and Ceratodon purpureus Hedw., were tested as potential phytoremedies under in vivo conditions on a coal ash disposal site in the surroundings of Obrenovac (NW Serbia. The content of various heavy metals (iron, manganese zinc, lead, nickel, cadmium, and copper in the mosses and substrata were investigated over a period of three years. Iron and zinc were found to have the highest concentration in the mosses.

  16. Removal of metals by sorghum plants from contaminated land.

    Zhuang, Ping; Shu, Wensheng; Li, Zhian; Liao, Bin; Li, Jintian; Shao, Jingsong

    2009-01-01

    The growth of high biomass crops facilitated by optimal of agronomic practices has been considered as an alternative to phytoremediation of soils contaminated by heavy metals. A field trial was carried out to evaluate the phytoextraction efficiency of heavy metals by three varieties of sweet sorghum (Sorghum biocolor L.), a high biomass energy plant. Ethylene diamine tetraacetate (EDTA), ammonium nitrate (NH4NO3) and ammonium sulphate ((NH4)2SO4) were tested for their abilities to enhance the removal of heavy metals Pb, Cd, Zn, and Cu by sweet sorghum from a contaminated agricultural soil. Sorghum plants always achieved the greatest removal of Pb by leaves and the greatest removal of Cd, Zn and Cu by stems. There was no significant difference among the Keller, Rio and Mray varieties of sweet sorghums in accumulating heavy metals. EDTA treatment was more efficient than ammonium nitrate and ammonium sulphate in promoting Pb accumulation in sweet sorghum from the contaminated agricultural soil. The application of ammonium nitrate and ammonium sulphate increased the accumulation of both Zn and Cd in roots of sorghum plants. Results from this study suggest that cropping of sorghum plants facilitated by agronomic practices may be a sustainable technique for partial decontamination of heavy metal contaminated soils. PMID:19999999

  17. Removal of metals by sorghum plants from contaminated land

    ZHUANG Ping; SHU Wensheng; LI Zhian; LIAO Bin; LI Jintian; SHAO Jingsong

    2009-01-01

    The growth of high biomass crops facilitated by optimization of agronomic practices has been considered as an alternative to phytoremediation of soils contaminated by heavy metals. A field trial was carried out to evaluate the phytoextraction efficiency of heavy metals by three varieties of sweet sorghum (Sorghum biocolor L.), a high biomass energy plant. Ethylene diamine tetraacetate (EDTA), ammonium nitrate (NH4NO3) and ammonium sulphate ((NH4)2SO4) were tested for their abilities to enhance the removal of heavy metals Pb, Cd, Zn, and Cu by sweet sorghum from a contaminated agricultural soil. Sorghum plants always achieved the greatest removal of Pb by leaves and the greatest removal of Cd, Zn and Cu by stems. There was no significant difference among the Keller, Rio and Mray varieties of sweet sorghums in accumulating heavy metals. EDTA treatment was more efficient than ammonium nitrate and ammonium sulphate in promoting Pb accumulation in sweet sorghum from the contaminated agricultural soil. The application of ammonium nitrate and ammonium sulphate increased the accumulation of both Zn and Cd in roots of sorghum plants. Results from this study suggest that cropping of sorghum plants facilitated by agronomic practices may be a sustainable technique for partial decontamination of heavy metal contaminated soils.

  18. Research advances in heavy metal biosorption

    Biosorption of heavy metal has wide applications. The mechanisms of heavy metal biosorption, including complexation, ion exchange, microprecipitation and oxidation reduction, are presented. Thermodynamics and dynamics of biosorption are also discussed. Key factors of influencing biosorption, such as pH values, coexistence ions and temperature are explained. The research directions are explored. (authors)

  19. Heavy Metal, Religiosity, and Suicide Acceptability.

    Stack, Steven

    1998-01-01

    Reports on data taken from the General Social Survey that found a link between "heavy metal" rock fanship and suicide acceptability. Finds that relationship becomes nonsignificant once level of religiosity is controlled. Heavy metal fans are low in religiosity, which contributes to greater suicide acceptability. (Author/JDM)

  20. Heavy metals in packaging : a literature survey

    van Putten EM; IMG

    2011-01-01

    The use of the heavy metals cadmium, mercury, chromium and lead in packaging is forbidden internationally for some years because these substances are harmful to the environment. In 2002 the Dutch national Inspectorate for the Environment determined the presence of heavy metals in packaging for consu

  1. Preparation and characterization of bentonite clays mixture destined to the removal of heavy metals; Preparacao e caracterizacao da mistura de argilas bentoniticas destinadas a remocao de metais pesados

    Almeida Neto, A.F. de; Silva, M.G.C. da, E-mail: ambrosio@feq.unicamp.b [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Fac. de Engenharia Quimica. Dept. de Termofluidodinamica

    2009-07-01

    In this work a mixture was prepared with 50% wt. of the Bofe and Verde-lodo clays. The characterization methods used they were: thermal analyses (TG and DTG), X-ray diffraction, fisissorption of N{sub 2}, scanning electron microscopy and X-ray energy dispersive spectroscopy. The rehearsals of adsorption we accomplished in system of finite bath using as adsorbent the mixture loamy in natura or it mixes calcined. Starting from TG and DTG a thermal treatment was accomplished to 500 deg C of the loamy mixture. Through the results of the copper adsorption, it was verified that mixes loamy it provokes chemical precipitation of the copper while the calcined sample presents amount metal adsorbed around 7.31 mg of copper/g of adsorbent. The value of removal percentage obtained by the calcined sample it was of 63.02%. (author)

  2. Effect of heavy metals on soil fungi

    Sosak-Świderska, Bożena

    2010-05-01

    Fungi constitute a high proportion of the microbial biomass in soil.Being widespread in soil their large surface-to-volume ratio and high metabolic activity, fungi can contribute significantly to heavy metal dynamics in soil. At neutral pH heavy metals in soils tend to be immobilized to precipitation and/or absorption to cation exchange sites of clay minerals. In the acidic soils, metals are more mobile and enter food webs easier. Microbial production of acids and chelating agents can mobilize to toxic metals. Mobilization is often by uptake and intracellular accumulation of the heavy metlas, and in this way, the bioavailability of metals towards other organisms can be more reduced. Fungi were isolated from soils from Upper Silesia in Poland and belonged to widespread genera: Aspergillus, Cladosporium, Penicillium and Trichoderma. Fungi from different taxonomic groups differ greatly in their tolerance to heavy metals. This could be related to their wall structure and chemistry as well as biochemical and physiological characteristics of fungi. Localization of metals in fungal cells was studied using electron microscopy analysis. Metal biosorption in the cell wall can be complex as melanin granules. Fungal vacuoles have an important role in the regulation of the cytosolic concentration of metal ions, and may contribute to heavy metal tolerance.In polluted soils with heavy metals, fungal species composition can be changed and their physiological activity can be changed, too.

  3. Phytoremediation efficiency of pondweed (Potamogeton crispus in removing heavy metals (Cu, Cr, Pb, As and Cd from water of Anzali wetland

    Hajar Norouznia

    2014-09-01

    Full Text Available Plant-based remediation (i.e. phytoremediation is one of the most significant eco-sustainable techniques to cope with devastating consequences of pollutants. In the present study, the potential of a wetland macrophyt (i.e. Potamogeton crispus for the phytoremediation of heavy metals (i.e. Cu, Cr, Pb, As and Cd in the Anzali wetland was evaluated. The results showed that P. crispus tends to accumulate notable amounts of Cu, Cr, Pb, As and Cd according to their assayed concentrations as follows: 8.2 µg g-1 dw, 0.97 µg g-1 dw, 6.04 µg g-1 dw, 2.52 µg g-1 dw and 0.34 µg g-1 dw, respectively. Further accurate perception of the phytoremediation efficiency were conducted using both bioconcentration factor and translocation factor. The average of the highest bioconcentration factors was presented in a descending order as: 2.9×103, 1.9×103, 1.17×103, 0.68×103 and 0.46×103 for the Cu, Cr, Pb, Cd and As, respectively. Based on the results, P. crispus presents high potential to absorb all the alluded metals except for As and partly Cd. Correspondingly, the mean values of translocation factor were reported in the range of 0.41 to 2.24. Eventually, relying on the observed findings, the results support the idea that P. crispus species would be employed as the prospective candidate for the phytoremediation processes in Anzali wetland.

  4. Trace metal removal from combustion gases. Raskasmetallipaeaestoejen vaehentaemismenetelmaet

    Mroueh, U.-M.

    1987-01-15

    This literature survey deals with alternative methods applicable for reducing heavy metal emissions released in fluidized bed combustion or gasification of fossil fuels, such as coal, heavy oil, and municipal and industrial wastes. The elements mercury, cadmium, lead, nickel, vanadium and zinc are the main concern of this study. Increasingly greater attention is being paid to heavy metal emissions from energy production because of the observation in the last few years of the enrichment of some metals into the fine particles. The detectabily range of the existing particulate control devices is usually at this particle size. Most of the investigations aiming at the development of new methods for the reduction of heavy metal emissions are still in the initial stage. Because of the limited information available concerning the problem of heavy metals, this study deals also with some alkali metal removal methods, which possibly can give useful information. The emissions of heavy metals can be reduced, e.g. by binding them to compounds which can be removed from the flue gases. The predominant binding mechanisms are chemical and physical adsorption. Several natural aluminium, calcium and magnesium silicate materials can be used as chemical sorbents. They are also the least expensive of the sorbents. High surface alumina powders are possible physical adsorbents. The reactions between heavy metals and adsorbent can take place in the combustion zone of the fluidized bed reactor or the hot flue gases can be passed through a gas clean-up device, such as granular-bed filter, dry plate scrubber, or adsorbent-smoke reactor.

  5. Poisoning of domestic animals with heavy metals

    Velev Romel; Krleska-Veleva Nataša; Ćupić Vitomir

    2009-01-01

    The term heavy metal refers to a metal that has a relatively high density and is toxic for animal and human organism at low concentrations. Heavy metals are natural components of the Earth's crust. They cannot be degraded or destroyed. To a small extent they enter animal organism via food, drinking water and air. Some heavy metals (e.g cooper, iron, chromium, zinc) are essential in very low concentrations for the survival of all forms of life. These are described as essential tra...

  6. Heavy metal deposition mapping: concentrations and deposition of heavy metals in rural areas of the UK

    Malcolm, Heath; Fowler, David; Crossley, Alan; Kentisbeer, John; Hallsworth, Steve; Lawlor, Alan; Rowland, Phil; Guyatt, Hayley; Beith, Sarah; Thacker, Sarah; Halford, Alan; ROGERS Stuart; Cape, J. Neil; Leeson, Sarah; Harmens, Harry

    2012-01-01

    CEH has been monitoring the concentrations of a range of heavy metals in rural locations across the UK since 2004. This report presents the annual average concentrations and deposition of heavy metals in air and rainfall samples collected from rural locations during 2011 and it reviews the temporal and spatial trends in heavy metal concentrations and deposition between 2004 and 2011. The monitoring network was established to measure the background concentration of a range of heavy meta...

  7. Adsorption Mechanisms of Heavy Metal Ions from Drinking Water by Weakly Basic Anion Exchange Resins

    赵璇; 何仕均; 杨磊

    2002-01-01

    Heavy metal micro-contaminants can be removed from water sources technologies. Weakly basic anion exchange resins offer the best ability to remove trace amounts of heavy metals with high selectivity. This paper discusses how weakly basic resins adsorb heavy metals using two different approaches. The removal of mercury, cadmium, and lead ions is based on the fundamental theory of coordination chemistry. The mechanism is not ion exchange but extractive adsorption of heavy metal salts. However, the marked preferential adsorption of chromate by weakly basic anion exchange can be explained using the traditional theory of ion exchange. A lab-scale study produced positive results for the removal of trace amounts of heavy metal ions from drinking water.

  8. Removal of Heavy Metals from Urban Sewage by Aspergillus Niger and Pseudomonas Fluorescens%黑曲霉、荧光假单胞菌去除污水中重金属试验研究

    李海华; 白国强; 付莹莹; 金艳艳

    2011-01-01

    将黑曲霉和荧光假单胞菌引入到传统的卡鲁塞尔氧化沟工艺模型中,参照规范中氧化沟的水力停留时间,分别选取12、16、20、24、28、32和36 h水力停留时间进行试验,研究了不同水力停留时间2种菌种对重金属Cd、Cr、Pb和Cu的吸附降解规律.对水力停留时间为36 h进行了接种对比试验研究.研究发现接种2种菌种后,当水力停留时间为20 h时,黑曲霉对4种重金属的去除率达到52%~91%.荧光假单胞菌对4种重金属的去除率均达到70%以上,去除效果非常显著,而这个时间参数也正是氧化沟常规的设计参数,由此可以说明,将黑曲霉和荧光假单胞菌引入到城市污水处理工艺中,可以明显提高常规工艺对重金属的吸附降解效率.%Aspergillus niger and Pseudomonas fluorescens were inoculated to the activated sludge in order to improve the removal effectiveness of the oxidation ditch. The comparative experimental study were car ried out when the Hydraulic Retention Time (HRT) was 36 h, and six different HRT of 12 h, 16 h, 20 h, 24 h, 28 h, and 32 h were considered to study the adsorption degradation of Cd, Cr, Pb and Cu by Asper gillus niger and Pseudomonas fluorescens in the oxidation ditch. The result indicated that each of the two strains removal efficiency of the four heavy metals compared with the control group was significantly im proved, and the removal increased with the increasing HRT. When the HRT was 20 h, the removal effi ciency of the four heavy metals by the Aspergillus niger were found to be in the range of 52% to 91%, and the removal efficiency by Pseudomonas fluorescens reached 70%. Most of the heavy metals can be degrad ed in the HRT of 20 h, and this time parameter is exactly the conventional design parameters of oxidation ditch. It can be say that the degradation efficiency of adsorption of heavy metals can be significantly im proved when inoculated with Aspergillus niger and Pseudomonas

  9. Concentration and partitioning of heavy metals in the Scheldt estuary

    Van Alsenoy, V.

    1993-01-01

    The continuous growth of technology has lead to an (uncontrolled) introduction of contaminants into the biosphere. The efforts of removing man-made pollutants from the natural environment have been unable to cope with the increasing amounts of waste materials and growing population. This work studies one group of substances which have a particular lasting effect on the natural balance in aquatic systems; the heavy metals. Trace metals are present in all the abiotic reservoirs of the aquatic s...

  10. Stabilization of heavy metals in sludge ceramsite.

    Xu, G R; Zou, J L; Li, G B

    2010-05-01

    This paper attempts to investigate the stabilization behaviours of heavy metals in ceramsite made from wastewater treatment sludge (WWTS) and drinking-water treatment sludge (DWTS). Leaching tests were conducted to find out the effects of sintering temperature, (Fe(2)O(3) + CaO + MgO)/(SiO(2) + Al(2)O(3)) (defined as F/SA ratios), pH, and oxidative condition. Results show that sintering exhibits good binding capacity for Cd, Cr, Cu, and Pb in ceramsite and leaching contents of heavy metals will not change above 1000 degrees C. The main crystalline phases in ceramsite sintered at 1000 degrees C are kyanite, quartz, Na-Ca feldspars, sillimanite, and enstatite. The main compounds of heavy metals are crocoite, chrome oxide, cadmium silicate, and copper oxide. Leaching contents of Cd, Cu, and Pb increase as the F/SA ratios increase. Heavy metals in ceramsite with variation of F/SA ratios are also in same steady forms, which prove that stronger chemical bonds are formed between these heavy metals and the components. Leaching contents of heavy metals decrease as pH increases and increase as H(2)O(2) concentration increases. The results indicate that when subjected to rigorous leaching conditions, the crystalline structures still exhibit good chemical binding capacity for heavy metals. In conclusion, it is environmentally safe to use ceramsite in civil and construction fields. PMID:20219229

  11. Mechanisms of bacterial metals removal from solids

    The Great Lakes area sediments are contaminated with varying amounts of heavy metals and polychlorinated organic matter. With respect to the bioremediation of metallic contents of these sediments, it was shown that a number of microorganisms exist which can effectively solubilize heavy metals. The basic reaction mechanisms of bioleaching processes were discussed and the effects of semiconductor character of the sulfide substrate explained. A special emphasis was made to comment on INEL's bioremediation capability. 37 refs

  12. Determination of heavy metals in sludge

    The determination of heavy metals in sludge has been investigated. The sludge was separated from waste water sewage by precipitation. The heavy metals analysis has been done using neutron activation (NAA) and x-ray fluorescence. The existence of some metals (Cu, Fe, Ca, K, and Ti) is very important for plants. Otherwise, Pb and Cr had polluted the environment. The results are compared with sheep dung, rubbish and cow dung that are used as natural fertilizer. It is found that the sludge has a low concentration of heavy metals than other. Tow standard samples derived from IAEA have been analyzed with our samples. It is found that our sludge contains some concentration of heavy metals less than the standard. It is found that the increase of Cu and Zn concentration due to uses of pesticides. (author)

  13. Reomoval of Heavy Metals from Aqueous Solutions using Bascteria

    HUANGMin-sheng; PANjing; 等

    2001-01-01

    The accumulation of heavy metals by microbial biomass with high surface area-to-volume ratio holds great potential for heavy metal removal in both soluble and particular forms,especially when the heavy metal concentrations are low(<50mg/L),E.coli and B.Subtilis are effective agents for metal removal.We further investigated the effect of pH,temperature,equilibration time,and pre-treatment reagents on the removal of pH(Ⅱ),Cd(Ⅱ) and Cr(VI) from aqueous solutions by E.Coli and B.subtilis.E.coli and B.subtilis were cultivated for 60 hours,the experimentally determined optimal cultivation time before they were used in metal removal experiments,Under the optimal conditions of pH 6.0,equilibration temperature 30℃ and equilibration time 1 hour,63.39% and 69.90%Cd(Ⅱ) can be removed by E.coli and B.subtilis.Under the optimal conditions of pH5.5,equilibration temperature 30℃ and equliobration time 1 hour,68.51% and 67.36% pB(Ⅱ) can be removed by E.coli and B.subtilis.And under the optimal conditons of pH5.5,equilibration temperature 30℃,and equilibration time 1 hour,60.26% and 54.56% Cr(VI) can be removed by E.coli and B.subtilis.Chemical treatment of cultivated bacteria(0.1mol/L NaOH,0.1mol/L HCl,30% ethanol,and distilled water)affects the efficiency of metal removal by E.coli and B.subtilis,pretreatment of biomass by NaOH enhanced Cd(Ⅱ),Pb(Ⅱ)and Cr(VI) removal,while preteatment by HCl,ethanol and distilled water reduced Ca(Ⅱ) ,Pb(Ⅱ) and Cr(VI) removal,For metal removal from industrial waste discharges,pretreated biomass of E.coli can remove 68.5% of Cd and 58.1% of Cr from solutions,while pretreated biomass of B.subtilis can remove 62.6% of Cd and 57% of Cr from Solutions.

  14. Attrition resistant catalysts and sorbents based on heavy metal poisoned FCC catalysts

    Gangwal, S.; Jothimurugesan, K.

    1999-07-27

    A heavy metal poisoned, spent FCC catalyst is treated by chemically impregnating the poisoned catalyst with a new catalytic metal or metal salt to provide an attrition resistant catalyst or sorbent for a different catalytic or absorption process, such as catalysts for Fischer-Tropsh Synthesis, and sorbents for removal of sulfur gases from fuel gases and flue-gases. The heavy metal contaminated FCC catalyst is directly used as a support for preparing catalysts having new catalytic properties and sorbents having new sorbent properties, without removing or passivating the heavy metals on the spent FCC catalyst as an intermediate step.

  15. Attrition resistant catalysts and sorbents based on heavy metal poisoned FCC catalysts

    Gangwal, Santosh (Cary, NC); Jothimurugesan, Kandaswamy (Hampton, VA)

    1999-01-01

    A heavy metal poisoned, spent FCC catalyst is treated by chemically impregnating the poisoned catalyst with a new catalytic metal or metal salt to provide an attrition resistant catalyst or sorbent for a different catalytic or absorption processes, such as catalysts for Fischer-Tropsh Synthesis, and sorbents for removal of sulfur gasses from fuel gases and flue-gases. The heavy metal contaminated FCC catalyst is directly used as a support for preparing catalysts having new catalytic properties and sorbents having new sorbent properties, without removing or "passivating" the heavy metals on the spent FCC catalyst as an intermediate step.

  16. Ecotoxic heavy metals transformation by bacteria and fungi in aquatic ecosystem.

    Chaturvedi, Amiy Dutt; Pal, Dharm; Penta, Santhosh; Kumar, Awanish

    2015-10-01

    Water is the most important and vital molecule of our planet and covers 75% of earth surface. But it is getting polluted due to high industrial growth. The heavy metals produced by industrial activities are recurrently added to it and considered as dangerous pollutants. Increasing concentration of toxic heavy metals (Pb(2+), Cd(2+), Hg(2+), Ni(2+)) in water is a severe threat for human. Heavy metal contaminated water is highly carcinogenic and poisonous at even relatively low concentrations. When they discharged in water bodies, they dissolve in the water and are distributed in the food chain. Bacteria and fungi are efficient microbes that frequently transform heavy metals and remove toxicity. The application of bacteria and fungi may offer cost benefit in water treatment plants for heavy metal transformation and directly related to public health and environmental safety issues. The heavy metals transformation rate in water is also dependent on the enzymatic capability of microorganisms. By transforming toxic heavy metals microbes sustain aquatic and terrestrial life. Therefore the application of microbiological biomass for heavy metal transformation and removal from aquatic ecosystem is highly significant and striking. This paper reviews the microbial transformation of heavy metal, microbe metal interaction and different approaches for microbial heavy metal remediation from water bodies. PMID:26250544

  17. Heavy metals in drinking water: Occurrences, implications, and future needs in developing countries.

    Chowdhury, Shakhawat; Mazumder, M A Jafar; Al-Attas, Omar; Husain, Tahir

    2016-11-01

    Heavy metals in drinking water pose a threat to human health. Populations are exposed to heavy metals primarily through water consumption, but few heavy metals can bioaccumulate in the human body (e.g., in lipids and the gastrointestinal system) and may induce cancer and other risks. To date, few thousand publications have reported various aspects of heavy metals in drinking water, including the types and quantities of metals in drinking water, their sources, factors affecting their concentrations at exposure points, human exposure, potential risks, and their removal from drinking water. Many developing countries are faced with the challenge of reducing human exposure to heavy metals, mainly due to their limited economic capacities to use advanced technologies for heavy metal removal. This paper aims to review the state of research on heavy metals in drinking water in developing countries; understand their types and variability, sources, exposure, possible health effects, and removal; and analyze the factors contributing to heavy metals in drinking water. This study identifies the current challenges in developing countries, and future research needs to reduce the levels of heavy metals in drinking water. PMID:27355520

  18. Research progress in the removal of heavy metal ions from wastewater by TiO2 photocatalysis%TiO2光催化去除废水中重金属离子的研究进展

    杨永凡; 费学宁

    2012-01-01

    半导体非均相光催化技术在环境治理与净化方面越来越受到人们的重视.概述了半导体TiO2光催化去除废水中重金属离子的机理,从光催化还原角度综合分析了废水中4种主要重金属离子Cr(Ⅵ)、Hg(Ⅱ)、Pb(Ⅱ)、Ag(Ⅰ)的光催化去除特性及其影响因素,进一步加深了对TiO2光催化本质规律的认识,最后讨论了TiO2光催化技术存在的问题和今后的发展趋势.%More and more attention has been paid to environmental governance and purification by semiconductor heterogeneous photocatalysis. An overview is given on the mechanism of TiO2 photocatalytic removal of heavy metal ions. From the angle of photocatalytic reduction,the removing characteristics of photocatalysis of four primary heavy metal ions Cr(Ⅵ)、Hg(Ⅱ)、Pb( Ⅱ)、Ag(Ⅰ) ,and their influencing factors are summarized and analyzed. Further understanding on the essential disciplinarian of TiO2 photocatalysis is obtained. At the end, the problems existing in TiO2 photocatalytic technique and the trend of its future development are discussed.

  19. Remediating sites contaminated with heavy metals

    This article is intended to serve as a reference for decision makers who must choose an approach to remediate sites contaminated with heavy metals. Its purpose is to explain pertinent chemical and physical characteristics of heavy metals, how to use these characteristics to select remedial technologies, and how to interpret and use data from field investigations. Different metal species are typically associated with different industrial processes. The contaminant species behave differently in various media (i.e., groundwater, soils, air), and require different technologies for containment and treatment. We focus on the metals that are used in industries that generate regulated waste. These include steelmaking, paint and pigment manufacturing, metal finishing, leather tanning, papermaking, aluminum anodizing, and battery manufacturing. Heavy metals are also present in refinery wastes as well as in smelting wastes and drilling muds

  20. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    Lima, A.T.; Ottosen, Lisbeth M.; Ribeiro, Alexandra B.

    2012-01-01

    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the...... electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even...... consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by...

  1. Combined Heavy Metal Pollution in Red Soil

    CHENHUAIMAN; ZHENGCHNURONG

    1996-01-01

    The effects of combined heavy metal pollution of red soil on the growth of wetland rice and the transfer of Pb,Cd,Cu and Zn from soil into plants were sudied by greenhouse pot experiment,The results showed that the plantyields were markedly affected by heavy metals,with the exception of Pb,in soils under the experimental conditions,without taking into consideration all the interactions among the elements.The concentrations of the elemets in plants were mainly affected by the specific element added to the soil.The effect of interactions among the heavy metals was very significant either on plant yields or on the concentration of the elements in plants.The risk assessment of a combined pollution by heavy metals in the soil is discussed preliminarily in terms of the relative pollution equivalent.

  2. DECONTAMINATION OF HEAVY METALS WITH BACTERIA

    OBJECTIVES: To discover, improve, understand the mechanisms and use naturally occurring bacteria to decontiminate in situ heavy metals from the soils, sediments and waters to protect human health and the environment. ABSTRACT: Our laboratory (Vesper et al. ...

  3. Heavy metal adsorption by modified oak sawdust: Thermodynamics and kinetics

    This paper describes the adsorption of heavy metal ions from aqueous solutions by oak (Quercus coccifera) sawdust modified by means of HCl treatment. Our study tested the removal of three heavy metals: Cu, Ni, and Cr. The optimum shaking speed, adsorbent mass, contact time, and pH were determined, and adsorption isotherms were obtained using concentrations of the metal ions ranging from 0.1 to 100 mg L-1. The adsorption process follows pseudo-second-order reaction kinetics, as well as Langmuir and D-R adsorption isotherms. The paper discusses the thermodynamic parameters of the adsorption (the Gibbs free energy, entropy, and enthalpy). Our results demonstrate that the adsorption process was spontaneous and endothermic under natural conditions. The maximum removal efficiencies were 93% for Cu(II) at pH 4, 82% for Ni(II) at pH 8, and 84% for Cr(VI) at pH 3

  4. Heavy metals and living systems: An overview

    Reena Singh

    2011-01-01

    Full Text Available Heavy metals are natural constituents of the earth′s crust, but indiscriminate human activities have drastically altered their geochemical cycles and biochemical balance. This results in accumulation of metals in plant parts having secondary metabolites, which is responsible for a particular pharmacological activity. Prolonged exposure to heavy metals such as cadmium, copper, lead, nickel, and zinc can cause deleterious health effects in humans. Molecular understanding of plant metal accumulation has numerous biotechnological implications also, the long term effects of which might not be yet known.

  5. Heavy metals in packaging : a literature survey

    van Putten EM; IMG

    2011-01-01

    The use of the heavy metals cadmium, mercury, chromium and lead in packaging is forbidden internationally for some years because these substances are harmful to the environment. In 2002 the Dutch national Inspectorate for the Environment determined the presence of heavy metals in packaging for consumer products.
    A literature survey was commissioned by the Dutch national Inspectorate for the Environment. Objective was to gather information about actions and checks in other countries o...

  6. Heavy metal screening in compounds feeds

    Tomas Toth

    2015-01-01

    Heavy metals are generally classified as basic groups of pollutants that are now a days found in different environmental compartments. This is quite a large group of contaminants, which have different characteristics, effects on the environment and sources of origin. For environment pose the greatest risks, especially heavy metals produced by anthropogenic activities that adversely affect the health and vitality of organisms and natural environmental conditions. Livestock nutrition is among t...

  7. Phytoremediation potential of Lemna minor L. for heavy metals.

    Bokhari, Syeda Huma; Ahmad, Iftikhar; Mahmood-Ul-Hassan, Muhammad; Mohammad, Ashiq

    2016-01-01

    Phytoremediation potential of L. minor for cadmium (Cd), copper (Cu), lead (Pb), and nickel (Ni) from two different types of effluent in raw form was evaluated in a glass house experiment using hydroponic studies for a period of 31 days. Heavy metals concentration in water and plant sample was analyzed at 3, 10, 17, 24, and 31 day. Removal efficiency, metal uptake and bio-concentration factor were also calculated. Effluents were initially analyzed for physical, chemical and microbiological parameters and results indicated that municipal effluent (ME) was highly contaminated in terms of nutrient and organic load than sewage mixed industrial effluent (SMIE). Results confirmed the accumulation of heavy metals within plant and subsequent decrease in the effluents. Removal efficiency was greater than 80% for all metals and maximum removal was observed for nickel (99%) from SMIE. Accumulation and uptake of lead in dry biomass was significantly higher than other metals. Bio-concentration factors were less than 1000 and maximum BCFs were found for copper (558) and lead (523.1) indicated that plant is a moderate accumulator of both metals. Overall, L. minor showed better performance from SMIE and was more effective in extracting lead than other metals. PMID:26114480

  8. Heavy metals in equine biological components

    Maria Verônica de Souza

    2014-02-01

    Full Text Available The objective of this research was to determine the concentration of heavy metals in the blood (Pb, Ni and Cd, serum (Cu and Zn and hair (Pb, Ni, Cd, Cu and Zn of horses raised in non-industrial and industrial areas (with steel mill, and to verify the possibility to use these data as indicators of environmental pollution. The samples were collected during summer and winter, aiming to verify animal contamination related to environment and season of the year. Copper and Zn contents determined in the serum and Cd and Ni contents obtained in the blood indicated no contamination effects of industries. For some animals, contents of Pb in the blood were higher than those considered acceptable for the species, but without relationship with industrialization and without clinical signs of Pb intoxication. The heavy metals evaluated on the hair of horses in this study were not increased with the presence of industries, but Cu and Cd contents were influenced by the season. The contents of some heavy metals in biological components analyzed were influenced by season sampling; however, serum, blood and hair may not be suitable to indicate differences in environmental contamination between the two contrasting areas. Most part of the heavy metal contents was lower or close to the reference values for horses. Serum, blood and hair components from horses may not be effective as indicators of environmental pollution with heavy metals. Industrialization and seasons have no effects on most part of heavy metals contents from those components.

  9. Plant transporters involved in heavy metal homeostasis

    Dorina Podar

    2010-12-01

    Full Text Available Transition metal ions (predominately manganese, iron, cobalt, nickel, copper and zinc havean array of catalytic and regulatory roles in the growth and development of all living organisms.However, an excess of these metal ions can also be toxic to any life form and therefore every cell andwhole organism needs to maintain the concentration of these essential nutrient metals within a narrowrange: a process known as metal homeostasis. Heavy metal ions are taken up into cells by selectivetransporters and as they cannot be degraded, the “desired” levels of metal ions are achieved by anumber of strategies that involve: chelation, sequestration and export out of the cell. Cation DiffusionFacilitators (CDF is a large family of transporters involved in maintaining the cytosolic metalconcentration. They transport different heavy metal divalent ions, but exhibit main affinity for zinc, ironand manganese. Metal Tolerance Proteins (MTPs are a subfamily of the Cation Diffusion Facilitator (CDFfamily found in plants. There has been much interest in these heavy metal transporters in order toprovide an insight into plant metal homeostasis, which has significant implications in human health andphytoremediation. Although data regarding the CDFs/MTPs mechanism is gathering there is still littleinformation with respect to metal selectivity determinants.

  10. ACTINOMYCETES: TOLERANCE AGAINST HEAVY METALS AND ANTIBIOTICS

    Smriti Singh, Shruti Pandey and Hotam Singh Chaudhary*

    2014-09-01

    Full Text Available Heavy metals can be both, essential as well as toxic for living beings. Micronutrients such as, Co, Fe, Mn have important role to play in living systems whereas, Pb Cd etc. pose harmful effects even at low concentrations. When these heavy metals get accumulated within the tissues of the organisms at various levels of the ecological chain, they cause decrease in the biomass and biological diversity by affecting the growth, morphology and activity of the organisms. Accumulation of heavy metals in soil also causes soil contamination, which can be overcome with the help of bioremediation. A large group of soil bacteria belonging to the Actinomycetes species are exposed to heavy metals in a variety of ways; although, they show resistance to heavy metals. The species of actinomycetes possess resistance for antibiotic synthesis as well. This makes the actinomycetes suitable agents for bioremediation. In this experiment, a total of 20 isolates from Shivpuri region of Madhya Pradesh were tested for the metal tolerance against selected heavy metals. After this, the most tolerant strains were tested to check their antibiotic susceptibility. Metal tolerance was tested by agar well diffusion method and tube dilution method. Out of the 20 isolates, Ash1, Ash 2, Ash 4,Ash 6, Ash 7, Ash 8, Ash 9, Ash 10, Ash 11, Ash 12, Ash 13, Ash 15 were resistant at 10 mM conc. of CuSo4, but their growth was inhibited at higher concentrations of metal salts. Isolates Ash 10, Ash 11, Ash 12, Ash 13, Ash 19, Ash 20 were found to be resistant at 10mM conc. of ZnSO4, but they were also inhibited at higher concentrations. For different concentrations of Pb(CH3COO2 most of the isolates showed same level of tolerance.

  11. Bioaccumulation of heavy metals in fauna from wet detention ponds for stormwater runoff

    Stephansen, Diana; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild;

    2012-01-01

    Stormwater detention ponds remove pollutants e.g. heavy metals and nutrients from stormwater runoff. These pollutants accumulate in the pond sediment and thereby become available for bioaccumulation in fauna living in the ponds. In this study the bioaccumulation was investigated by fauna samples...... from 5 wet detention ponds for analyses of heavy metal contents. Five rural shallow lakes were included in the study to survey the natural occurrence of heavy metals in water-dwelling fauna. Heavy metal concentrations in water-dwelling fauna were generally found higher in wet detention ponds compared...

  12. Phytomining of heavy metals from soil by Croton bonplandianum using phytoremediation technology

    Panchal, K. J.; Dave, B. R.; Parmar, P. P.; Subramanian, R. B.

    2015-12-01

    Metal ions are not only valuable intermediates in metal extraction, but also important raw materials for technical applications. They possess some unique but, identical physical and chemical properties, which make them useful probes of low temperature geochemical reactions. Heavy metals are natural constituents of the earth's crust, but indiscriminate human activities have drastically altered their geochemical cycles and biochemical balance. Metal concentration in soil typically ranges from less than one to as high as 100,000 mg/kg. Heavy metal contaminations of land resources continue to be the focus of numerous environmental studies and attract a great deal of attention worldwide. This is attributed to no--biodegradability and persistence of heavy metals in soils. Prolonged exposure to heavy metals such as cadmium, copper, lead, nickel, and zinc can cause deleterious health effects in humans. Complexation, separation, and removal of metal ions have become increasingly attractive areas of research and have led to new technical developments like phytoremediation that has numerous biotechnological implications of understanding of plant metal accumulation. Croton bonplandianum is newly identified as a potential heavy metal hypreaccumulator. In this study Croton bonplandianum was subjected for in vitro heavy metal accumulation, to explore the accumulation pattern of four heavy metals viz Cadmium, Lead, Nickel and Zinc in various parts of Croton bonplandianum plant parts. It was found that the efficiency of Croton bonplandianum to accumulate heavy metals is Cd>Pb>Zn>Ni. The absorption of these heavy metals in plant parts revealed that the highest translocation of metals from ground to root was ground to be in the order of Pb (1.12) > Zn (0.26) > Ni (0.18) > Cd (0.15). The distribution of Cd in Croton bonplandianum followed the trend Root>Stem>Leaf; with Ni it was Root>Leaf>Stem, while Pb showed leaf>stem>root. Translocation of metals in Croton bonplandianum plant parts

  13. Heavy metal extraction from PCB wastewater treatment sludge by sulfuric acid

    Heavy metals contaminated wastewater sludge is classified as hazardous solid waste and needs to be properly treated to prevent releasing heavy metals to the environment. In this study, the wastewater treatment sludge from a printed circuit board manufacturing plant was treated in a batch reactor by sulfuric acid to remove the contained heavy metals. The effects of sulfuric acid concentration and solid to liquid ratio on the heavy metal removal efficiencies were investigated. The experimental results showed that the total and individual heavy metal removal efficiencies increased with increasing sulfuric acid concentration, but decreased with increasing solid to liquid ratio. A mathematical model was developed to predict the residual sludge weights at varying sulfuric concentrations and solid to liquid ratios. The trivalent heavy metal ions, iron and chromium were more difficult to be removed than the divalent ions, copper, zinc, nickel, and cadmium. For 5 g/L solid to liquid ratio, more than 99.9% of heavy metals can be removed from the sludge by treating with 0.5 M sulfuric acid in 2 h.

  14. Electrokinetic removal of heavy metals in contaminated soil using permeable reactive composite electrodes%可渗透反应复合电极法对土壤重金属的电动去除

    马晋; 罗海宁; 付融冰; 蒋小红; 刘芳; 张长波

    2012-01-01

    摘要将零价铁(Fe°)、沸石等活性材料附着在电极上形成可渗透反应层并构成可渗透反应复合电极,采用不同的复合电极对Cd2+、Ni2+、pb2+和Cu2+等4种阳离子型重金属污染土壤进行了电动力学修复.研究了不同可渗透反应复合电极对土壤pH的控制效果以及对重金属的去除作用.分析了迁移到复合电极中的重金属形态变化.结果表明,复合电极中添加酸、碱性沸石并适时更换,可有效中和、截留阴阳极电解产生的OH和H+,避免或减缓土壤酸碱迁移带的形成,防止重金属离子的过早沉淀及土壤过度酸化,极大提高了重金属的去除率.复合电极中Fe°可将迁移进来的重金属离子进行还原稳定,实现重金属污染物的捕获与固定,与迁移到沸石复合电极中的4种重金属不稳定态相比,“Fe°+沸石”复合电极中重金属不稳定态分别下降了61.4、60.5、61.4、57.1百分点.结果还显示,阴极采用“Fe°+沸石”复合电极并适时进行更换,施加1.5V/cm的直流电压修复10d后,土壤中Cd、Ni、Pb、Cu的总去除率分别为44.5%、41.5%、33.5%和36.7%,且进一步延长修复时间和持续更换电极可获得更为理想的修复效果.%The permeable reactive composite electrodes was established by adhering reactive materials such as zero-valent iron(Fe0) and zeolite on the electrodes to form a permeable reactive layer. The composite electrodes were used for electrokinetic remediation of soil contaminated by Cd2+ , Ni2+ , Pb2+ and Cu2+. The effects of different composite electrodes on pH control and heavy metal removal efficiency were studied, and speciation changes of heavy metals moved onto the electrodes were analyzed. The results showed that with acidic/alkaline zeolite added and timely renewed, the composite electrodes can effectively neutralize and capture H+ and OH- produced from electrolysis of the anode and cathode, avoiding or delaying the formation of

  15. Toxic heavy metals: materials cycle optimization.

    Ayres, R U

    1992-01-01

    Long-term ecological sustainability is incompatible with an open materials cycle. The toxic heavy metals (arsenic, cadmium, chromium, copper, lead, mercury, silver, uranium/plutonium, zinc) exemplify the problem. These metals are being mobilized and dispersed into the environment by industrial activity at a rate far higher than by natural processes. Apart from losses to the environment resulting from mine wastes and primary processing, many of these metals are utilized in products that are in...

  16. Adsorption characteristics of construction waste for heavy metals from urban stormwater runoff☆

    Jianlong Wang; Pingping Zhang; Liqiong Yang; Tao Huang

    2015-01-01

    Stormwater runoff has become an important source of surface water pollution. Bioretention, a low impact devel-opment measure in urban stormwater management, has been proven to be effective in the removal of pol utants from stormwater runoff, with appropriate bioretention media. In this study, construction wastes were selected as bioretention media to remove heavy metals from stormwater runoff. Static and dynamic adsorption batch exper-iments were carried out to investigate the adsorption of heavy metals in simulated stormwater runoff system with construction wastes in different particle sizes. The experimental results show that the pseudo-second-order kinetic model characterizes the adsorption process and the adsorption equilibrium data are wel described by Freundlich isotherm model. The construction wastes used can remove heavy metals from stormwater runoff effectively, with their average removal rates al more than 90%. The particle size of construction wastes greatly influences the equilibrium time, rate and adsorption capacity for heavy metals.

  17. Heavy Metal Poisoning and Cardiovascular Disease

    Eman M. Alissa

    2011-01-01

    Full Text Available Cardiovascular disease (CVD is an increasing world health problem. Traditional risk factors fail to account for all deaths from CVD. It is mainly the environmental, dietary and lifestyle behavioral factors that are the control keys in the progress of this disease. The potential association between chronic heavy metal exposure, like arsenic, lead, cadmium, mercury, and CVD has been less well defined. The mechanism through which heavy metals act to increase cardiovascular risk factors may act still remains unknown, although impaired antioxidants metabolism and oxidative stress may play a role. However, the exact mechanism of CVD induced by heavy metals deserves further investigation either through animal experiments or through molecular and cellular studies. Furthermore, large-scale prospective studies with follow up on general populations using appropriate biomarkers and cardiovascular endpoints might be recommended to identify the factors that predispose to heavy metals toxicity in CVD. In this review, we will give a brief summary of heavy metals homeostasis, followed by a description of the available evidence for their link with CVD and the proposed mechanisms of action by which their toxic effects might be explained. Finally, suspected interactions between genetic, nutritional and environmental factors are discussed.

  18. Development of a low-cost alternative for metal removal from textile wastewater

    Sekomo Birame, C.

    2012-01-01

    Heavy metals (Cd, Cr, Cu, Pb and Zn) found in textile wastewater are removed by a combination of adsorption using volcanic rock as adsorbent, sulfide precipitation and phytoremediation techniques. The integrated system for metal removal combining anaerobic bioreactor as main treatment step and a pol

  19. Selective accumulation of heavy metals by microorganisms

    An investigation of the removal and recovery of uranium from aqueous systems using microbial biomass has been described previously (Nakajima et al. 1982). To establish which microorganisms accumulate the most uranium, we extended our investigation of uranium uptake to 83 species of microorganisms, 32 bacteria, 15 yeasts, 16 fungi and 20 actinomycetes. Of these 83 species of microorganisms tested, extremely high uranium-absorbing ability was found in Pseudomonas stutzeri, Neurospora sitophila, Streptomyces albus and Streptomyces viridochromogenes. The selective accumulation of heavy metal ions by various microorganisms has also been examined. Uranyl, mercury and lead ions were readily accumulated by almost all the species of microorganisms tested. Actinomycetes and fungi differ from many bacteria and most yeasts in their selective accumulation of uranium and mercury. In addition to this fundamental research, uranium recovery was investigated in immobilized Streptomyces albus, a microorganism with high uranium-uptake ability. These immobilized cells adsorbed uranium readily and selectively. The immobilized cells recovered uranium almost quantitatively and almost all uranium absorbed was desorbed with 0.1 M Na2CO3. The dry weight of the free cells decreased by 50% during 5 adsorption-desorption cycles. However, the dry weight of the immobilized cells decreased by only 2% during 5 cycles. These results showed that microbial cells are more stable after immobilization and can be used repeatedly for the process of uranium adsorption-desorption. (orig.)

  20. Adsorption behavior of heavy metals on biomaterials.

    Minamisawa, Mayumi; Minamisawa, Hiroaki; Yoshida, Shoichiro; Takai, Nobuharu

    2004-09-01

    We have investigated adsorption of Cd(II) and Pb(II) at pH 2-6.7 onto the biomaterials chitosan, coffee, green tea, tea, yuzu, aloe, and Japanese coarse tea, and onto the inorganic adsorbents, activated carbon and zeolite. High adsorptive capabilities were observed for all of the biomaterials at pH 4 and 6.7. In the adsorption of Cd(II), blend coffee, tea, green tea, and coarse tea have comparable loading capacities to activated carbon and zeolite. Although activated carbon, zeolite, and chitosan are utilized in a variety of fields such as wastewater treatment, chemical and metallurgical engineering, and analytical chemistry, these adsorbents are costly. On the other hand, processing of the test biomaterials was inexpensive, and all the biomaterials except for chitosan were able to adsorb large amounts of Pb(II) and Cd(II) ions after a convenient pretreatment of washing with water followed by drying. The high adsorption capability of the biomaterials prepared from plant materials is promising in the development of a novel, low-cost adsorbent. From these results, it is concluded that heavy metal removal using biomaterials would be an effective method for the economic treatment of wastewater. The proposed adsorption method was applied to the determination of amounts of Cd(II) and Pb(II) in water samples. PMID:15373400

  1. Development of a treatment process for the removal of heavy metals from raw water for drinking water supply using chelating ion exchange resins. Subproject 1. Final report; Entwicklung der Verfahrenstechnik zur Eliminierung von Schwermetallen aus Rohwaessern zur Trinkwassergewinnung mit chelatbildenden Kationenaustauscherharzen zur technischen Reife. Teilprojekt 1. Abschlussbericht

    Overath, H.; Stetter, D.; Doerdelmann, O.

    2002-07-01

    Chelating cation exchange resins with iminodiacetic acid group (Lewatit TP 207 and Amberlite IRC 748) were tested for the removal of heavy metals in a drinking water treatment plant. The pilot scale filtration experiments were conducted by varying the operating conditions, such as flow rate and feed concentrations. Heavy metal concentrations (nickel, lead, cadmium, zinc) in the feed were adjusted between 20 and 200 {mu}g/L. Different methods for regeneration and conditioning of the resins were developed and investigated. Finally the ion exchange resins were tested according to German health regulations for ion exchangers in drinking water treatment. (orig.)

  2. Community Heavy Metal Exposure, San Francisco, California

    Chavez, A.; Devine, M.; Ho, T.; Zapata, I.; Bissell, M.; Neiss, J.

    2008-12-01

    Heavy metals are natural elements that generally occur in minute concentrations in the earth's crust. While some of these elements, in small quantities, are vital to life, most are harmful in larger doses. Various industrial and agricultural processes can result in dangerously high concentrations of heavy metals in our environment. Consequently, humans can be exposed to unsafe levels of these elements via the air we breathe, the water and food we consume, and the many products we use. During a two week study we collected numerous samples of sediments, water, food, and household items from around the San Francisco Bay Area that represent industrial, agricultural, and urban/residential settings. We analyzed these samples for Mercury (Hg), Lead (Pb), and Arsenic (As). Our goal was to examine the extent of our exposure to heavy metals in our daily lives. We discovered that many of the common foods and materials in our lives have become contaminated with unhealthy concentrations of these metals. Of our food samples, many exceeded the EPA's Maximum Contaminant Levels (MCL) set for each metal. Meats (fish, chicken, and beef) had higher amounts of each metal than did non-meat items. Heavy metals were also prevalent in varying concentrations in the environment. While many of our samples exceeded the EPA's Sediment Screening Level (SSL) for As, only two other samples surpassed the SSL set for Pb, and zero of our samples exceeded the SSL for Hg. Because of the serious health effects that can result from over-exposure to heavy metals, the information obtained in this study should be used to influence our future dietary and recreational habits.

  3. Heavy metal speciation in the composting process.

    Greenway, Gillian M; Song, Qi Jun

    2002-04-01

    Composting is one of the more efficient and environment friendly methods of solid waste disposal and has many advantages when compared with landfill disposal on which the UK and Ireland are currently heavily dependent. Composting is a very complicated process involving intensive microbial activity and the detailed mechanisms of the process have yet to be fully understood. Metal speciation information can provide an insight into the metal-microbial interaction and would help in the evaluation of the quality of compost. This would facilitate the exploitation of composts in remediation of heavy metal contaminated land. In this work a systematic approach to metal speciation in compost has been taken by applying the three-step method for operationally defined metal speciation of soils and sediments, developed by the European Commission's Standards, Measurement and Testing Programme to monitor the change in metal speciation with time (up to 106 days) for four different waste composting processes. The results have shown that in general metals become less available for the first extraction step as the composting process proceeds. This implies that composting tends to redistribute the metals from more labile forms to more fixed forms which may explain why the application of composts could be useful for with heavy metal contaminated land. There are exceptions to this trend and in some cases, certain metals appear to behave differently depending on the source of the compost. PMID:11993774

  4. Quantification of uncertainty in modelled partitioning and removal of heavy metals (Cu, Zn) in a stormwater retention pond and a biofilter

    Vezzaro, Luca; Eriksson, Eva; Ledin, Anna;

    2012-01-01

    treatment models. This study identified the major sources of uncertainty when estimating the removal of copper and zinc in a retention pond and a biofilter by using a conceptual dynamic model which estimates MP partitioning between the dissolved and particulate phases as well as environmental fate based on......-driven evapotranspiration, underestimation of sorption and neglect of oversaturation with respect to minerals/salts. The results of this study however illustrate the potential for the application of conceptual dynamic fate models base on substanceinherent properties, in combination with available datasets and statistical...

  5. EXTRACTION, RECOVERY, AND BIOSTABILITY OF EDTA FOR REMEDIATION OF HEAVY METAL-CONTAMINATED SOIL. (R825549C052)

    Chelation removal of heavy metals from contaminated soil is seen as a viable remediation technique. A useful chelating agent should be strong, reusable, and biostable during metal extraction and recovery operations. This work tested the extraction, recovery, and biostability o...

  6. Suppressing Heavy Metal Leaching through Ball Milling of Fly Ash

    Zhiliang Chen

    2016-07-01

    Full Text Available Ball milling is investigated as a method of reducing the leaching concentration (often termed stablilization of heavy metals in municipal solid waste incineration (MSWI fly ash. Three heavy metals (Cu, Cr, Pb loose much of their solubility in leachate by treating fly ash in a planetary ball mill, in which collisions between balls and fly ash drive various physical processes, as well as chemical reactions. The efficiency of stabilization is evaluated by analysing heavy metals in the leachable fraction from treated fly ash. Ball milling reduces the leaching concentration of Cu, Cr, and Pb, and water washing effectively promotes stabilization efficiency by removing soluble salts. Size distribution and morphology of particles were analysed by laser particle diameter analysis and scanning electron microscopy. X-ray diffraction analysis reveals significant reduction of the crystallinity of fly ash by milling. Fly ash particles can be activated through this ball milling, leading to a significant decrease in particle size, a rise in its BET-surface, and turning basic crystals therein into amorphous structures. The dissolution rate of acid buffering materials present in activated particles is enhanced, resulting in a rising pH value of the leachate, reducing the leaching out of some heavy metals.

  7. Heavy metal pollutant tolerance of Azolla pinnata

    Sarkar, A.; Jana, S.

    1986-01-01

    The effects of Hg, As, Pb, Cu, Cd, and Cr (1,2 and 5 mg L/sup -1/ each) on Azolla pinnata R. Br. were analyzed. The treatments (2 and 5 mg L/sup -1/) of the heavy metal pollutants decreased Hill activity, chlorophyll, protein and dry wt, and increased tissue permeability over control values. The effects were most pronounced with the treatment of 5 mg L/sup -1/. The harmful effects of the metals were, in general, found by the treatments in the order: Cd > Hg > Cu > As > Pb > Cr. There was no significant change in these parameters at 1 mg L/sup -1/ of the metals over control. Thus Azolla pinnata shows tolerance to the heavy metals tested up to 1 mg L/sup -1/ each.

  8. Esterase resistant to inactivation by heavy metals

    El, Dorry Hamza

    2014-09-25

    EstATII is an esterase that a halotolerant, thermophilic and resistant to a spectrum of heavy metals including toxic concentration of metals. It was isolated from the lowest convective layer of the Atlantis II Red Sea brine pool. The Atlantis II brine pool is an extreme environment that possesses multiple harsh conditions such as; high temperature, salinity, pH and high concentration of metals, including toxic heavy metals. A fosmid metagenomic library using DNA isolated from the lowest convective layer this pool was used to identify EstATII. Polynucleotides encoding EstATII and similar esterases are disclosed and can be used to make EstATII. EstATII or compositions or apparatuses that contain it may be used in various processes employing lipases/esterases especially when these processes are performed under harsh conditions that inactivate other kinds of lipases or esterases.

  9. Removal of metals in constructed wetlands

    Crites, R.W.; Watson, R.C.; Williams, C.R.

    1996-12-31

    Trace metals are difficult to remove from municipal wastewater by conventional wastewater treatment methods. Constructed wetlands have the potential to trap and remove metals from the water column. Long term removal is expected to occur by accumulation and burial in the plant detritus in a manner similar to the removal of phosphorus. Few data are available in the literature on removal of metals by constructed wetlands. A free water surface constructed wetland at Sacramento Regional Wastewater Treatment Plant treating secondary municipal effluent has been operating since the spring of 1994. Removal data for 13 metals are presented for the period from August 1994 to May 1995. About 3,785 m{sup 3}/d (1 mgd) of pure oxygen activated sludge effluent, disinfected using UV light, is further treated through a 8 ha (20 acre) constructed wetlands Ten separate, parallel treatment cells are available to demonstrate the effects of detention time, vegetation management, and application frequency on the removal of metals, organics and ammonia. Detention time can be varied from 3 to 13 days by varying the flow and the water depth. The vegetation, primarily bulrush with some cattails, will be managed by different techniques to minimize mosquito production. Application frequency varies from continuous flow to batch flow (1 to 2 days of loading with 1 day of discharge).

  10. Removal of gadolinium nitrate from heavy water

    Wilde, E.W.

    2000-03-22

    Work was conducted to develop a cost-effective process to purify 181 55-gallon drums containing spent heavy water moderator (D2O) contaminated with high concentrations of gadolinium nitrate, a chemical used as a neutron poison during former nuclear reactor operations at the Savannah River Site (SRS). These drums also contain low level radioactive contamination, including tritium, which complicates treatment options. Presently, the drums of degraded moderator are being stored on site. It was suggested that a process utilizing biological mechanisms could potentially lower the total cost of heavy water purification by allowing the use of smaller equipment with less product loss and a reduction in the quantity of secondary waste materials produced by the current baseline process (ion exchange).

  11. A Review of Heavy Metals Immunoassay Detection

    Bing Lv; Qiong Jiang; Cheng Zhu

    2015-01-01

    Contamination of heavy metals in soil has been a significant problem, which resulted in food pollution and diseases through bioaccumulation. Traditional methods utilized to determined content of metal ions are time-cost, expensive and laboratorial. Since the introduction of antibody against In-EDTA, immunoassay has been developing for several decades. It filled in the blank of determination in situ with lower price and a short period. In this study, we mainly presented the research process of...

  12. Heavy metal mining using microbes.

    Rawlings, Douglas E

    2002-01-01

    The use of acidiphilic, chemolithotrophic iron- and sulfur-oxidizing microbes in processes to recover metals from certain types of copper, uranium, and gold-bearing minerals or mineral concentrates is now well established. During these processes insoluble metal sulfides are oxidized to soluble metal sulfates. Mineral decomposition is believed to be mostly due to chemical attack by ferric iron, with the main role of the microorganisms being to reoxidize the resultant ferrous iron back to ferric iron. Currently operating industrial biomining processes have used bacteria that grow optimally from ambient to 50 degrees C, but thermophilic microbes have been isolated that have the potential to enable mineral biooxidation to be carried out at temperatures of 80 degrees C or higher. The development of higher-temperature processes will extend the variety of minerals that can be commercially processed. PMID:12142493

  13. Development of active barriers for removing heavy metals from mine water: Freiberg colliery, Sachsen; Entwicklung aktiver Barrieren fuer die Entfernung von Schwermetallen aus Grubenwaessern am Beispiel der Freiberger Grube, Sachsen

    Zoumis, T.

    2003-07-01

    Mine water treatment is costly, difficult, and requires extensive surface installations. The author explains the development of geochemical ('active') barriers of low-cost materials. The materials investigated were industrial residues (red sludge, fly ash, tinder residues, porous concrete residues), natural materials (bark, zeolite, bentonite, hydroxyl apatite), and commercial products (GEH, Ratio Pur MF-S). Investigations focused on density, specific surface, grain size, and acid neutralization capacity. In the final stage, experiments were made on heavy metal removal from a model water. [German] Einen grossen Anteil an der Schwermetallbelastung in Fluessen haben toxische Abwaesser aus Bergbaugebieten (Grubenwaesser). Die Moeglichkeit der Behandlung sind sehr aufwendig, kostenintensiv und nur 'ueber Tage' durchfuehrbar. Die vorliegende Arbeit erlaeutert die Behandlung von Grubenwaessern mit geochemischen ('aktiven') Barrieren. Es werden aktive Barrieren entwickelt, die in einen Schacht eingebracht werden koennen, um eine Schwermetallausbreitung zu unterbinden. In diesem Zusammenhang werden kostenguenstige Materialien untersucht, die Schadstoffe durch chemische und/oder physikalische Mechanismen aus Wasser entfernen koennen. Untersucht wurden industrielle Reststoffe (Rotschlamm, Flugasche, Zunderrueckstaende, Porenbetonabfall), natuerliche Materialien (Baumrinde, Zeolith, Bentonit, Hydroxylapatit) und kommerzielle Produkte (GEH, Ratio Pur MF-S). Die Materialien werden hinsichtlich der Dichte, der spezifischen Oberflaeche, der Korngroesse und der Saeureneutralisationskapazitaet charakterisiert. Anschliessend wurden Versuche zur Schwermetallentfernung aus einem Modellwasser durchgefuehrt. (orig.)

  14. Preparation of silica-supported porous sorbent for heavy metal ions removal in wastewater treatment by organic-inorganic hybridization combined with sucrose and polyethylene glycol imprinting

    A new porous sorbent for wastewater treatment of metal ions was synthesized by covalent grafting of molecularly imprinted organic-inorganic hybrid on silica gel. With sucrose and polyethylene glycol 4000 (PEG 4000) being synergic imprinting molecules, covalent surface coating on silica gel was achieved by using polysaccharide-incorporated sol-gel process starting from the functional biopolymer, chitosan and an inorganic epoxy-precursor, gamma-glycidoxypropyltrimethoxysiloxane (GPTMS) at room temperature. The prepared porous sorbent was characterized by using simultaneous thermogravimetry and differential scanning calorimeter (TG/DSC), scanning electron microscopy (SEM), nitrogen adsorption porosimetry measurement and X-ray diffraction (XRD). Copper ion, Cu2+, was chosen as the model metal ion to evaluate the effectiveness of the new biosorbent in wastewater treatment. The influence of epoxy-siloxane dose, buffer pH and co-existed ions on Cu2+ adsorption was assessed through batch experiments. The imprinted composite sorbent offered a fast kinetics for the adsorption of Cu2+. The uptake capacity of the sorbent imprinted by two pore-building components was higher than those imprinted with only a single component. The dynamic adsorption in column underwent a good elimination of Cu2+ in treating electric plating wastewater. The prepared composite sorbent exhibited high reusability. Easy preparation of the described porous composite sorbent, absence of organic solvents, cost-effectiveness and high stability make this approach attractive in biosorption

  15. Application of Hydrothermal and Non-Hydrothermal TiO2 Nanoporous Materials as New Adsorbents for Removal of Heavy Metal Ions from Aqueous System

    Mansoor Anbia

    2016-06-01

    Full Text Available Hydrothermal and non-hydrothermal spherical TiO2 nanoporous with crystalline framework were prepared by sol-gel method. The Crystalline structures, morphologies and surface texturing of materials were determined by X-ray diffraction (XRD, scanning electron microscopy (SEM and N2 adsorption-desorption isotherms. The Hydrothermal spherical TiO2 nanoporous was found to have a narrow and strong pore size distribution peaks with average of 37.8 Å and pore volume of 0.41 cm3/g and the (Brunauer–Emmett–TellerBET specific surface area of 365 m2/g. Hydrothermal and non-hydrothermal spherical TiO2 nanoporous have been used as adsorbent to study of the adsorption behavior of Pb(II, Co(II and Ni(II ions from aqueous system in a batch system. Effect of equilibrium time on adsorption Pb(II, Co(II and Ni(II ions on these adsorbent was studied The results show that the shaking time 0.5 to 10h has no serious effect on the percentage of ions removal, and the adsorption is fast in all cases. The maximum uptake capacities of Hydrothermal and non-hydrothermal spherical TiO2 nanoporous was calculated. Both hydrothermal and non-hydrothermal TiO2 nanoporous materials were found to have very good potential as new adsorbents in removal of these ions. In batch systems the maximum uptake capacities of Pb(II, Ni(II and Co(II on the hydrothermal and non-hydrothermal TiO2 nanoporous materials was Co(II > Pb(II > Ni(II and Co(II > Ni(II > Pb(II, respectively.

  16. Heavy metals and related trace elements

    A review is given of heavy metals and related trace elements in the aquatic environment. Other reviews and bibliographies are cited, dealing with the metabolism and transport of metal ions and with the toxic effects of stable and radioactive trace metals on aquatic organisms. The sources of trace elements in natural waters are discussed. It is suggested that atmospheric inputs of several trace metals comprise sizable fractions of total inputs to the Great Lakes and continental shelf waters. Information on stack emissions of trace elements from a coal-fired steam plant was used to estimate the likely range of air concentrations and inputs to a forested watershed in Tennessee. Some basic concepts of cycling of elements through aquatic communities were examined, such as the Pb, Mn and Zn concentrations in sediment and estuarine plants and animals colonizing dredge-spoil disposal areas. The use of plants as biological indicators of trace element contamination was outlined, as well as bioaccumulation in aquatic fauna. The effects of environmental factors on the kinetics of element exchange were noted, for example the influx rates of Cs 137 in tubificid worms, and Co 60 and Zn 65 in shrimp were shown to be temperature dependent. The toxicity of heavy metals on aquatic fauna was discussed, such as the histopathological lesions in the kidney and liver of fishes caused by heavy metals, and the effects of Hg and Cu on the olfactory response of rainbow trout

  17. Electrodialytic removal of heavy metals and chloride from municipal solid waste incineration fly ash and air pollution control residue in suspension - test of a new two compartment experimental cell

    Kirkelund, Gunvor Marie; Magro, Cátia; Guedes, Paula;

    2015-01-01

    MSWI residues in for instance concrete, the aim of remediation should be reduction of the heavy metal leaching, while at the same time keeping the alkaline pH, so the residue can replace cement. In this study a MSWI residues were subjected to electrodialytic remediation under various experimental......Municipal solid waste incineration (MSWI) residues such as fly ash and air pollution control (APC) residues are classified as hazardous waste and disposed of, although they contain potential resources. The most problematic elements in MSWI residues are leachable heavy metals and salts. For reuse of...... compared to the initial heavy metal leaching except when the pH was reduced to a level below 8 for the fly ash. On the other hand, Cr leaching increased by the electrodialytic treatment. Cl leaching from the MSWI residues was less dependent on experimental conditions and was reduced in all experiments...

  18. Electrodialytic decontamination of heavy metal polluted soil

    Ottosen, Lisbeth M.; Hansen, Henrik K.; Karlsmose, Bodil;

    1996-01-01

    Electrodialytic remediation of heavy metal polluted soil is a newly developed method, which combines the electrokinetic mevement of ions in soil with the principle of electrodialytis. The method has been proven to work in laboratory scale and at present two types of pilot plant tests are made....

  19. Superoxide dismutases of heavy metal resistant streptomycetes.

    Schmidt, Astrid; Schmidt, André; Haferburg, Götz; Kothe, Erika

    2007-02-01

    Heavy metal tolerant and resistant strains of streptomycetes isolated from a former uranium mining site were screened for their superoxide dismutase expression. From the strains tolerating high concentrations of different heavy metals, one was selected for its tolerance of concentrations of heavy metals (Ni, Cu, Cd, Cr, Mn, Zn, Fe). This strain, Streptomyces acidiscabies E13, was chosen for the purpose of superoxide dismutase analysis. Gel electrophoresis and activity staining revealed only one each of a nickel (NiSOD) and an iron (FeZnSOD) containing superoxide dismutase as shown by differential enzymatic repression studies. The gene for nickel containing superoxide dismutase, sodN, was cloned and sequenced from this strain. The genomic sequence shows 92.7% nucleotide identity and 96.1% amino acid identity to sodN of S. coelicolor. Expression can be activated by nickel as well as other heavy metals and active enzyme is produced in media lacking nickel but containing copper, iron or zinc. Thus, the selected strain is well suited for further characterization of the enzyme encoded by sodN. PMID:17304620

  20. Electrodialytic decontamination of heavy metal polluted soil

    Ottosen, Lisbeth M.; Hansen, Henrik K.; Karlsmose, Bodil; Villumsen, Arne

    Electrodialytic remediation of heavy metal polluted soil is a newly developed method, which combines the electrokinetic mevement of ions in soil with the principle of electrodialytis. The method has been proven to work in laboratory scale and at present two types of pilot plant tests are made....

  1. Atmospheric heavy metal deposition in Europe

    Ruehling, Aa. (ed.)

    1994-03-01

    Atmospheric heavy metal deposition in Europe including 21 countries was monitored by the moss technique. The objectives of the project were to characterise qualitatively and quantitatively the regional atmospheric deposition pattern of heavy metals in background areas in Europe, to indicat the location of important heavy metal pollution sources. Samples of mainly the moss species Pleurozium schreberi, Hylocomium splendens and Hypnum cupresiforme were collected during the summertime 1990. The total concentrations of arsenic, cadmium, chromium, copper, iron, lead, nickel, vanadium and zinc were determined and the results presented in the form of coloured contour maps of Europe. In the Nordic countries and adjacent areas the regional deposition pattern of all the metals shows a decreasing gradient from relatively high values in the southern parts of Scandinavia to low values towards the North. A significant decreas. in the concentrations of most elements was found in this area during the last 10-20 years. Important local enhancements of the concentrations in moss were found superimposed on the regional background pattern, especially at the great smelting combinates in Nikel, Zapolyarnyj and Monchegorsk in Russia in the western part of the Kola Peninsula. Higher levels of metals are found at Mazeikiai (oil refinery) in Lithuania, close to Liepaja (steel mill) and Riga in Latvia and in the industrial north-eastern area of Estonia and adjacent area of Russia. Higher levels of metals were found in the metropolitan area of St. Petersburg. In Central Europe, Poland, and the Czech Republic have numerous sources of air pollution, as well as area in Germany. The Netherlands is particularly affected by pollution from Belgium and western Germany. The Environmental Monitoring and Data Group in the Nordic Countries would like the next survey of heavy metals, including mercury, in moss to take place in 1995. (EG) (45 refs.)

  2. Metabolic Demands of Heavy Metal Drumming

    Bryan Romero

    2016-07-01

    Full Text Available Background: The drum set involves dynamic movement of all four limbs. Motor control studies have been done on drum set playing, yet not much is known about the physiological responses to this activity. Even less is known about heavy metal drumming. Aims: The purpose of this study was to determine metabolic responses and demands of heavy metal drumming. Methods: Five semi-professional male drummers (mean ± SD age = 27.4 ± 2.6 y, height = 177.2 ± 3.8 cm, body mass = 85.1 ± 17.8 kg performed four prescribed and four self-selected heavy metal songs. Oxygen consumption (VO2, minute ventilation (VE and respiratory exchange ratio (RER were measured using a metabolic cart.  Heart rate (HR was measured using a heart rate monitor. VO2max was determined using a graded cycle ergometer test. Results: The results indicated a metabolic cost of 6.3 ± 1.4 METs and heart rate of 145.1 ± 15.7 beats·min-1 (75.4 ± 8.3% of age-predicted HRmax. VO2 peak values reached approximately 90% of the drummer’s VO2max when performing at the fastest speeds. According to these results, heavy metal drumming may be considered vigorous intensity activity (≥ 6.0 METs. The relative VO2max of 40.2 ± 9.5 mL·kg·min-1 leads to an aerobic fitness classification of “average” for adult males. Conclusions: The metabolic demands required during heavy metal drumming meet the American College of Sports Medicine guidelines for the development of health related fitness. Keywords: Drum set, Exercise physiology, VO2, Music

  3. Remoção de metais pesados de efluentes aquosos pela zeólita natural escolecita - influência da temperatura e do pH na adsorção em sistemas monoelementares Heavy metals removal from wastewater by the natural zeolite scolecite - temperature and pH influence in single-metal solutions

    Ricardo Sarti Jimenez

    2004-10-01

    Full Text Available Cation exchange capabilities of a Brazilian natural zeolite, identified as scolecite, were evaluated for application in wastewater control. We investigated the process of sorption of chromium(III, nickel(II, cadmium(II and manganese(II in synthetic aqueous effluents, including adsorption isotherms of single-metal solutions. The natural zeolite showed the ability to take up the tested heavy metals in the order Cr(III > Cd(II > Ni(II > Mn(II, and this could be related to the valence and the hydration radius of the metal cations. The influence of temperature (25, 40 and 60 ºC and initial pH value (from 4 to 6 was also evaluated. It was found that the adsorption increased substantially when the temperature was raised to 60 ºC and that maximum adsorption capacity was observed at pH 6. These results demonstrate that scolecite can be used for removal of heavy metals from aqueous effluents, under optimized conditions.

  4. Removal Efficiency of Faecal Indicator Organisms, Nutrients and Heavy Metals from a Peri-Urban Wastewater Treatment Plant in Thohoyandou, Limpopo Province, South Africa

    Joshua N. Edokpayi

    2015-06-01

    Full Text Available Wastewater treatment facilities are known sources of fresh water pollution. This study was carried out from January to June 2014 to assess the reduction efficiency of some selected contaminants in the Thohoyandou wastewater treatment plant (WWTP. The pH and electrical conductivity of the effluent fell within the South African wastewater discharge guidelines. The WWTP showed the chemical oxygen demand reduction efficiency required by the Department of Water Affairs (DWA guidelines of 75 mg/L for the months of April and June, although it was below this standard in March and May. Free chlorine concentration varied between 0.26–0.96 mg/L and exceeded the DWA guideline value of 0.25 mg/L. The concentration of nitrate-nitrogen (NO3− N in the influent and effluent varied between 0.499–2.31 mg/L and 7.545–19.413 mg/L, respectively. The concentration of NO3− N in the effluent complied with DWA effluent discharge standard of 15 mg/L, except in April and May. Phosphate concentrations in the influent and effluent were in the ranges of 0.552–42.646 mg/L and 1.572–32.554 mg/L, respectively. The WWTP showed reduction efficiencies of E. coli and Enterococci during some sampling periods but the level found in the effluent exceeded the recommended guideline value of 1000 cfu/100 mL for faecal indicator organisms in wastewater effluents. Consistent removal efficiencies were observed for Al (32–74%, Fe (7–32% and Zn (24–94% in most of the sampling months. In conclusion, the Thohoyandou WWTP is inefficient in treating wastewater to the acceptable quality before discharge.

  5. Polymers contamination by heavy metal compounds

    Jovanić Saša

    2002-01-01

    Full Text Available The contamination of important synthetic (surface unmodified polymers by various heavy metal compounds (such as copper, manganese and lead in aqueous medium was investigated in this study. The influence of the pH of the aqueous medium, temperature and metal type on contamination was investigated during a 10 day period. It was found that increasing pH contributed to higher polymer contamination (at higher pH 100 times for copper and up to 400 times for lead, as well as contact with easily penetrable substances. Increasing temperature decreased contamination by the metal compound for PELD and PET which was not the case for PEHD and PR.

  6. A Review of Heavy Metals Immunoassay Detection

    Bing Lv

    2015-06-01

    Full Text Available Contamination of heavy metals in soil has been a significant problem, which resulted in food pollution and diseases through bioaccumulation. Traditional methods utilized to determined content of metal ions are time-cost, expensive and laboratorial. Since the introduction of antibody against In-EDTA, immunoassay has been developing for several decades. It filled in the blank of determination in situ with lower price and a short period. In this study, we mainly presented the research process of monoclonal antibody special binding to metal-ligand and the immunoassay utilized in detection of food and environment.

  7. The capture of heavy metals from incineration using a spray dryer integrated with a fabric filter using various additives.

    Liu, Z S; Wey, M Y; Lin, C L

    2001-07-01

    This study investigated the effects of feedstock additives [polyvinyl chloride (PVC) and NaCl] and spray dryer additives (SiO2, CaCl2, NaHCO3) on heavy metal and fly ash removal efficiencies, and on particle size distribution of heavy metals. A spray dryer with an integrated fabric filter was used as an air pollution control device (APCD). Removal efficiencies for fly ash and heavy metals were greater than 95 and 90%, respectively. When additives of PVC or NaCl were used, the concentration of heavy metals distributed in fly ash apparently varied when the particle diameter was 1 microm). PMID:15658217

  8. Heavy metals in MSW incineration fly ashes

    Ferreira, Celia; Ribeiro, Alexandra B.; Ottosen, Lisbeth M.

    2003-01-01

    characterized regarding its physical-chemical properties: pH, solubility, chemical composition, and leaching, amongst others. Results indicate a high alkalinity and the presence of large amounts of calcium, chlorides, sulfates, carbonates, sodium and potassium. Metal concentrations in fly ash are: 6,2 g/kg for......Incineration is a common solution for dealing with the increasing amount of municipal solid waste (MSW). During the process, the heavy metals initially present in the waste go through several transformations, ending up in combustion products, such as fly ash. This article deals with some issues...... related to the combustion of MSW and the formation of fly ash, especially in what concerns heavy metals. Treatment of the flue gas in air pollution control equipment plays an important role and the basic processes to accomplish this are explained. Fly ash from a semi-dry flue gas treatment system is...

  9. Heavy metal biosorption by bacterial cells

    Vecchio, A.; Finoli, C.; Di Simine, D.; Andreoni, V. [Department of Food Science and Microbiology, State University, Milan (Italy)

    1998-06-01

    Microbial biomass provides available ligand groups on which metal ions bind by different mechanisms. Biosorption of these elements from aqueous solutions represents a remediation technology suitable for the treatment of metal-contaminated effluents. The purpose of the present investigation was the assessment of the capability of Brevibacterium sp. cells to remove bivalent ions, when present alone or in pairs, from aqueous solutions, using immobilized polyacrylamide cells of the microorganism in a flow-through system. The biosorption capacity of Brevibacterium cells was studied for lead, cadmium and copper. The metal cell binding capacity followed the order Cu > Pb > Cd, based on estimated q{sub max}. These values, expressed as mmol metal/g dry weight cells, were 0.54 for Cu, 0.36 for Pb and 0.14 for Cd. Polyacrylamide-gel immobilized cells were effective in Pb, Cu and Cd removal. Lead removal was not affected by the presence of Cd and Cu; lead instead inhibited Cd and Cu removal. The desorption of the metal, by fluxing a chelating solution, restored the metal binding capacity of the cells, thus affording the multiple use of the same biomass in the remediation treatment. (orig.) (orig.) With 5 figs., 4 tabs., 23 refs.

  10. Minor heavy metal: A review on occupational and environmental intoxication

    Wiwanitkit Viroj

    2008-01-01

    Heavy metal is widely used in industries and presents as a problematic environmental pollution. Some heavy metals, especially lead and mercury, are well described for their occupational and environmental intoxication whereas the other minor heavy metals are less concerned. In this article, the author will present the details of occupational and environmental minor heavy metal intoxication. This review focuses mainly on aluminum, tin, copper, manganese, chromium, cadmium and nickel.

  11. Heavy Metal Concentrations in Maltese Potable Water

    Roberta Bugeja

    2015-05-01

    Full Text Available This study evaluates the levels of aluminum (Al, cadmium (Cd, chromium (Cr, copper (Cu, iron (Fe, lead (Pb, nickel (Ni and zinc (Zn in tap water samples of forty localities from around the Maltese Islands together with their corresponding service supply reservoirs. The heavy metal concentrations obtained indicated that concentrations of the elements were generally below the maximum allowed concentration established by the Maltese legislation. In terms of the Maltese and EU water quality regulations, 17.5% of the localities sampled yielded water that failed the acceptance criteria for a single metal in drinking water. Higher concentrations of some metals were observed in samples obtained at the end of the distribution network, when compared to the concentrations at the source. The observed changes in metal concentrations between the localities’ samples and the corresponding supply reservoirs were significant. The higher metal concentrations obtained in the samples from the localities can be attributed to leaching in the distribution network.

  12. Heavy metal tolerance in metal hyperaccumulator plant, Salvinia natans.

    Dhir, B; Srivastava, S

    2013-06-01

    Metal tolerance capacity of Salvinia natans, a metal hyperaccumulator, was evaluated. Plants were exposed to 10, 30 and 50 mg L⁻¹ of Zn, Cd, Co, Cr, Fe, Cu, Pb, and Ni. Plant biomass, photosynthetic efficiency, quantum yield, photochemical quenching, electron transport rate and elemental (%C, H and N) constitution remained unaffected in Salvinia exposed to 30 mg L⁻¹ of heavy metals, except for Cu and Zn exposed plants, where significant reductions were noted in some of the measured parameters. However, a significant decline was noted in most of the measured parameters in plants exposed to 50 mg L⁻¹ of metal concentration. Results suggest that Salvinia has fairly high levels of tolerance to all the metals tested, but the level of tolerance varied from metal to metal. PMID:23553503

  13. Arbuscular Mycorrhizal Fungi Can Benefit Heavy Metal Tolerance and Phytoremediation

    Forgy, David

    2012-01-01

    Sites contaminated by heavy metals, such as industrial waste sites, create unwelcoming environments for plant growth. Heavy metals can have a wide range of toxic effects such as replacing essential elements or disrupting enzyme function. While some heavy metals are essential to plant nutrition at low concentrations, high concentrations of any…

  14. ACCUMULATION OF HEAVY METALS IN BIOTA OF VYRLYTSA LAKE

    Bilyk, Tetiana; Tsurkan, Katerina; Koren, Lyudmila

    2011-01-01

    Abstract. The main task was to investigate the pollution by heavy metals of biota of Vyrlytsa Lake. Thecontents of movable forms of heavy metals in aquatic plants, fish and snails was determined by atomicabsorbtion method and were made the conclusions about general state of the water object.Keywords: heavy metals, accumulation, biota, pollution, atomic absorption spectroscopy.

  15. Effect of Heavy Metal Pollution on Cucumber POD Isoenzyme

    2003-01-01

    The Experiment was carried out to study heavy metal pollution effect on cucumber POD isozyme in our experiment.The results showed that:the activities of POD in cucumber seeds increased in low concentration treatment,and decreased in high concentration treatment after being treated with heavy metal.The critical band patterns of POD isoenzyme was changed by heavy metal pollution.

  16. Some Case Studies on Metal-Microbe Interactions to Remediate Heavy Metals- Contaminated Soils in Korea

    Chon, Hyo-Taek

    2015-04-01

    Conventional physicochemical technologies to remediate heavy metals-contaminated soil have many problems such as low efficiency, high cost and occurrence of byproducts. Recently bioremediation technology is getting more and more attention. Bioremediation is defined as the use of biological methods to remediate and/or restore the contaminated land. The objectives of bioremediation are to degrade hazardous organic contaminants and to convert hazardous inorganic contaminants to less toxic compounds of safe levels. The use of bioremediation in the treatment of heavy metals in soils is a relatively new concept. Bioremediation using microbes has been developed to remove toxic heavy metals from contaminated soils in laboratory scale to the contaminated field sites. Recently the application of cost-effective and environment-friendly bioremediation technology to the heavy metals-contaminated sites has been gradually realized in Korea. The merits of bioremediation include low cost, natural process, minimal exposure to the contaminants, and minimum amount of equipment. The limitations of bioremediation are length of remediation, long monitoring time, and, sometimes, toxicity of byproducts for especially organic contaminants. From now on, it is necessary to prove applicability of the technologies to contaminated sites and to establish highly effective, low-cost and easy bioremediation technology. Four categories of metal-microbe interactions are generally biosorption, bioreduction, biomineralization and bioleaching. In this paper, some case studies of the above metal-microbe interactions in author's lab which were published recently in domestic and international journals will be introduced and summarized.

  17. Biological removal of metal ions from aqueous process streams

    Aqueous waste streams from nuclear fuel processing operations may contain trace quantities of heavy metals such as uranium. Conventional chemical and physical treatment may be ineffective or very expensive when uranium concentrations in the range of 10 to 100 g/m3 must be reduced to 1 g/m3 or less. The ability of some microorganisms to adsorb or complex dissolved heavy metals offers an alternative treatment method. Uranium uptake by Saccharomyces cerevisiae NRRL Y-2574 and a strain of Pseudomonas aeruginosa was examined to identify factors which might affect a process for the removal of uranium from wastewater streams. At uranium concentrations in the range of 10 to 500 g/m3, where the binding capacity of the biomass was not exceeded, temperature, pH, and initial uranium concentration were found to influence the rate of uranium uptake, but not the soluble uranium concentration at equilibrium. 6 figs

  18. Irradiation of Liquid Fungi Isolated Media from Contaminated Sources with Heavy Metals Additive

    Occupational lead exposure is an important health issue in Egyptian workers, employees of paint factories, workers of copying centres, drivers, and tile making factories are in higher risk of lead toxicity. Wastewater, particularly from electroplating, paint, leather, metal and tanning industries, contain enormous amount of heavy metals. Microorganisms including fungi have been reported to exclude heavy metals from wastewater through bioaccumulation and bio sorption at low cost and in eco-friendly way. Low level lead exposure can significantly induce motor dis functions and cognitive impairment in children. Seventy six fungal isolates tolerant to heavy metals like Pb, Cd, Cr and Ni were isolated from sewage, sludge and industrial effluents containing heavy metals. Four fungi (Phanerochaete chrysosporium, Aspergillus awamori, Aspergillus flavus, Trichoderma viride) were included in this study. The majority of the fungal isolates were able to tolerate up to 400 ppm concentration of Pb, Cd, Cr and Ni. The most heavy metal tolerant fungi were studied for removal of heavy metals from liquid media at 50 ppm concentration. Results indicated removal of substantial amount of heavy metals by some of the fungi with respect to Pb, Cd, Cr and Ni with maximum uptake of 59.67, 16.25, 0.55 and 0.55 mg/g by fungi Pb3 (Aspergillus terreus), Trichoderma viride, Cr8 (Trichoderma longibrachiatum), and isolate Ni27 (A. niger), respectively. This indicated the potential of these fungi as bio sorbent for removal of heavy metals from wastewater and industrial effluents containing higher concentration of heavy metals. The F-ratio was 0.55 and gives non-significant as irradiated

  19. 红树白骨壤幼苗对水中重金属的吸附性能研究%Removal of Heavy Metal Ions with Avicennia marina Seedling

    王一兵; 柯珂; 陈奕君; 张荣灿; 雷富

    2015-01-01

    Objective]The absorption capabilities of Cu,Pb,Zn and Cd by Avicennia marina seedling were investigated to reduce the severe pollution in the offshore marine areas of Guangxi.[Methods]The Avicennia marina seedlings were obtained from the hypocotyls planted in sands with hoagland’s fluid,and then were cultured in hoagland’s fluid with dif-ferent concentrations of heavy metals.After 35 day’s cultivation,the contents of heavy met-als in Avicennia marina seedlings were determined by microwave digestion and atomic ab-sorption spectrometry.[Results]The increase of heavy metals concentration in the culture fluids led to the increase of heavy metals in the seedlings.The highest amount of heavy met-al is 980.78 μg/g of Cu,1623.03 μg/g of Pb,446.21 μg/g of Zn and 69.41 μg/g of Cd,re-spectively.The amounts of heavy metals in different part of seedlings is root > stem >leaf.This result meant that the heavy metal contents mainly were accumulated in root.The transport capability for different kind of heavy metals in the root and stem of seedlings were different.The transportation from easy to diffi-cult in seedling is Zn> Cu> Cd> Pb.[Conclu-sion]The Avicennia marina seedlings showed good absorption capabilities to 4 kinds of heavy metals in aqueous solution,especially to Pb and Cu.The Avicennia marina is a pro-spective plant for restoring the heavy metal pollution in estuary and offshore marine areas.%【目的】针对广西近岸海域重金属污染越来越严重的问题,研究红树白骨壤幼苗对水中重金属(Cu,Pb, Zn,Cd)的吸附去除性能。【方法】红树白骨壤幼苗采用砂培法由胚轴栽培而得,配制不同浓度混合重金属培养液对红树白骨壤幼苗胁迫培养35 d 后采用原子吸收光谱法测定其体内的重金属含量。【结果】随着培养液中重金属浓度的升高,红树白骨壤幼苗体内的重金属含量也逐渐增加,最高含量分别达到 Cu 980.78μg/g, Pb 1623.03

  20. Effects of remediation train sequence on decontamination of heavy metal-contaminated soil containing mercury.

    Hseu, Zeng-Yei; Huang, Yu-Tuan; Hsi, Hsing-Cheng

    2014-09-01

    When a contaminated site contains pollutants including both nonvolatile metals and Hg, one single remediation technology may not satisfactorily remove all contaminants. Therefore, in this study, chemical extraction and thermal treatment were combined as a remediation train to remove heavy metals, including Hg, from contaminated soil. A 0.2 M solution of ethylenediamine tetraacetic acid (EDTA) was shown to be the most effective reagent for extraction of considerable amounts of Cu, Pb, and Zn (> 50%). Hg removal was ineffective using 0.2 M EDTA, but thermogravimetric analysis suggested that heating to 550 degrees C with a heating rate of 5 degrees C/min for a duration of 1 hr appeared to be an effective approach for Hg removal. With the employment of thermal treatment, up to 99% of Hg could be removed. However executing thermal treatment prior to chemical extraction reduced the effectiveness of the subsequent EDTA extraction because nonvolatile heavy metals were immobilized in soil aggregates after the 550 degrees C treatment. The remediation train of chemical extraction followed by thermal treatment appears to remediate soils that have been contaminated by many nonvolatile heavy metals and Hg. Implications: A remediation train conjoining two or more techniques has been initialized to remove multiple metals. Better understandings of the impacts of treatment sequences, namely, which technique should be employed first on the soil properties and the decontamination efficiency, are in high demand. This study provides a strategy to remove multiple heavy metals including Hg from a contaminated soil. The interactions between thermal treatment and chemical extraction on repartitioning of heavy metals was revealed. The obtained results could offer an integrating strategy to remediate the soil contaminated with both heavy metals and volatile contaminants. PMID:25282998

  1. Removal of Selected Metals from Wastewater Using a Constructed Wetland.

    Šíma, Jan; Svoboda, Lubomír; Pomijová, Zuzana

    2016-05-01

    Removal of selected metals from municipal wastewater using a constructed wetland with a horizontal subsurface flow was studied. The objective of the work was to determine the efficiency of Cu, Zn, Ni, Co, Sr, Li, and Rb removal, and to describe the main removal mechanisms. The highest removal efficiencies were attained for zinc and copper (89.8 and 81.5%, respectively). It is apparently due to the precipitation of insoluble sulfides (ZnS, CuS) in the vegetation bed where the sulfate reduction takes place. Significantly lower removal efficiencies (43.9, 27.7, and 21.5%) were observed for Li, Sr, and Rb, respectively. Rather, low removal efficiencies were also attained for Ni and Co (39.8 and 20.9%). However, the concentrations of these metals in treated water were significantly lower compared to Cu and Zn (e.g., 2.8 ± 0.5 and 1.7 ± 0.3 μg/l for Ni at the inflow and outflow from the wetland compared to 27.6 ± 12.0 and 5.1 ± 4.7 μg/l obtained for Cu, respectively). The main perspective of the constructed wetland is the removal of toxic heavy metals forming insoluble compounds depositing in the wetland bed. Metal uptake occurs preferentially in wetland sediments and is closely associated with the chemism of sulfur and iron. PMID:27119624

  2. Perspectives of plant-associated microbes in heavy metal phytoremediation.

    Rajkumar, M; Sandhya, S; Prasad, M N V; Freitas, H

    2012-01-01

    "Phytoremediation" know-how to do-how is rapidly expanding and is being commercialized by harnessing the phyto-microbial diversity. This technology employs biodiversity to remove/contain pollutants from the air, soil and water. In recent years, there has been a considerable knowledge explosion in understanding plant-microbes-heavy metals interactions. Novel applications of plant-associated microbes have opened up promising areas of research in the field of phytoremediation technology. Various metabolites (e.g., 1-aminocyclopropane-1-carboxylic acid deaminase, indole-3-acetic acid, siderophores, organic acids, etc.) produced by plant-associated microbes (e.g., plant growth promoting bacteria, mycorrhizae) have been proposed to be involved in many biogeochemical processes operating in the rhizosphere. The salient functions include nutrient acquisition, cell elongation, metal detoxification and alleviation of biotic/abiotic stress in plants. Rhizosphere microbes accelerate metal mobility, or immobilization. Plants and associated microbes release inorganic and organic compounds possessing acidifying, chelating and/or reductive power. These functions are implicated to play an essential role in plant metal uptake. Overall the plant-associated beneficial microbes enhance the efficiency of phytoremediation process directly by altering the metal accumulation in plant tissues and indirectly by promoting the shoot and root biomass production. The present work aims to provide a comprehensive review of some of the promising processes mediated by plant-associated microbes and to illustrate how such processes influence heavy metal uptake through various biogeochemical processes including translocation, transformation, chelation, immobilization, solubilization, precipitation, volatilization and complexation of heavy metals ultimately facilitating phytoremediation. PMID:22580219

  3. Interaction of natural complexing agents with soil bound heavy metals -geochemical and environmental technical aspects

    The sanitation of heavy metal polluted soils requires the application of an adequate technology, which should be consistent in its ecological aims and methodology. Therefore a research programme has been developed at the 'Institute of Ecological Chemistry' of the 'GSF-Research Center', Neuherberg, which has its starting point in the study of influences of natural organic complexing agents on the chemical activity and dynamic of heavy metals in soils. The groundlaying idea is to elevate the concentration of complexing agents in the soil solution by additional application and possible stimulation of their microbial production to such an extent, that heavy metals will be enhanced solubilized, mobilized and removed together with the seepage water. Batch experiments in order to extract heavy metals from typical soil components (bentonite, peat) by amino acids demonstrate, that removal rates up to 95% can be obtained. (orig.)

  4. Polymers contamination by heavy metal compounds

    Jovanić Saša; Stoiljković Dragoslav M.; Popović Ivanka G.

    2002-01-01

    The contamination of important synthetic (surface unmodified) polymers by various heavy metal compounds (such as copper, manganese and lead) in aqueous medium was investigated in this study. The influence of the pH of the aqueous medium, temperature and metal type on contamination was investigated during a 10 day period. It was found that increasing pH contributed to higher polymer contamination (at higher pH 100 times for copper and up to 400 times for lead), as well as contact with easily p...

  5. Heavy metal burden of the Pinnau river

    The water phase and sediment of the Pinnau river were investigated for their heavy-metal pollution. Tests for the elements chromium, mercury, nickel, arsenic, lead, copper, cadmium, zinc and iron were carried through with sediment samples in 1984 and 1989 and with water samples in 1987 and 1989. Whereas no significant changes in the levels of these metals were found in the water phase during the two-year period of invetigation, slightly reduced levels of zinc, cadmium and mercury were established in the sediment in 1989 as compared to 1984. (orig.)

  6. Phytoremediation of Heavy Metal Pollution in Urban Sewage River Sediment by Lolium perenne

    2011-01-01

    [Objective] The aim was to restore heavy metal pollution of urban sewage river sediment by using Lolium perenne.[Method] Through cultivation test,the phytoremediation of heavy metal pollution in river sediment by L.perenne was analyzed from the aspects of removal effect,optimal removal time and the changes of sucrase activity,urease activity and microbe quantity.[Result] After planting L.perenne for three months,Ni content in sediment was basically stable,while the removal effect of Cr and Mn in sediment wa...

  7. Hydrate-based heavy metal separation from aqueous solution

    Song, Yongchen; Dong, Hongsheng; Yang, Lei; Yang, Mingjun; Li, Yanghui; Ling, Zheng; Zhao, Jiafei

    2016-01-01

    A novel hydrate-based method is proposed for separating heavy metal ions from aqueous solution. We report the first batch of experiments and removal characteristics in this paper, the effectiveness and feasibility of which are verified by Raman spectroscopy analysis and cross-experiment. 88.01–90.82% of removal efficiencies for Cr3+, Cu2+, Ni2+, and Zn2+ were obtained. Further study showed that higher R141b–effluent volume ratio contributed to higher enrichment factor and yield of dissociated water, while lower R141b–effluent volume ratio resulted in higher removal efficiency. This study provides insights into low-energy, intensive treatment of wastewater. PMID:26887357

  8. Phytoremediation of heavy metal from contaminated soil

    Soudek, Petr; Kališová, Ivana; Vaněk, Tomáš

    Praha : ÚOCHB AV ČR, 2003 - (Vaněk, T.; Schwitzguébel, J.), s. 65 ISBN 80-86241-19-X R&D Projects: GA MŠk OC 837.10; GA AV ČR IBS4055014; GA AV ČR IAA6055902 Institutional research plan: CEZ:AV0Z4055905 Keywords : heavy metals * phytoremediation * corn Subject RIV: DK - Soil Contamination ; De-contamination incl. Pesticides

  9. Evaluation of heavy metal complex phytotoxicity

    Vita Vasilyevna Datsenko; Nataliya Lvovna Khimenko

    2016-01-01

    The experimental data dealing with the effect of heavy metals contained in the technogenic contaminated soils on plant objects under controlled conditions was discussed. The aim of this work is to define the quantitative indicators of copper and zinc potential phytotoxicity, namely germination energy, simultaneous germination and duration of the test plants. It was found that the activity of the test plant growth is linked with copper and zinc complex action. Joint effect of copper and zinc i...

  10. Heavy metals occurrence in Italian food supplements

    Brizio P.; Benedetto A.; Squadrone S.; Tarasco R.; Gavinelli S.; Pellegrino M.; Abete M. C.

    2013-01-01

    In recent years a significant increase in food supplements consumption has been observed, maybe in the belief that they couldn’t be dangerous for consumers health, even if they don’t achieved medical effects. However, environmental pollution can cause heavy metals contamination that could exceed maximum levels established by European legislation. Aim of this work was to evaluate arsenic, cadmium, chromium, lead and mercury content in 12 food supplements seized in a Piedmont shop by the Italia...

  11. Geogenic heavy metal concentrations in German soils

    In the area of the German Federal Republic, 6,300 soil samples of 526 soil profiles were examined for the concentrations of lead, copper, zinc, cadmium, nickel, cobalt, mercury, antimony, arsenic and lithium. The soil profiles were selected so that the prevailing loose and solid rock floors of the German Federal Republic were represented. The analysis data of these samples formed the basis for the calculation of average geogenic heavy metal concentrations in the soils of the German Federal Republic. (orig.)

  12. Determination of heavy metals in fish scales

    Hana Nováková; Markéta Holá; Jozef Kaiser; Jiří Kalvoda; Viktor Kanický*

    2010-01-01

    The outcomes from measurements of amount of selected elements in the fish scales of common carp are presented. Concentrations in the scales were identified and differences between storage of heavy metals in exposed and covered part of scale were studied. The spatial distribution of elements on the fish scale´s surface layer was measured by Laser Ablation–Inductively Coupled Plasma–Mass Spectrometry (LA–ICP–MS). The average amount of elements in the dissolved scal...

  13. Phytoextraction of heavy metals by canola (Brassica napus) and radish (Raphanus sativus) grown on multicontaminated soil

    Marchiol, L.; Assolari, S.; Sacco, P.; Zerbi, G

    2004-11-01

    Phytoextraction can provide an effective in situ technique for removing heavy metals from polluted soils. The experiment reported in this paper was undertaken to study the basic potential of phytoextraction of Brassica napus (canola) and Raphanus sativus (radish) grown on a multi-metal contaminated soil in the framework of a pot-experiment. Chlorophyll contents and gas exchanges were measured during the experiment; the heavy metal phytoextraction efficiency of canola and radish were also determined and the phytoextraction coefficient for each metal calculated. Data indicated that both species are moderately tolerant to heavy metals and that radish is more so than canola. These species showed relatively low phytoremediation potential of multicontaminated soils. They could possibly be used with success in marginally polluted soils where their growth would not be impaired and the extraction of heavy metals could be maintained at satisfying levels.

  14. Phytoextraction of heavy metals by canola (Brassica napus) and radish (Raphanus sativus) grown on multicontaminated soil

    Phytoextraction can provide an effective in situ technique for removing heavy metals from polluted soils. The experiment reported in this paper was undertaken to study the basic potential of phytoextraction of Brassica napus (canola) and Raphanus sativus (radish) grown on a multi-metal contaminated soil in the framework of a pot-experiment. Chlorophyll contents and gas exchanges were measured during the experiment; the heavy metal phytoextraction efficiency of canola and radish were also determined and the phytoextraction coefficient for each metal calculated. Data indicated that both species are moderately tolerant to heavy metals and that radish is more so than canola. These species showed relatively low phytoremediation potential of multicontaminated soils. They could possibly be used with success in marginally polluted soils where their growth would not be impaired and the extraction of heavy metals could be maintained at satisfying levels

  15. Heavy Metals Acting as Endocrine Disrupters

    Bogdan Georgescu

    2011-10-01

    Full Text Available Last years researches focused on several natural and synthetic compounds that may interfere with the major functionsof the endocrine system and were termed endocrine disrupters. Endocrine disrupters are defined as chemicalsubstances with either agonist or antagonist endocrine effects in human and animals. These effects may be achievedby interferences with the biosynthesis or activity of several endogenous hormones. Recently, it was demonstratedthat heavy metals such as cadmium (Cd, arsen (As, mercury (Hg, nickel (Ni, lead (Pb and zinc (Zn may exhibitendocrine-disrupting activity in animal experiments. Emerging evidence of the intimate mechanisms of action ofthese heavy metals is accumulating. It was revealed, for example, that the Zn atom from the Zn fingers of theestrogen receptor can be replaced by several heavy metal molecules such as copper, cobalt, Ni and Cd. By replacingthe Zn atom with Ni or copper, binding of the estrogen receptor to the DNA hormone responsive elements in the cellnucleus is prevented. In both males and females, low-level exposure to Cd interferes with the biological effects ofsteroid hormones in reproductive organs. Arsen has the property to bind to the glucocorticoid receptor thusdisturbing glucocorticoids biological effects. With regard to Hg, this may induce alterations in male and femalefertility, may affect the function of the hypothalamo-pituitary-thyroid axis or the hypothalamo-pituitary-adrenal axis,and disrupt biosynthesis of steroid hormones.

  16. Heavy metal emissions for Danish road transport

    Winther, M.; Slentoe, E.

    2010-04-15

    This report presents new heavy metal emission factors for cars, vans, trucks, buses, mopeds and motorcycles for each of the emission sources fuel consumption, engine oil, tyre wear, brake wear and road abrasion. The emission components covered are Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Mercury (Hg), Nickel (Ni), Lead (Pb), Selenium (Se) and Zinc (Zn), all of them relevant for emission reporting to the UNECE CLRTAP (United Nations Economic Commission for Europe Convention on Long Range Transboundary Pollutants) convention. The report also presents a new Danish inventory for the year 2007. The following emissions in total TSP (in brackets) are calculated for the year 2007: As (8 kg), Cd (48 kg), Cr (197 kg), Cu (51 779 kg), Hg (28 kg), Ni (158 kg), Pb (6 989 kg), Se (33 kg) and Zn (28 556 kg). Per vehicle type cars are the most important source of emission for all heavy metal species, followed by vans, trucks, buses and 2-wheelers. By using the detailed emission factors and inventory calculation methods established in the present project, estimates of heavy metal emissions can be made for other years than 2007. (author)

  17. The Confluence of Heavy Metal Biooxidation and Heavy Metal Resistance: Implications for Bioleaching by Extreme Thermoacidophiles

    Garrett Wheaton; James Counts; Arpan Mukherjee; Jessica Kruh; Robert Kelly

    2015-01-01

    Extreme thermoacidophiles (Topt > 65 °C, pHopt < 3.5) inhabit unique environments fraught with challenges, including extremely high temperatures, low pH, as well as high levels of soluble metal species. In fact, certain members of this group thrive by metabolizing heavy metals, creating a dynamic equilibrium between biooxidation to meet bioenergetic needs and mechanisms for tolerating and resisting the toxic effects of solubilized metals. Extremely thermoacidophilic archaea dominate bio...

  18. Electrodialytic Separation of Phosphorus and Heavy Metals from Two Types of Sewage Sludge Ash

    Ottosen, Lisbeth M.; Jensen, Pernille Erland; Kirkelund, Gunvor Marie

    2014-01-01

    During sewage sludge incineration phosphorus (P) is retained in the ash in a form not directly available to plants. As P is a sparse resource, it is important to develop techniques for recovery of P from incinerated sewage sludge ashes (ISSA). Heavy metals are concentrated in ISSA and separation of...... P and heavy metals is required. The present work is an experimental screening of a new combination of acid extraction and electrodialysis–electrodialytic separation (EDS) for simultaneous P recovery and removal of heavy metals. Experiments were conducted with two different ashes; rich in Fe or Al...

  19. Surface binding of toxins and heavy metals by probiotics.

    Zoghi, Alaleh; Khosravi-Darani, Kianoush; Sohrabvandi, Sara

    2014-01-01

    Removal of toxic metals and toxins using microbial biomass has been introduced as an inexpensive, new promising method on top of conventional methods for decontamination of food, raw material and concentrated. In this article the potential application of lactic acid bacteria and yeasts as the most familiar probiotics to eliminate, inactivate or reduce bioavailability of contamination in foods and feed has been reviewed. After fast glance to beneficial health effects and preservative properties of lactic acid bacteria, the mechanisms which explain antibacterial and antifungal efficiency as well as their antifungal metabolites are mentioned. Then the article has been focused on potential application of single strain or combination of lactic acid bacteria for removal of heavy metals (copper, lead, cadmium, chromium, arsenic), cyanotoxins (microcystin-LR, -RR, -LF) and mycotoxins (aflatoxin B1, B2, B2a, M1, M2, G1, G2, patulin, ochratoxin A, deoxynivalenol, fumonisin B1 and B2, 3-acetyldeoxynivalenol, deoxynivalenol, fusarenon, nivalenol, diacetoxyscirpenol, HT-2 and T-2 toxin, zearalenone and its derivative, etc) from aqueous solutions in vitro. Wherever possible the mechanism of decontamination and the factors influencing yield of removal are discussed. Some factors which can facilitate metal removal capacity of lactic acid bacteria including the strains, surface charge, pH, temperature, presence of other cations are introduced. The cell wall structure of lactic acid bacteria and yeasts are also introduced for further explanation of mechanism of action in complex binding of probiotic to contaminants and strength of mycotoxin- bacterium interaction. PMID:24329992

  20. Recent advances in biosorption of heavy metals: support tools for biosorption equilibrium, kinetics and mechanism

    Hlihor, Raluca Maria; Bulgariu, Laura; Sobariu, Dana Luminita; Diaconu, Mariana; Tavares, T.; Gavrilescu, Maria

    2014-01-01

    Heavy metals are increasingly present in industrial wastes and effluents, which can generate serious concerns for environmental quality and human health. Consequently, there is a continuous expansion of researches for new approaches and developments to guarantee environmental cleaning-up. Although there are some physico-chemical established methods for the removal of heavy metals from various environmental compartments, biosorption gains further confidence as a reliable a...

  1. Optical Algal Biosensor using Alkaline Phosphatase for Determination of Heavy Metals

    Durrieu, Claude; Tran-Minh, Canh

    2002-01-01

    International audience A biosensor is constructed to detect heavy metals from inhibition of alkaline phosphatase (AP) present on the external membrane of Chlorella vulgaris microalgae. The microalgal cells are immobilized on removable membranes placed in front of the tip of an optical fiber bundle inside a homemade microcell. C. vulgaris was cultivated in the laboratory and its alkaline phosphatase activity is strongly inhibited in the presence of heavy metals. This property has been used ...

  2. Analysis of microbial community structures and functions in heavy metal-contaminated soils using molecular methods

    Gremion, Fabienne

    2003-01-01

    The contamination of agricultural land and groundwater by heavy metals is essentially linked to human activities. A major problem with heavy metals is that they cannot be biodegraded and therefore reside in the environment for long periods of time if they are not removed. Thus, depending of the kind and depth of contamination, different remediation techniques were developed. One of these methods, called "phytoextraction", uses the ability of so-called hyperaccumulating plants to extract high ...

  3. Analysis of microbial community structures and functions in heavy metal-contaminated soils using molecular methods

    Gremion, Fabienne; Harms, Hauke

    2005-01-01

    The contamination of agricultural land and groundwater by heavy metals is essentially linked to human activities. A major problem with heavy metals is that they cannot be biodegraded and therefore reside in the environment for long periods of time if they are not removed. Thus, depending of the kind and depth of contamination, different remediation techniques were developed. One of these methods, called "phytoextraction", uses the ability of so-called hyperaccumulating plants to extract high ...

  4. Electroremediation of heavy metals in sewage sludge

    C. Elicker

    2014-06-01

    Full Text Available This paper presents the application of electrokinetic remediation in the treatment of sludge in a sewage treatment station. The study consisted of, in a first step, the characterization of physicochemical parameters of sludge and, in a second step, the implementation of the electrokinetic remediation technique. The concentrations of Cu, Cr, Pb and Zn in sludge samples, before and after the experiment, were determined by atomic absorption spectroscopy. After 40 hours of experiment, considering an electrolyte flow-rate of 1.34 L.h-1 at a voltage of 20 V, the removal rate of all the metals accompanied was over 50%; the highest removal efficiency was for Pb, with 72.49%. The results show the feasibility of using the electrochemical technique of electrokinetic remediation for metal removal from a sludge sewage treatment station.

  5. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    Lima, A.T.

    2010-12-17

    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. © 2010 Elsevier Ltd.

  6. Biosorption and Metal Removal Through Living Cells

    Kotrba, P.; Macková, M.; Fišer, J.; Macek, Tomáš

    Dordrecht: Springer, 2011 - (Kotrba, P.; Macková, M.; Macek, T.), s. 197-233 ISBN 978-94-007-0442-8 R&D Projects: GA MŠk 1M06030 Grant ostatní: GA MŠk(CZ) 1M0520 Institutional research plan: CEZ:AV0Z40550506 Keywords : heavy metal * bioprecipitation * biotransformation * activated sludge * phytoremediation Subject RIV: EI - Biotechnology ; Bionics

  7. Fungal biotrap for retrieval of heavy metals from industrial wastewaters

    Biotraps are living cells or specific cell components capable of removing or stabilizing toxic substances form waste streams. The fungus Penicillium ochro-chloron was discovered growing in an electroplating wastewater stream in Japan. It is not only tolerant to very high concentrations of divalent metal ions, but it can effectively remove heavy metals (such as uranium cadmium, nickel, etc.) from almost any aqueous waste stream. This paper discussed P. ochro-chloron biotrap which was prepared by growing spores in a glucose-minimal salts medium supplemented with 0.5 percent Tween 80 for 5 days with constant gentle agitation. The while mycelia beads 4-6 mm dia. were treated in a Buchner funnel with 80% ethanol to kill the cells, 15 percent sodium carbonate/bicarbonate pH 9.5, and then resuspended in an aqueous slurry at pH 4.0. The mycelia beads were used as an adsorbent in a batch experiment to determine copper-to-mycelia binding. This system should be capable of heavy metal uptake and recovery from both electroplating wastewaters and contaminated aqueous environments. The use of this fungus biotrap will rival synthetic cation environments. The use of this fungus biotrap will rival synthetic cation exchange resins because of lower cost, lower weight per unit of exchange capacity and ease of application

  8. Sediment, water pollution indicators for heavy metals

    The complexity of an aquatic system requires consideration of its dynamics: spatial and temporal variations of physical, chemical and biological. Heavy metals have peculiar behavior in the aquatic system and may not be available in the waters, but on sediments.The sub-basin of the Sarandi stream is responsible for the contamination of Pampulha Lake. The Instituto Mineiro das Águas – IGAM - uses tool for monitoring the quality of surface water for developing strategies for conservation, restoration and rational use of water resources. So through the indices: IQA ( Indice de qualidade de águas) Index of water quality, and TC- toxic contamination, reduces conflicts, implements the disciplining of the environmental economy.This study determined the monitoring of sediment and water of Sarandi Stream, so in the samples collected during dry and rainy seasons (2007- 2008) were analyzed heavy metals (Cu, Cd, Cr, Co, Ni, Zn, Pb) and physical-chemical factors (conductivity, solids dissolved, temperature, turbidity). This allowed the determination of Hackanson factors of contamination and Muller Index geoaccumulation, indicating very high contamination in sediments regarding the elements Cr, Cu, and Cd, and high contamination for Pb, Zn, and Mn. The comparison with the indices of water quality- IQA (IGAM - 2006, 2007 and 2008), combined with exploratory data analysis and graphs of correlation between the variables indicated favorable conditions for metals contamination on water and sediment for these metals, besides allowing the identification of its source

  9. Magnetic filtration of heavy metals containing waters

    The high-intensity magnetic separation is applied above all in the beneficiation of fine-grained weakly magnetic ores, but also in the treatment of industrial, especially metallurgical and mining waters as well as of wastewaters from nuclear power stations. Similarly, it can be used in the field of geothermal energy supply and gases filtration. The magnetic separation or filtration respectively, directly enables the treatment of waters contaminated by solid ferromagnetic and paramagnetic particles. The magnetic filtration can remove heavy metals ions and even the oil substances by means of magnetic sorbents or special additives. The filtration of solid magnetic particles can be carried out in matrix-less and matrix separators. On the basis of mathematical description of particles dynamics and hydrodynamic conditions of suspension flow which resulted in the determination of geometrical parameters of separating zone the design of matrix-less magnetic separator was carried out. A strong, high-intensity magnetic field was created by means of a superconductive magnetic circuit. It was found out that for the achievement of optimal technological parameters during the magnetic separation of solid particles with grain size under 40 mm, the maximal solids concentration is to be 200 g/L. The design of matrix parameters and selection of inductive filling resides in theoretical considerations as well as in experimental works. Under laboratory condition the influence of following parameters on magnetic filtration process have been observed: the diameter of inductive ferromagnetic balls, the thickness of filtration layer, the intensity of magnetic field, the flow velocity of suspension, the density of suspension, the grain size of solids and the temperature of suspension. It was found that a spatial arrangement of inductive bodies in filtration layer influences not only the velocity of suspension flow but also a room size for catching of magnetic particles. The acting of magnetic

  10. Uptake of certain heavy metals from contaminated soil by mushroom--Galerina vittiformis.

    Damodaran, Dilna; Vidya Shetty, K; Raj Mohan, B

    2014-06-01

    Remediation of soil contaminated with heavy metals has received considerable attention in recent years. In this study, the heavy metal uptake potential of the mushroom, Galerina vittiformis, was studied in soil artificially contaminated with Cu (II), Cd (II), Cr (VI), Pb (II) and Zn (II) at concentrations of 50 and 100mg/kg. G. vittiformis was found to be effective in removing the metals from soil within 30 days. The bioaccumulation factor (BAF) for both mycelia and fruiting bodies with respect to these heavy metals at 50mg/kg concentrations were found to be greater than one, indicating hyper accumulating nature by the mushroom. The metal removal rates by G. vittiformis was analyzed using different kinetic rate constants and found to follow the second order kinetic rate equation except for Cd (II), which followed the first order rate kinetics. PMID:24655915

  11. Compost as a source of microbial isolates for the bioremediation of heavy metals: In vitro selection

    Vargas-Garcia, Maria del Carmen, E-mail: mcvargas@ual.es; Lopez, Maria Jose, E-mail: mllopez@ual.es; Suarez-Estrella, Francisca, E-mail: fsuarez@ual.es; Moreno, Joaquin, E-mail: jcasco@ual.es

    2012-08-01

    Heavy metal pollution has become a major environmental concern nowadays and the bioremediation of polluted habitats is an increasingly popular strategy due to both its efficiency and safety. A screening and selection protocol based on different composting processes was designed in order to isolate heavy metal-resistant microorganisms. A collection of 51 microorganisms was obtained and most of them showed the capability to tolerate heavy metals in multi-polluted aqueous systems (Cd(II), Cr(VI), Ni, Pb, Zn(II)), as well as to remove them. The highest detoxification ratios were observed for Pb. Some of the isolates detoxifying more than a 90% of this metal, while the other metals were removed in a range between 20% and 60%. The best isolates (Graphium putredinis, Fusarium solani, Fusarium sp. and Penicillium chrysogenum) were further assayed in order to determine the predominant removal mechanism and the potential use of their dead biomass as a biosorbent. Intracellular accumulation was the prevalent mechanism for most isolates and metals, with the exception of Ni. In this case, the proportion removed by extracellular adsorption was similar or even higher than that removed by intracellular accumulation. Thus, the efficiency of living cells was higher than that of dead biomass except in the case of Ni. - Highlights: Black-Right-Pointing-Pointer Composting is a good reservoir for the isolation of HM-resistant microorganisms. Black-Right-Pointing-Pointer Pb was the most removed heavy metal in multi-polluted aqueous systems. Black-Right-Pointing-Pointer Intracellular accumulation was the predominant mechanism for heavy metal removal. Black-Right-Pointing-Pointer Graphium putredinis, which detoxifies organic pollutants, was the most efficient isolate.

  12. Magnetotactic bacteria. Promising biosorbents for heavy metals

    Zhou, Wei; Zhang, Yanzong; Ding, Xiaohui; Liu, Yan; Shen, Fei; Zhang, Xiaohong; Deng, Shihuai; Xiao, Hong; Yang, Gang; Peng, Hong [Sichuan Agricultural Univ., Chengdu (China). Provincial Key Lab. of Agricultural Environmental Engineering

    2012-09-15

    Magnetotactic bacteria (MTB), which can orient and migrate along a magnetic line of force due to intracellular nanosized magnetosomes, have been a subject of research in the medical field, in dating environmental changes, and in environmental remediation. This paper reviews the recent development of MTB as biosorbents for heavy metals. Ultrastructures and taxis of MTB are investigated. Adsorptions in systems of unitary and binary ions are highlighted, as well as adsorption conditions (temperature, pH value, biomass concentration, and pretreatments). The separation and desorption of MTB in magnetic separators are also discussed. A green method to produce metal nanoparticles is provided, and an energy-efficient way to recover precious metals is put forward during biosorption. (orig.)

  13. Magnetotactic bacteria: promising biosorbents for heavy metals.

    Zhou, Wei; Zhang, Yanzong; Ding, Xiaohui; Liu, Yan; Shen, Fei; Zhang, Xiaohong; Deng, Shihuai; Xiao, Hong; Yang, Gang; Peng, Hong

    2012-09-01

    Magnetotactic bacteria (MTB), which can orient and migrate along a magnetic line of force due to intracellular nanosized magnetosomes, have been a subject of research in the medical field, in dating environmental changes, and in environmental remediation. This paper reviews the recent development of MTB as biosorbents for heavy metals. Ultrastructures and taxis of MTB are investigated. Adsorptions in systems of unitary and binary ions are highlighted, as well as adsorption conditions (temperature, pH value, biomass concentration, and pretreatments). The separation and desorption of MTB in magnetic separators are also discussed. A green method to produce metal nanoparticles is provided, and an energy-efficient way to recover precious metals is put forward during biosorption. PMID:22763846

  14. Broom fibre PRB for heavy metals groundwater remediation

    Molinari, A.; Troisi, S.; Fallico, C.; Paparella, A.; Straface, S.

    2009-04-01

    human being. One of the most interesting techniques applied in contaminated aquifer by heavy metals is the PRBs (Troisi et al., 2002; Calvin et al., 2006), in particular broom fibers PRB (Troisi et al., 2008). The first results highlight an optimum removal capacity for contaminants underlined from following removal percentage: 98.01% (Cd), 99.95% (Cu), 97.35% (Pb) and 99.53% (Zn). A fundamental parameter for PRB design is the decay coefficient who indicates the removal capacity (degradation, transformation, adsorption/absorption, mass transport, etc.). This parameter has been determined for four heavy metals: Cadmium (Cd), Copper (Cu), Lead (Pb) and Zinc (Zn) carrying out column tests. Besides, for real use of broom fibers PRB same tests have been performed, using flow cells, to estimate a relation between hydraulic conductivity of fiber and its density. References Chien C. C., H. I. Inyang and L.G. Everett (2006). Barrier Systems for Environmental Contaminant Containment and Treatment. Taylor and Francis Group eds. Troisi S., C. Fallico, S. Straface S. e L. Mazzuca. (2008). Biodreni per la bonifica di siti contaminati realizzati con fibre naturali liberiane ad elevato sviluppo superficiale. CS2008A00018. Università della Calabria. Troisi S, E. Migliari and S. Straface (2002). Soil and groundwater contamination by heavy metals in the industrial area of Crotone. Third International Conference Risk Analysis III. Sintra, Ed. by C.A. Brebbia. WIT Press.

  15. Biosorption of Lead and Copper by Heavy Metal Resistance Bacterium using Fourier Transform Infrared Spectrophotometer (FT IR

    This paper should be cited as: Mohseni M, Khosravi F, Mohadjerani M, Chaichi, MJ . [ Biosorption of Lead and Copper by Heavy Metal Resistance Bacterium using Fourier Transform Infrared Spectrophotometer (FT - IR ]. MLJ. 201 4 ; 8 ( 3 : [Article in Persian] Mohseni, M. (PhD

    2014-09-01

    Full Text Available Background and Objectives: Contamination of environment to lead and copper is rising due to human activities. One of the best methods to remove heavy metals from the environment is bacterial remediation. This study aimed to isolate bacteria and investigate the mechanism of lead and copper bioremediation. Material and Methods: Heavy metal resistant bacteria were isolated from contaminated wastewater samples. The isolates with high resistance to lead and copper were selected for further studies and bioremediation was assessed by atomic absorption spectrophotometer. To determine the functional groups to remove metals, FT-IR was employed. In addition, plasmid curing was studied to determine the location of the genes that are resistance to heavy metals. Results: Ten bacterial isolates that are resistance to heavy metals were isolated. Among these, MKH3 with the highest remediation activity removed %90 lead and %92 copper from the growth medium. The absorption mechanism of MKH3 indicated that the functional groups such as carboxyl, amide, carbonyl and hydroxyl were most effective for removal of heavy metals from the growth medium. The results revealed that heavy metal resistant genes may be located on plasmid DNA. Furthermore, molecular identification demonstrated that MKH3 was similar to Enterobacterhormaechei with 98% homology. Conclusion: Bacterium isolated from a contaminated site showed the ability to remove a high amount of lead and copper. Thus, MKH3 could be useful for the bioremediation of heavy metals, particularly lead and copper, from industrial wastewater and contaminated sites.

  16. Biochar Mechanisms of Heavy Metal Sorption and Potential Utility

    Ippolito, J.

    2015-12-01

    Mining-affected lands are a global issue; in the USA alone there are an estimated 500,000 abandoned mines encompassing hundreds of thousands of hectares. Many of these sites generate acidic mine drainage that causes release of heavy metals, and subsequently degradation in environmental quality. Because of its potential liming characteristics, biochar may play a pivotal role as a soil amendment in future mine land reclamation. However, to date, most studies have focused on the use of biochar to sorb metals from solution. Previous studies suggest that metals are complexed by biochar surface function groups (leading to ion exchange, complexation), coordination with Pi electrons (C=C) of carbon, and precipitation of inorganic mineral phases. Several recent studies have focused on the use of biochar for amending mine land soils, showing that biochar can indeed reduce heavy metal lability, yet the mechanism(s) behind labile metal reduction have yet to be established. In a proof-of-concept study, we added lodgepole pine, tamarisk, and switchgrass biochar (0, 5, 10, 15% by weight; 500 oC) to four different western US mine land soils affected by various heavy metals (Cd, Cu, Mn, Pb, Zn). Extraction with 0.01M CaCl2 showed that increasing biochar application rate significantly decreased 'bioaccessible' metals in almost all instances. A concomitant increase in solution pH was observed, suggesting that metals may be rendered bio-inaccessible through precipitation as carbonate or (hydr)oxide phases, or sorbed onto mineral surfaces. However, this was only supposition and required further research. Thus, following the 0.01M CaCl2 extraction, biochar-soil mixtures were air-dried and metals were further extracted using the four-step BCR sequential removal procedure. Results from selective extraction suggest that, as compared to the controls, most metals in the biochar-amended mine land soils were associated with exchange sites, carbonate, and oxide phases. Biochar may play a

  17. Development of a fluorescence heavy metal sensor

    This work as part of the European project S.O.F.I.E. (spectroscopy using optical fibres In the marine environment; MAS3-CT97-0157) describes the development of a fluorescence based heavy metal sensor. The target analytes Cadmium, Copper, Mercury and Lead were detected in seawater, either separately or as the total selection of the metals above. Two different approaches of heavy metal detection have been investigated, one by immobilising a dye into a sol-gel matrix, the second one using the ion-pair technique in PVC. The suitability of different dyes to form a metal dye complex in solution has been investigated and these have been immobilized into a sol-gel matrix. Although a signal of an immobilized metal-dye complex into sol-gel could be seen, it was impossible to achieve a recognition of analytes diffusing through the membrane, while significant leaching of the dye was observed. An extensive study on varying the sol-gel process was undertaken. The covalent binding of 5-amino-8-hydroxy quinoline to a sol-gel precursor showed sensitivity to a high concentration of cadmium. Due to the basic catalysed sol-gel used, the polymerization was too fast in order to achieve reproducible sol-gel films, which resulted in varying sensitivities. The second approach made use of the ion-pair technique. A metal ion selective ionophore, a pH indicator and a lipophilic anionic site were immobilized in plasticised poly(vinyl chloride)(PVC) matrix. The molar ratio of these compounds was found to be critical in terms of sensitivity and has been optimised in this work. To avoid leaching of any membrane component and thus to achieve a long lifetime of the sensor, highly hydrophobic, large compounds were used for the ion recognition layer. Employing this ion-pair technique resulted in a lead-sensor sensitive to the ppm concentration range with a response time of 45 minutes (while the reversible reaction took 15 hours). Finally, the achieved optode was tested together with those of the

  18. Detoxification of Heavy Metal Contaminated Soils

    Floarea Damian

    2007-01-01

    Full Text Available The concentration of the heavy metals in the soils from the strong affected zones because of the mining and metallurgical industry, Baia Mare and Zlatna (Romania, is significant due to the high values of the contents and association of the four metals Pb, Cu, Zn, Cd. The efficacy of the natural zeolites in heavy metals immobilization from the studied soils was evaluated in experiments in which the plant growth was observed. Heavy metals contaminated soils have been treated with a mixture of organic substance and zeolites (organo – zeolitic material. Zeolitic tuffs were roll-crushed and ground in small grains with dimensions between 0.05 and 2.0 mm. Clinoptilolite is the predominant zeolite and appears as compact masses of tabular and prismatic micron – sized crystals that are evident in SEM images. In the mixture, the polluted soil represents 83% and the organo – zeolitic material represents 17%. The soils used in the experiment are excessive contaminated with Pb (40375-1054ppm in association with Zn (1175-490ppm, Cd (24.2-13.2ppm and Cu (409.5-37.6ppm in Baia Mare zone and with Cu (7000-360ppm in association with Zn (3100-1900ppm, Cd (80-40ppm and Pb (2000-50ppm in Zlatna zone. The original soil and the treated soil have been planted with Lolium perenne. The growth of the plants has demonstrated that the soil treated with organo–zeolitic material allows the growth of vegetation much faster than the original soil. These results show that growth of the plants was possible because the organo–zeolitic material mixed with the soil provides the substances necessary for the plants to develop (ammonium, humus, potassium, calcium. At the same time, heavy metals that inhibit the plant development are blocked through the cationic exchange mechanism that makes them enter the zeolites structure and they no longer directly have access to the plant roots.

  19. The Confluence of Heavy Metal Biooxidation and Heavy Metal Resistance: Implications for Bioleaching by Extreme Thermoacidophiles

    Garrett Wheaton

    2015-07-01

    Full Text Available Extreme thermoacidophiles (Topt > 65 °C, pHopt < 3.5 inhabit unique environments fraught with challenges, including extremely high temperatures, low pH, as well as high levels of soluble metal species. In fact, certain members of this group thrive by metabolizing heavy metals, creating a dynamic equilibrium between biooxidation to meet bioenergetic needs and mechanisms for tolerating and resisting the toxic effects of solubilized metals. Extremely thermoacidophilic archaea dominate bioleaching operations at elevated temperatures and have been considered for processing certain mineral types (e.g., chalcopyrite, some of which are recalcitrant to their mesophilic counterparts. A key issue to consider, in addition to temperature and pH, is the extent to which solid phase heavy metals are solubilized and the concomitant impact of these mobilized metals on the microorganism’s growth physiology. Here, extreme thermoacidophiles are examined from the perspectives of biodiversity, heavy metal biooxidation, metal resistance mechanisms, microbe-solid interactions, and application of these archaea in biomining operations.

  20. Improvement Bio sorption of Heavy Metals from Industrial Wastewater Using Azolla

    This study aims to improve the removal process which is vital for some heavy metals and natural radionuclides from industrial wastewater by bio sorption using living organisms with rapid growth as a trial to increase the efficient use of those organisms in the removal process is vital for the toxic elements. Bio sorption of heavy metal (Copper, Manganese, Iron, Zinc, Lead and Strontium) from industrial waste water (contaminated) with six different time periods for Azolla growth. The results indicate that Azolla plant able to on the absorption of ions of heavy elements and Sr and was up to the maximum absorption of most of the elements at a concentration of 50% of polluted water + 50% fresh water so we recommend using the plant Azolla as bio sorbent in the disposal and collection of heavy metals and radionuclides from industrial waste water and deal with it safely to humans and the environment. The results obtained confirm the ability of the fern to grow and absorb ion of heavy metal when mixed with industrial waste water and other sources of polluted water and act as bio filter. The optimum conditions for maximum removal of heavy metals were also determined. Study was conducted on recycling municipal wastewaters for cultivation of Azollamicrophylla biomass, which is used for inoculation into paddy fields as N bio fertilizer and has other applications as green manure,animal feed and bio filter.

  1. Determination of the levels of heavy metals in cocoa products

    Fermented and dried cocoa beans from all the major cocoa-producing regions in Ghana were analyzed for levels of the following heavy metals: arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, nickel and zinc. The shells of the beans which usually do not form a part of the edible portion of the beans were removed and analyzed separately from the cocoa nibs (de-shelled beans) for all the elements above. To determine the distribution of metals during processing of the beans soxhlet extractions of fat from pulverised cocoa nibs was performed and cocoa powders obtained analyzed for their levels of heavy metals. Three commercial brands of 'natural' cocoa powders on the local market were also analyzed to determine the levels of these metals. The analyses were performed using an inductively coupled plasma - optical emission spectrophotometer (ICP-OES) following a microwave-assisted digestion process. The levels of toxic metals lead, cadmium and arsenic were found to be low (≤ 0.020 μg/g, ≤ 0.087 μg/g, < 0.001 μg/g, respectively) and well within the acceptable limits set by the WHO (0.100 μg/g, 0.100 μg/g, and 0.010 μg/g respectively). However, the levels of zinc copper, iron and manganese were however quite high. With a high fat content of the cocoa beans (approximately 50%) and greater portioning of metals into the non-fat portions of the beans, metals levels were considerably higher (almost double) in processed cocoa than in the cocoa itself. (au)

  2. Heavy Metal Contents of Lake Sapanca

    YALÇIN, Nevin; SEVİNÇ, Vahdettin

    2001-01-01

    The heavy metal pollution of Lake Sapanca located in the Marmara region (Turkey), was investigated over time. The lake is the drinking water source of the city of Adapazarı and its environs. The D-80 (TEM) motorway passes about 5 km along the lake's zero point in the Sapanca district. The motorway's wastewater drainages have been connected to the lake without having been subjected to any wastewater treatment. The motorway was opened to service in October 1990. Analyses w...

  3. Evaluation of heavy metal complex phytotoxicity

    Vita Vasilyevna Datsenko

    2016-07-01

    Full Text Available The experimental data dealing with the effect of heavy metals contained in the technogenic contaminated soils on plant objects under controlled conditions was discussed. The aim of this work is to define the quantitative indicators of copper and zinc potential phytotoxicity, namely germination energy, simultaneous germination and duration of the test plants. It was found that the activity of the test plant growth is linked with copper and zinc complex action. Joint effect of copper and zinc is manifested both in inhibition of lettuce growth and determined, above all, by the nature contamination, soil properties and biological specificity of the test plants.

  4. Geneticaly modified flax for heavy metal phytoremediation

    Najmanová, J.; Kotrba, P.; Macek, Tomáš; Macková, Martina

    Praha : VŠCHT, 2007 - (Macková, M.; Macek, T.; Demnerová, K.; Pazlar, V.; Nováková, M.), s. 167-168 ISBN 978-80-7080-026-3. [Symposium on Biosorption and Bioremediation /4./. Praha (CZ), 26.08.2007-30.08.2007] R&D Projects: GA MŠk 1M06030 Grant ostatní: GA MŠk(CZ) OC 117 Institutional research plan: CEZ:AV0Z40550506 Keywords : phytoremediation * heavy metal s * glutathione * flax * transformation Subject RIV: EI - Biotechnology ; Bionics

  5. Determination of heavy metals in fish scales

    Hana Nováková

    2010-12-01

    Full Text Available The outcomes from measurements of amount of selected elements in the fish scales of common carp are presented. Concentrations in the scales were identified and differences between storage of heavy metals in exposed and covered part of scale were studied. The spatial distribution of elements on the fish scale´s surface layer was measured by Laser Ablation–Inductively Coupled Plasma–Mass Spectrometry (LA–ICP–MS. The average amount of elements in the dissolved scales was quantified by ICP–MS. The fine structure of fish scales was visualized by phase–contrast Synchrotron radiation (SR microradiography.

  6. Applicability of Moringa oleifera Lam. pie as an adsorbent for removal of heavy metals from waters Aplicabilidade da torta de Moringa oleifera Lam. como adsorvente para remoção de metais pesados de águas

    Affonso C. Gonçalves Junior

    2013-01-01

    Full Text Available This study evaluated the efficacy of moringa seeds (Moringa oleifera Lam. as an adsorbent material for removing toxic heavy metals such as cadmium, lead, and chromium from contaminated solutions. The effect of the adsorbent mass was investigated at two pH conditions (5.0 and 7.0. The optimized conditions were 0.300 g of adsorbent at pH 5.0, used for the isotherms construction, and linearized according to Langmuir and Freundlich models. Results showed that cadmium adsorption was similar in both the models used. For lead, the Freundlich model had the best adjustment and chromium was better adjusted by the Langmuir model. It was concluded that the adsorbent was effective in the remediation of solutions containing cadmium, lead and chromium, thus, its use as sustainable alternative material is feasible, since it has low cost, does not need a previous treatment and it is a byproduct.Este estudo objetivou avaliar a eficácia do uso da torta de moringa (Moringa oleifera Lam. como material adsorvente dos metais pesados tóxicos cádmio (Cd, chumbo (Pb e cromo (Cr de soluções contaminadas. Nos testes cinéticos foram variadas as massas do adsorvente em duas condições de pH (5,0 e 7,0. As condições otimizadas foram pH 5,0 e massa de 0.300 g de adsorvente, utilizados para a construção das isotermas e linearizadas conforme os modelos de Langmuir e Freundlich. Realizou-se a determinação dos metais por espectrometria de absorção atômica. Os resultados mostraram que houve semelhança em ambos os modelos utilizados para a adsorção do Cd. Para o Pb, o modelo de Freundlich apresentou o melhor ajuste e, para o Cr, houve melhor ajuste pelo modelo de Langmuir. Conclui-se, com base nos resultados obtidos, que o adsorvente foi eficaz na remediação de soluções contendo Cd, Pb e Cr e, assim, é viável a utilização desse adsorvente como material alternativo sustentável, pois apresenta baixo custo, não necessita de tratamento prévio e se trata de

  7. Growth and heavy metals accumulation potential of microalgae grown in sewage wastewater and petrochemical effluents.

    Ajayan, K V; Selvaraju, M; Thirugnanamoorthy, K

    2011-08-15

    Microalgae exhibit a number of heavy metal uptake process by different metabolism. In this study, the ability of microalgae for removal of heavy metal from wastewater was studied. Growth and biochemical contents of microalgae were determined by spectrophotometer. Heavy metal analysis of wastewater effluents were performed by atomic absorption spectrophotometer before and after treatment at laboratory scale. The growth of Scenedesmus bijuga and Oscillatoria quadripunctulata in sewage wastewater was higher than those grown in synthetic medium. Whereas, the growth of S. bijuga and O. quadripunctulata in sterilized petrochemical effluents was slightly lower than that grown in the standard synthetic medium. The chlorophyll, carotenoid and protein content of S. bijuga and O. quadripunctulata grown in sterilized sewage wastewater were higher than those grown in the standard medium. Similarly S. bijuga and O. quadripunctulata grown in sterilized petrochemical effluents showed lower contents of pigments and protein than those grown in sewage and synthetic medium. Heavy metals copper, cobalt, lead and zinc were removed by 37-50, 20.3-33.3, 34.6-100 and 32.1-100%, respectively from sewage wastewater and petrochemical effluent using Ocillatoria culture. The metal absorption by S. bijuga were (Cu, Co, Pb, Zn) 60-50, 29.6-66, 15.4-25 and 42.9-50%, respectively from sewage and petrochemical effluents. Both species showed high level of heavy metal removal efficiency and metal sorption efficiency of both microalgae depended on the type of biosorbent, the physiological status of the cells, availability of heavy metal, concentration of heavy metal and chemical composition of wastewater. PMID:22545355

  8. Bioleaching remediation of heavy metal-contaminated soils using Burkholderia sp. Z-90.

    Yang, Zhihui; Zhang, Zhi; Chai, Liyuan; Wang, Yong; Liu, Yi; Xiao, Ruiyang

    2016-01-15

    Bioleaching is an environment-friendly and economical technology to remove heavy metals from contaminated soils. In this study, a biosurfactant-producing strain with capacity of alkaline production was isolated from cafeteria sewer sludge and its capability for removing Zn, Pb, Mn, Cd, Cu, and As was investigated. Phylogenetic analysis using 16S rDNA gene sequences confirmed that the strain belonged to Burkholderia sp. and named as Z-90. The biosurfactant was glycolipid confirmed by thin layer chromatography and Fourier-transform infrared spectroscopy. Z-90 broth was then used for bioleaching remediation of heavy metal-contaminated soils. The removal efficiency was 44.0% for Zn, 32.5% for Pb, 52.2% for Mn, 37.7% for Cd, 24.1% for Cu and 31.6% for As, respectively. Mn, Zn and Cd were more easily removed from soil than Cu, Pb and As, which was attributed to the presence of high acid-soluble fraction of Mn, Zn and Cd and high residual fraction of Cu, Pb and As. The heavy metal removal in soils was contributed to the adhesion of heavy metal-contaminated soil minerals with strain Z-90 and the formation of a metal complex with biosurfactant. PMID:26348147

  9. Heavy metal decontamination of sludges and soils. Pt. 2

    This research project deals with decontamination technology for contaminated soil and sediments. A pilot plant for the decontamination of soil contaminated with heavy metals has been erected and is operated. The process is arranged in two steps: - heavy metal contaminated solid is decontaminted with acidic extraction. - the heavy metals are separated in a recyclable formation from the process solution you gain in the first process step. Heavy metal contaminated soil, heavy metal contaminated sediments (habour sediments) as well as residue from a soil regeneration plant have been successfully decontaminated in the pilot plan. An adaption of the process is necessary for various materials. High rates of mobilisation of heavy metals (e.g. lead, cadmium, chromium, copper, nickel, zinc) were obtained, especially with soil which contains less organic matter. (orig.). 54 figs., 30 tabs., 45 refs

  10. Atmospheric heavy metal deposition in Europe estimated by moss analysis

    Ruehling, Aa. [Swedish Environmental Research Inst., Lund (Sweden). Dept. of Ecology

    1995-12-31

    Atmospheric heavy metal deposition in Europe including 21 countries was monitored in 1990-1992 by the moss technique. This technique is based on the fact that the concentrations of heavy metals in moss are closely correlated to atmospheric deposition. This was the first attempt to map heavy metal deposition in this large area. The objectives of the project were to characterise qualitatively and quantitatively the regional atmospheric deposition pattern of heavy metals in background areas in Europe, to indicate the location of important heavy metal pollution sources and to allow retrospective comparisons with similar studies. The present survey is a follow-up of a joint Danish and Swedish project in 1980 and an extended survey in 1985 within the framework of the Nordic Council of Ministers. In Sweden, heavy-metal deposition was first mapped on a nation-wide scale in 1968-1971 and 1975. (author)

  11. Heavy metals occurrence in Italian food supplements

    Brizio P.

    2013-04-01

    Full Text Available In recent years a significant increase in food supplements consumption has been observed, maybe in the belief that they couldn’t be dangerous for consumers health, even if they don’t achieved medical effects. However, environmental pollution can cause heavy metals contamination that could exceed maximum levels established by European legislation. Aim of this work was to evaluate arsenic, cadmium, chromium, lead and mercury content in 12 food supplements seized in a Piedmont shop by the Italian authority against food adulteration. All metals were analysed after mineralization and dilution steps by ICP-MS, with the exception of mercury, detected by the direct analyser TDA-AAS. Only one sample exceed the European maximum limits for lead (3,00 mg/kg but warning levels of chromium (over 3,00 mg/Kg has been detected in three of them.

  12. Heavy metal adsorption by sulphide mineral surfaces

    Jean, Gilles E.; Bancroft, G. Michael

    1986-07-01

    The adsorption of aqueous Hg 2+, Pb 2+, Zn 2+ and Cd 2+ complexes on a variety of sulphide minerals has been studied as a function of the solution pH and also as a function of the nature of the ligands in solution. Sulphide minerals are excellent scavengers for these heavy metals. The adsorption is strongly pH dependent, i.e. there is a critical pH at which the adsorption increases dramatically. The pH dependence is related to the hydrolysis of the metal ions. Indirect evidence suggests that the hydrolyzed species are adsorbed directly on the sulphide groups, probably as a monolayer. The results also suggest the presence of MCI n2- n species physisorbed on the adsorbed monolayer. A positive identification of the adsorbed species was not possible using ESCA/XPS.

  13. A Better Method for Evaluating Heavy Metal Water Pollution

    Hering, Janet

    2002-01-01

    High concentrations of heavy metals, and even trace amounts of some, can be harmful to both plants and animals. The toxicity of heavy metal contamination, however, is highly dependent on the chemical form of the metal in question. Metals that are bound in particles or to organic (carbon-containing) compounds are less toxic than dissolved free ions, less toxic meaning that the metals are less readily available for uptake by marine organisms.

  14. Behavior and Distribution of Heavy Metals Including Rare Earth Elements, Thorium, and Uranium in Sludge from Industry Water Treatment Plant and Recovery Method of Metals by Biosurfactants Application

    Lidi Gao

    2012-01-01

    Full Text Available In order to investigate the behavior, distribution, and characteristics of heavy metals including rare earth elements (REEs, thorium (Th, and uranium (U in sludge, the total and fractional concentrations of these elements in sludge collected from an industry water treatment plant were determined and compared with those in natural soil. In addition, the removal/recovery process of heavy metals (Pb, Cr, and Ni from the polluted sludge was studied with biosurfactant (saponin and sophorolipid elution by batch and column experiments to evaluate the efficiency of biosurfactant for the removal of heavy metals. Consequently, the following matters have been largely clarified. (1 Heavy metallic elements in sludge have generally larger concentrations and exist as more unstable fraction than those in natural soil. (2 Nonionic saponin including carboxyl group is more efficient than sophorolipid for the removal of heavy metals in polluted sludge. Saponin has selectivity for the mobilization of heavy metals and mainly reacts with heavy metals in F3 (the fraction bound to carbonates and F5 (the fraction bound to Fe-Mn oxides. (3 The recovery efficiency of heavy metals (Pb, Ni, and Cr reached about 90–100% using a precipitation method with alkaline solution.

  15. Behavior and Distribution of Heavy Metals Including Rare Earth Elements, Thorium, and Uranium in Sludge from Industry Water Treatment Plant and Recovery Method of Metals by Biosurfactants Application

    Gao, Lidi; Kano, Naoki; Sato, Yuichi; Li, Chong; Zhang, Shuang; Imaizumi, Hiroshi

    2012-01-01

    In order to investigate the behavior, distribution, and characteristics of heavy metals including rare earth elements (REEs), thorium (Th), and uranium (U) in sludge, the total and fractional concentrations of these elements in sludge collected from an industry water treatment plant were determined and compared with those in natural soil. In addition, the removal/recovery process of heavy metals (Pb, Cr, and Ni) from the polluted sludge was studied with biosurfactant (saponin and sophorolipid) elution by batch and column experiments to evaluate the efficiency of biosurfactant for the removal of heavy metals. Consequently, the following matters have been largely clarified. (1) Heavy metallic elements in sludge have generally larger concentrations and exist as more unstable fraction than those in natural soil. (2) Nonionic saponin including carboxyl group is more efficient than sophorolipid for the removal of heavy metals in polluted sludge. Saponin has selectivity for the mobilization of heavy metals and mainly reacts with heavy metals in F3 (the fraction bound to carbonates) and F5 (the fraction bound to Fe-Mn oxides). (3) The recovery efficiency of heavy metals (Pb, Ni, and Cr) reached about 90–100% using a precipitation method with alkaline solution. PMID:22693485

  16. Stabilization and separation of heavy metals in incineration fly ash during the hydrothermal treatment process.

    Hu, Yuyan; Zhang, Pengfei; Li, Jianping; Chen, Dezhen

    2015-12-15

    In the paper, hydrothermal treatment (HT) of MSWI fly ashes was performed to stabilize and separate heavy metals. Influences of pre-treatment, types of ferric and/or ferrous additives, and subsequent heavy metal stabilization procedure by adding phosphate were investigated. The chemical stability of hydrothermal products was examined by solid waste extraction procedure with acetic acid buffer solution. Mineralogical investigation of selected hydrothermal product was carried out by XRD. FEGE SEM- -EDX was used to study the morphology and surface compositions of the ash particles. Experimental results revealed that HT process facilitated heavy metal exposure to leaching solution. FEGE SEM-EDX images revealed that fly ash particles were re-organized during hydrothermal process and that the minerals with special shapes and containing high levels of heavy metals were formed. A mild acid washing treatment with final pH around 6.20 could remove soluble heavy metals. Therefore, it may be a proper pre- or post-treatment method for fly ash particles for the purpose of reducing heavy metal contents. For the purpose of stabilizing heavy metals, the addition of ferric/ferrous salts in the HT process or phosphate stabilization after HT is recommended. The HT process may be applied to realize the environmentally sound management of MSWI fly ash or to recover and utilize MSWI fly ash. PMID:26100935

  17. Leaching heavy metals from the surface soil of reclaimed tidal flat by alternating seawater inundation and air drying.

    Guo, Shi-Hong; Liu, Zhen-Ling; Li, Qu-Sheng; Yang, Ping; Wang, Li-Li; He, Bao-Yan; Xu, Zhi-Min; Ye, Jin-Shao; Zeng, Eddy Y

    2016-08-01

    Leaching experiments were conducted in a greenhouse to simulate seawater leaching combined with alternating seawater inundation and air drying. We investigated the heavy metal release of soils caused by changes associated with seawater inundation/air drying cycles in the reclaimed soils. After the treatment, the contents of all heavy metals (Cd, Pb, Cr, and Cu), except Zn, in surface soil significantly decreased (P carbonate, reducible, and oxidizable fractions also significantly decreased (P carbon decreased the amount of heavy metals in the oxidizable fraction. Furthermore, complexation of chloride ions and competition of cations during seawater inundation and/or leaching decreased the levels of heavy metals in the exchangeable fraction. By contrast, air drying significantly enhanced the concentration of heavy metals in the exchangeable fraction. Therefore, the removal of heavy metals in the exchangeable fraction can be enhanced during subsequent leaching with seawater. PMID:27236846

  18. Leaching of heavy metals from steelmaking slags

    Gomes, J. F. P

    2006-12-01

    Full Text Available Leaching tests with EAF and Ladle slags were performed, using a flow through test and the standard batch test DIN 38414-S4. The previous method was used to simulate the leaching behaviour of steel slags under landfill. The chemical analysis of the leachates during this period shows, in general, for both types of slag, an increase of heavy metal releases with ageing. Standard test method DIN 38414-S4 was used to evaluate leachability of heavy metals by water in unprocessed slags. After more than one year of trials, slag samples submitted to these trials presented very low total leaching levels. The most extracted elements are calcium and magnesium. Nevertheless, in flow-through test, calcium and magnesium leached from solid slags are below 0.5% and all other metals below 0.1%. Leachates obtained with DIN 38414-S4 present, as expected, higher leaching values; however, these are inferior to 5 % (Ca and 1% (other elements.

    Este articulo contiene los resultados obtenidos en ensayos de lixiviación de escorias de acero (horno electrico y cuchara ejecutados siguiendo la metodologia de flujo dinámico así como el ensayo normalizado DIN 38414-S4. El primer ensayo intenta simular el comportamiento de lixiviación de las escorias en vertedero. Para las escorias ensayadas se han complementado los ensayos con el análisis químico de los lixiviados y se ha verificado un aumento de la liberación de metales pesados. El ensayo DIN 38414-S4 se ha utilizado para evaluar la lixiviación por agua de metales pesados, en muestras de escorias originales. Despues de un año de ensayos, se han observado niveles muy bajos de lixiviación. Los elementos mas lixiviados han sido calcio y magnesio. No obstante, en los ensayos de flujo dinámico, el calcio y el magnesio lixiviados de las escorias sólidas era menor de 0,5% y el resto de los otros metales era inferior a 0,1%. Los lixiviados obtenidos con el ensayo DIN 38414-S4 presentan, como era de esperar, valores

  19. Biosorption of heavy metal ions from aqueous solution by red macroalgae.

    Ibrahim, Wael M

    2011-09-15

    Biosorption is an effective process for the removal and recovery of heavy metal ions from aqueous solutions. The biomass of marine algae has been reported to have high biosorption capacities for a number of heavy metal ions. In this study, four species of red seaweeds Corallina mediterranea, Galaxaura oblongata, Jania rubens and Pterocladia capillacea were examined to remove Co(II), Cd(II), Cr(III) and Pb(II) ions from aqueous solution. The experimental parameters that affect the biosorption process such as pH, contact time and biomass dosage were studied. The maximum biosorption capacity of metal ions was 105.2mg/g at biomass dosage 10 g/L, pH 5 and contact time 60 min. The biosorption efficiency of algal biomass for the removal of heavy metal ions from industrial wastewater was evaluated for two successive cycles. Galaxaura oblongata biomass was relatively more efficient to remove metal ions with mean biosorption efficiency of 84%. This study demonstrated that these seaweeds constitute a promising, efficient, cheap and biodegradable sorbent biomaterial for lowering the heavy metal pollution in the environment. PMID:21798665

  20. Organic leaching and metal removal with Sargassum filipendula

    Márcia Teresinha Veit

    2014-02-01

    Full Text Available The biosorption process with algae is usually carried out with a concomitant alginate leaching process. Alginate is identified as the main functional group, responsible for generating the most active sites. Biomass chemical and thermal pretreatment is an alternative process for reducing organic leaching. Experiments with different pH rates were performed to analyze the leaching process of pretreated (contact time: 24, 48 and 72 hours and non-pretreated biomass of Sargassum filipendula. The concentrations of calcium, magnesium, sodium and potassium ions, as well as total organic carbon, were determined to evaluate the biomass sorption capacity. Capacities of native and pretreated biomass to remove the heavy metal ions Cr and/or Ni from solutions of different concentrations were compared. The ion competition effect on removal capacity was studied. The biosorbent had a higher affinity with chromium ion.

  1. 采用废弃农林生物质吸附和回收重金属研究进展%Adsorption removal and recovery of heavy metal pollutants by agricultural and forestry wastes

    李晓森; 卢滇楠; 刘铮

    2012-01-01

    Agricultural and forestry wastes have the adsorption capacity of heavy metal ions,which can be used as biological adsorption applied in the industrial wastewater treatment and recovery of valuable heavy metals.This review focused on the recent advancement in the adsorption mechanism,adsorbent innovation and the downstream processing of the metal concentrates.The problems in research and development of agricultural and forestry wastes based adsorbent were also discussed.This review revealed the microscopic process of adsorption,clarified the role of the structure and composition related to the adsorption in the cell wall and determined the mechanism of adsorption of the heavy metal.The article pointed out that the development of new efficient biological adsorbents which perform high selectivity and adsorption capacity is the key step for application.After the adsorption of heavy metals,further processing is necessary for industrialization.%废弃农林生物质对重金属离子具有吸附能力,可望用于回收工业污水中的重金属。本文对废弃农林生物质对重金属的吸附机理、吸附剂研发、吸附产物资源化利用等方面的研究进展进行了介绍,讨论了废弃农林生物质对重金属吸附技术研究中存在的问题和解决途径。揭示吸附的微观过程、阐明与吸附作用有关的生物质细胞壁结构和成分、确定重金属吸附机理以及开发新的高效的生物质吸附剂等是寻找具有高选择性和高吸附能力的高效生物质吸附剂的关键;对生物质吸附重金属后的进一步处理是工业化的必由途径。

  2. HEAVY METALS CONTENT IN SHEEP PRODUCTS FROM MIDLE SPIŠ

    Slávik Marek; Tóth Tomáš; Kopernická Miriama; Árvay Július; Harangozo Ľuboš

    2015-01-01

    In this work, we evaluated the risk of contamination of animal products by heavy metals. Samples of animal raw materials were obtained in 2013 in the municipalities of Porac and Matejovce nad Hornádom. Samples of muscle and internal organs were collected from domestic sheep (Ovis aries) reared in the village of Rudnianska burdened area where mercury along with other heavy metals contamination is above the limit value of agricultural soil. Measuring the concentration of heavy metals in the sam...

  3. Impact of heavy metals on the female reproductive system

    Piotr Rzymski; Katarzyna Tomczyk; Pawel Rzymski; Barbara Poniedziałek; Tomasz Opala; Maciej Wilczak

    2015-01-01

    Introduction. It has been recognized that environmental pollution can affect the quality of health of the human population. Heavy metals are among the group of highly emitted contaminants and their adverse effect of living organisms has been widely studied in recent decades. Lifestyle and quality of the ambient environment are among these factors which can mainly contribute to the heavy metals exposure in humans. Objective. A review of literature linking heavy metals and the female repr...

  4. BIOSORPTION AND RECOVERY OF HEAVY METALS FROM AQUEOUS SOLUTIONS BY EICHHORNIA CRASSIPES (WATER HYACINTH) ASH

    Tariq Mahmood; Salman Akbar Malik; Syed Tajammul Hussain

    2010-01-01

    Heavy metal’s release without treatment poses a significant threat to the environment. Heavy metals are non-biodegradable and persistent. In the present study the ash of water hyacinth (Eichhornia crassipes), was used to remove six metals from aqueous solutions through biosorption. Results of batch and column experiments showed excellent adsorption capacity. Removal of lead, chromium, zinc, cadmium, copper, and nickel was 29.83, 1.263, 1.575, 3.323, 2.984 and 1.978 µgg-1, respectively. The bi...

  5. Optimización del Proceso de Remoción de Metales Pesados de Agua Residual de la Industria Galvánica por Precipitación Química Optimization of the Removal Processs of Heavy Metals from Raw Water of Galvanic Industry by Chemical Precipitation

    Eduardo Soto

    2006-01-01

    Full Text Available Se han estudiado las condiciones óptimas requeridas para remover metales pesados del agua residual de una industria galvánica, que contiene cromo (435 mg/L, zinc (720 mg/L, hierro (168 mg/L y níquel (24 mg/L. Se usó agua preparada en el laboratorio (agua sintética y agua de la industria misma (agua cruda. El tratamiento se hizo mediante precipitación química, usando sosa para ajustar el pH y cloruro férrico como aditivo coagulante en un equipo de prueba de jarras. Las condiciones óptimas encontradas usando el agua sintética fueron: 7 minutos para el tiempo de floculación, 18 rpm para la velocidad de agitación y 11.8 mL para la dosis de coagulante. Para el agua cruda fueron: 9.5 minutos para el tiempo de floculación, 30 rpm para la velocidad de agitación y 5.2 mL para la dosis de coagulante. Las condiciones de tratamiento fueron diferentes para el agua residual cruda, ya que el agua residual cruda contiene otros contaminantes, los cuales sobrecargan la superficie coloidal, esto afecta el proceso de floculaciónThe aim of this research was to obtain the optimum conditions to remove heavy metals from wastewaters of the galvanic industry, which contain chromium (435 mg/L, zinc (720 mg/L, iron (168 mg/L and nickel (24 mg/L. The treatment was made by chemical precipitation using caustic soda to set pH and ferric chloride like coagulant aid in jar test. The responses to optimize are: flocculation time, stirring speed and coagulant dose. The optimum conditions to remove heavy metals from synthetic wastewater was, flocculation time: 7 minutes, stirring speed: 18 rpm, coagulant dose: 11.8 mL and flocculation time: 9.5 minutes,stirring speed: 30 rpm, coagulant dose: 5.2 mL for raw wastewater. The treatment conditions were different for the raw wastewater because the raw wastewater contains other pollutants which over charge the colloidal surface and affects the flocculation processes

  6. Effects of heavy metal adsorption on silicene

    Kaloni, Thaneshwor P.

    2014-06-02

    Based on first-principles calculations, we study the effects of heavy metal atoms (Au, Hg, Tl, and Pb) adsorbed on silicene. We find that the hollow site is energetically favorable in each case. We particulary address the question how the adsorption modifies the band structure in the vicinity of the Fermi energy. Our results demonstrate that the heavy metal adatoms result in substantial energy gaps and band splittings in the silicene sheet as long as the binding is strong, which, however, is not always the case. (© 2014 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) Carbon nanotube flexible sponge was manufactured as high performance electromagnetic shielding material. Chemical vapour deposition (CVD) synthesized sponges with extreme light weight show an electromagnetic shielding above 20 dB and a specific electromagnetic shielding as high as 1100 dB cm3g-1 in the whole 1-18 GHz range. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Heavy metal screening in compounds feeds

    Tomas Toth

    2015-05-01

    Full Text Available Heavy metals are generally classified as basic groups of pollutants that are now a days found in different environmental compartments. This is quite a large group of contaminants, which have different characteristics, effects on the environment and sources of origin. For environment pose the greatest risks, especially heavy metals produced by anthropogenic activities that adversely affect the health and vitality of organisms and natural environmental conditions. Livestock nutrition is among the main factors which affect not only the deficiency of livestock production and quality of food of animal origin, but they are also a factor affecting the safety and wholesomeness and the animal health. Compound feeds is characterized as a mixture of two or more feed grain. Containing organic, inorganic nutrients and specifically active compound feed meet the nutritional requirements of a given kind and age category of animals. They are used mainly in the diet of pigs, poultry, but also the nutrition of cattle, sheep, horses and other animal categories. The basic ingredients are cereals in proportion of 60-70 %. The aim of this thesis was to analyze the content of hazardous elements (copper, zinc, iron, manganese, cobalt, nickel, chromium, lead, cadmium, mercury in 15 samples of compound feeds and then evaluating their content in comparison with maximum limits laid down by Regulation of the Government of the Slovak Republic and Regulation Commission (EC.

  8. Comparison of Eleven Heavy Metals in Moringa Oleifera Lam. Products

    Limmatvapirat, C.; Limmatvapirat, S.; Charoenteeraboon, J.; Wessapan, C.; Kumsum, A.; Jenwithayaamornwech, S.; P Luangthuwapranit

    2015-01-01

    Eleven heavy metals in various products of Moringa oleifera were analyzed to determine eleven heavy metals (Al, As, Cd, Cr, Cu, Fe, Pb, Mn, Hg, Ni, and Zn) using Inductively Coupled Plasma-Mass Spectrometry. The products of M. oleifera were purchased in Nakhon Pathom, Thailand. All products were digested with nitric acid solution before determining the concentrations of heavy metals. The recoveries of all heavy metals were found to be in the range of 99.89-103.05%. Several criteria such as li...

  9. THE HEAVY METALS CONNTENT IN VEGETABLES FROM MIDDLE SPIŠ AREA

    Marek Slávik,Tomáš Tóth; Július Árvay; Miriama Kopernická; Luboš Harangozo; Radovan Stanovič; Pavol Trebichalský; Petra Kavalcová

    2014-01-01

    In the middle area of Spiš, it is significantly burden by heavy metals what is documented by radical content of Hg in soil from Rudňany 58.583645 mg.kg -1. On the content of heavy metals in vegetables grown in this soil it has the same effect. 61.5% samples exceeded the limit value of heavy metals. The most dangerous vegetables were Lactuca sativa L. The limit value was exceed in all determine heavy metals - Hg, Cd, Pb and Cu in this vegetables. In the case of Hg, the limit value exceed 93.86...

  10. Research on Distribution Pattern of Heavy Metals in Yanzhou Coalfield

    ZHOU Guang-zhu; YANG Feng-jie; CHENG Jian-guang; Wang Cui-zhen

    2005-01-01

    Heavy metal pollution brings extensive concerns since 1940s. In order to assess the heavy metal pollution on the farmland of Yanzhou coalfield, 216 soil samples and 54 combined samples were collected. Lead, cadmium, chromium, copper, zinc, and nickel contained in both topsoil and deep soil were analyzed using atomic absorbent spectrometry analyzer (AAS). Fuzzy clustering method was used in data processing. And fuzzy synthetic assessment was applied to assess the soil contamination by heavy metals. The result shows that Yanzhou coalfield has been polluted by the heavy metals to some extent.

  11. Extraction kinetics of heavy metal-containing sludge.

    Lee, I-Hsien; Wang, Yi-Jing; Chern, Jia-Ming

    2005-08-31

    In order to remove and recover copper, zinc, cadmium, and chromium from the wastewater treatment sludge generated by an electroplating process, the heavy metal extraction kinetics was studied in a batch reactor using two different extraction agents (nitric and citric acid) at constant agitation speed (150 rpm) and solid to liquid ratio (10 g/L), but varying acid concentrations (0.02-0.10 N), temperatures (25-85 degrees C in nitric acid solution, 25-95 degrees C in citric acid solution), and sludge particle sizes. The shrinking-core model and empirical kinetic model were adopted to analyze the experimental data. Although both models could fit the experimental kinetic data well, the obtained parameters of the shrinking-core model did not show reasonable trends varying with the experimental variables while the empirical model parameters showed significant trends. The experimental and modeling results showed that the metal extraction rates increased with acid concentration, temperature, but decreased with increasing particle size. Nitric acid was found to be more effective than citric acid to extract the heavy metals from the sludge. The extraction activation energies obtained in this study suggested that both a physical diffusion process and a chemical reaction process might play important roles in the overall extraction process. PMID:15993295

  12. Neutron removal in peripheral relativistic heavy ion collisions

    We investigate the relativistic Coulomb fragmentation of 197Au by heavy ions, leading to one-, two- and three-neutron removal. To resolve the ambiguity connected with the choice of a specific minimum impact parameter in a semiclassical calculation, a microscopic approach is developed based on nucleon-nucleon collisions ('soft-spheres' model). This approach is compared with experimental data for 197Au at 1 GeV/nucleon and with a calculation using the 'sharp-cutoff' approximation. We find that the harmonic-oscillator model predicting a Poisson distribution of the excitation probabilities of multiphonon states gives a good agreement with one-neutron removal cross sections but is unable to reach an equally good agreement with three-neutron removal cross sections. (orig.)

  13. HEAVY METALS IN MIDDLE NITRA RIVERSIDE

    Silvia Čéryová

    2012-02-01

    Full Text Available Present state of environment is widely affected by various impacts of man which significantly eliminate negative affecting of its influence on the environment. In the past this fact was not so implemented and thus there was uncontrolled escape of contaminants of organic, but also inorganic origin into various components of environment. The most sensitive component is water ecosystem and its close plates (base sediments, banks sediments and biosphere near the flows. River Nitra ranks among the most affected water ecosystems in SR that was in 1965 the recipient of sludge, that was by accident in Zemianske Kostoľany uncontrolled spilled into the river with aftermath of long-term contamination of all sub-components in ecosystem, mainly by heavy metals (Hg, As, Pb, etc.. Soil contamination by Cd and Hg was analytically confirmed. The contents of these risk elements in soil extract of aqua regia 1.85 - 3.7 fold (Cd and 4.57- 36.3 fold (Hg exceeded the limit values (0.4 mg.kg-1 and 0.15 mg.kg-1 respectively given by the legislative. Other metals exceeding limit values were lead (1.064 - 1.072 fold, zinc (1.096 - 1.192 fold and chromium (1.172 – 1.644 fold. From assessed soil content of heavy metals only bioavailable forms of Pb determined in soil extract by NH4NO3 2.0 - 3.3 fold exceeded the limit value 0.1 mg.kg-1.

  14. Keywords in heavy metal lyrics : A Data-Driven Corpus Study into the Lyrics of Five Heavy Metal Subgenres

    Taina, Jesse

    2014-01-01

    Heavy metal -musiikkia on akateemisessa maailmassa tutkittu vain vÀhÀn. Tutkimuksen kohteena on yleensÀ ollut heavy metal genrenÀ tai kulttuurisena ilmiönÀ. Ne harvat tutkimukset, jotka ovat keskittyneet heavy metal -kappaleiden sanoituksiin, ovat useimmiten ottaneet lÀhtökohdakseen kvalitatiivisen metodin. TÀmÀ tutkimus hyödyntÀÀ kvantitatiivisia menetelmiÀ. Tutkimuksen lÀhtökohtana on tutkia heavy metal -kappaleiden sanoituksia tilastollisesti korpuslingvistisiÀ metode...

  15. Heavy liquid metal technologies development in Kalla

    The thermo-physical properties of Heavy Liquid Metals (Pb and Pb-Bi Eutectic) such as the low melting and high boiling temperatures, the chemical inertness in direct contact with typical reactor coolants, makes HLMs to relevant candidates as core coolant of critical and sub-critical nuclear systems. In addition the high neutron yield obtained by proton irradiation renders this material attractive for the development of neutron spallation sources. The practical use of HLM as core coolant and spallation material needs to be validated by experimental and computational activities. In this frame the KALLA (Karlsruhe Lead Laboratory) program, which consists of several stagnant and loop experiments, has been defined. Currently KALLA represents one of the most relevant infrastructures, which is in operation in Europe. The capabilities of KALLA make it possible to evaluate thermal-hydraulics parameters in complex geometries, to develop techniques for local and global quantities measurement, to assess the materials compatibility in different conditions and to evaluate basic chemical-physical data as for instance the wetting capability of the liquid metal. The aim of this article is to discuss the most significant development conducted at KALLA to support the activities of Accelerator Driven Transmutation Systems and to overview the experiences gained with the operation of liquid metal facilities. The loop experiments are now operated continuously since several years and a broad experience has been gained for the individual components typically appearing in reactors like pump systems (both electromagnetic and mechanical), oxygen monitoring and control systems, etc. (authors)

  16. Heavy metal contamination in bats in Britain

    Walker, L.A. [NERC Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS (United Kingdom); Simpson, V.R. [Wildlife Veterinary Investigation Centre, Jollys Bottom Farm, Chacewater, Truro, Cornwall TR4 8PB (United Kingdom); Rockett, L. [NERC Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS (United Kingdom); Wienburg, C.L. [NERC Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS (United Kingdom); Shore, R.F. [NERC Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS (United Kingdom)]. E-mail: rfs@ceh.ac.uk

    2007-07-15

    Toxic metals are bioaccumulated by insectivorous mammals but few studies (none from Britain) have quantified residues in bats. We measured renal mercury (Hg), lead (Pb) and cadmium (Cd) concentrations in bats from south-west England to determine how they varied with species, sex, age, and over time, and if they were likely to cause adverse effects. Residues were generally highest in whiskered bats (Myotis mystacinus). Compared with other species, pipistrelle (Pipistrellus spp) and Natterer's bats (Myotis nattereri) had significantly lower kidney Hg and Pb concentrations, respectively. Renal Hg increased over time in pipistrelles but the contributory sources are unknown. Kidney Pb did not decrease over time despite concurrent declines in atmospheric Pb. Overall, median renal metal concentrations were similar to those in bats from mainland Europe and 6- to 10-fold below those associated with clinical effect, although 5% of pipistrelles had kidney Pb residues diagnostic of acute lead poisoning. - Heavy metal contamination has been quantified in bats from Britain for the first time and indicates increased accumulation of Hg and no reduction in Pb.

  17. Heavy metal contamination in bats in Britain

    Toxic metals are bioaccumulated by insectivorous mammals but few studies (none from Britain) have quantified residues in bats. We measured renal mercury (Hg), lead (Pb) and cadmium (Cd) concentrations in bats from south-west England to determine how they varied with species, sex, age, and over time, and if they were likely to cause adverse effects. Residues were generally highest in whiskered bats (Myotis mystacinus). Compared with other species, pipistrelle (Pipistrellus spp) and Natterer's bats (Myotis nattereri) had significantly lower kidney Hg and Pb concentrations, respectively. Renal Hg increased over time in pipistrelles but the contributory sources are unknown. Kidney Pb did not decrease over time despite concurrent declines in atmospheric Pb. Overall, median renal metal concentrations were similar to those in bats from mainland Europe and 6- to 10-fold below those associated with clinical effect, although 5% of pipistrelles had kidney Pb residues diagnostic of acute lead poisoning. - Heavy metal contamination has been quantified in bats from Britain for the first time and indicates increased accumulation of Hg and no reduction in Pb

  18. PROCESS FOR SEPARATION OF HEAVY METALS

    Duffield, R.B.

    1958-04-29

    A method is described for separating plutonium from aqueous acidic solutions of neutron-irradiated uranium and the impurities associated therewith. The separation is effected by adding, to the solution containing hexavalent uranium and plutonium, acetate ions and the ions of an alkali metal and those of a divalent metal and thus forming a complex plutonium acetate salt which is carried by the corresponding complex of uranium, such as sodium magnesium uranyl acetate. The plutonium may be separated from the precipitated salt by taking the same back into solution, reducing the plutonium to a lower valent state on reprecipitating the sodium magnesium uranyl salt, removing the latter, and then carrying the plutonium from ihe solution by means of lanthanum fluoride.

  19. New biosorbent in removing some metals from industrial wastewater in El Mex Bay, Egypt

    Abdallah, Maha Ahmed Mohamed; Mahmoud, Mohamed E.; Osman, Maher M.; Ahmed, Somaia B.

    2015-12-01

    Biosorption is an extensive technology applied for the removal of heavy metal ions and other pollutants from aqueous solutions. In the present study, the biosorption of cadmium, lead, chromium and mercury ions from polluted surface seawater in El-Max Bay was determined using hybrid active carbon sorbents. These sorbents were treated chemically by acid, base and redox reaction followed by surface loading of baker's yeast biomass for increasing their biosorption capacity and the highest metal uptake values. The surface function and morphology of the hybrid immobilized sorbents were studied by Fourier Transform Infrared analysis and scanning electron microscope imaging. Metal removal values proved that the vital role of baker's yeast as a significant high removable due to functional groups at baker's yeast cell wall surface that have the ability to forming various coordination complexes with metal ions. A noticeable increase in the removal of all studied metals was observed and reached to 100 %.

  20. Electrodialytic treatment for metal removal from sewage sludge ash from fluidized bed combustion

    Pazos, Marta; Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.

    2010-01-01

    FBSC was studied. A detailed characterization of the sewage sludge ash was done initially, determining that, with the exception of Cd, the other heavy metals (Cr, Cu, Pb, Ni and Zn) were under the limiting levels of Danish legislation for the use of sewage sludge as fertilizer. After 14 days of...... concentration in FBSC ash prior to use as fertilizer....... treat sewage sludge. By its use, the high amount of sludge is reduced to a small quantity of ash and thermal destruction of toxic organic constituents is obtained. Conversely, heavy metals are retained in the ash. In this work the possibility for electrodialytic metal removal for sewage sludge ash from...