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Sample records for water treatment adsorbents

  1. Treatment of Refinery Waste Water Using Environmental Friendly Adsorbent

    Science.gov (United States)

    Devi, M. Geetha; Al-Moshrafi, Samira Mohammed Khamis; Al Hudaifi, Alaa; Al Aisari, Buthaina Hamood

    2017-09-01

    This research evaluates the effectiveness of activated carbon prepared from walnut shell in the removal of pollutants from refinery waste water by adsorption technique. A series of batch experiments were carried out by varying the effluent solution pH, stirring time, stirring speed and adsorbent dosage in the reduction of pollutants from refinery effluent. Characterization of the adsorbent was performed using Scanning Electron Microscopy (SEM), Brunauer Emmett and Teller (BET) isotherm and Fourier Transform Infrared (FTIR) Spectroscopy. The best quality activated carbon was obtained with a particle size of 0.75 µm, activation temperature of 800 °C and activation time 24 h. The maximum BET surface area obtained was 165.2653 m2/g. The experimental results demonstrates that the highest percentage reduction in COD was 79%, using 0.6 g walnut shell powder at an optimum stirring speed of 100 rpm, at pH 6 and 120 min of contact time. The outcome of the result shows that walnut shell carbon is a potentially useful adsorbent for the removal of pollutants from refinery waste water.

  2. Adsorbed Water Illustration

    Science.gov (United States)

    2008-01-01

    The Thermal and Electrical Conductivity Probe on NASA's Phoenix Mars Lander detected small and variable amounts of water in the Martian soil. In this schematic illustration, water molecules are represented in red and white; soil minerals are represented in green and blue. The water, neither liquid, vapor, nor solid, adheres in very thin films of molecules to the surfaces of soil minerals. The left half illustrates an interpretation of less water being adsorbed onto the soil-particle surface during a period when the tilt, or obliquity, of Mars' rotation axis is small, as it is in the present. The right half illustrates a thicker film of water during a time when the obliquity is greater, as it is during cycles on time scales of hundreds of thousands of years. As the humidity of the atmosphere increases, more water accumulates on mineral surfaces. Thicker films behave increasingly like liquid water. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  3. Preparation and characterization of adsorbents for treatment of water associated with oil production

    KAUST Repository

    Sueyoshi, Mark

    2012-09-01

    Two sets of adsorbents were prepared from locally available raw materials, characterized and tested. The first set consists of crushed natural attapulgite and crushed attapulgite mixed with petroleum tank-bottom sludge and carbonized at 650 °C. Another set was prepared using trunk of date palm tree (Phoenix dactylifera) activated at 700 and 800°C. Both sets were characterized using BET surface area and pore distributions, FTIR, XRD, SEM and TEM. Natural attapulgite and attapulgite/sludge composite exhibited different characteristics and adsorptive capacities for oil removal from oily water. Adsorptive capacities were calculated from the breakthrough curves of a column test. An oily water solution of about 500 mg-oil/L was passed through both the attapulgite and attapulgite/sludge columns until the column effluent concentration exceeded a reference limit of 10 mg-oil/L. Uptake was calculated at this limit at 155 and 405 mg-oil/g-adsorbent, respectively. This was lower than the performance of a commercial activated carbon sample (uptake calculated at 730 mg-oil/g-adsorbent). Relatively, the date palm, carbonaceous-based adsorbent samples showed less significant differences in both bulk and surface properties. Uptake significantly improved to 1330-1425 mg-oil/g-adsorbent. Attempt was made to associate this performance with the difference in the surface areas between the two sets. However, other factors are found to be important as the second set has a range of surface area less than that of the commercial sample. As evidenced by FTIR, XRD and TEM, the activated carbonaceous materials developed porous structures which form defective graphitic sheet ensembles that serve as additional adsorption sites in the sample. © 2012 Elsevier B.V.

  4. Hybrid materials: Magnetite-Polyethylenimine-Montmorillonite, as magnetic adsorbents for Cr(VI) water treatment.

    Science.gov (United States)

    Larraza, Iñigo; López-Gónzalez, Mar; Corrales, Teresa; Marcelo, Gema

    2012-11-01

    Hybrid materials formed by the combination of a sodium rich Montmorillonite (MMT), with magnetite nanoparticles (40 nm, Fe(3)O(4) NPs) coated with Polyethylenimine polymer (PEI 800 g/mol or PEI 25000 g/mol) were prepared. The intercalation of the magnetite nanoparticles coated with PEI among MMT platelets was achieved by cationic exchange. The resulting materials presented a high degree of exfoliation of the MMT sheets and a good dispersion of Fe(3)O(4) NPs on both the surface and among the layers of MMT. The presence of amine groups in the PEI structure not only aids the exfoliation of the MMT layers, but also gives to the hybrid material the necessary functionality to interact with heavy metals. These hybrid materials were used as magnetic sorbent for the removal of hexavalent chromium from water. The effect that pH, Cr(VI) concentration, and adsorbent material composition have on the Cr(VI) removal efficiency was studied. A complete characterization of the materials was performed. The hybrid materials showed a slight dependence of the removal efficiency with the pH in a wide range (1-9). A maximum amount of adsorption capacity of 8.8 mg/g was determined by the Langmuir isotherm. Results show that these hybrid materials can be considered as potential magnetic adsorbent for the Cr(VI) removal from water in a wide range of pH. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Selection of an adsorbent for lead removal from drinking water by a point-of-use treatment device.

    Science.gov (United States)

    Sublet, Renaud; Simonnot, Marie-Odile; Boireau, Alain; Sardin, Michel

    2003-12-01

    The removal of lead from drinking water was investigated to develop a point-of-use water filter that could meet the regulation imposed by the new European Directive 98-83 lowering lead concentration in drinking water below 10 microgL(-1). The objective of this research was to assess the potential of different adsorbents (zeolites, resins, activated carbon, manganese oxides, cellulose powder) to remove lead from tap water with a very short contact time. To begin, the repartition of the lead species in a tap water and a mineral water was computed with the computer model CHESS. It showed that in bicarbonated waters lead is mainly under lead carbonate form, either in the aqueous or in the mineral phase. Batch experiments were then conducted to measure the equilibrium adsorption isotherms of the adsorbents. Then, for five of them, dynamic experiments in micro-columns were carried out to assess the outlet lead concentration level. Three adsorbents gave rise to a leakage concentration lower than 10 microgL(-1) and were then selected for prototypes experiments: chabasite, an activated carbon coated with a synthetic zeolite and a natural manganese oxide. The proposed method clearly showed that the measurement of equilibrium isotherms is not sufficient to predict the effectiveness of an adsorbent, and must be coupled with dynamic experiments.

  6. Polymer composite adsorbents using particles of molecularly imprinted polymers or aluminium oxide nanoparticles for treatment of arsenic contaminated waters.

    Science.gov (United States)

    Önnby, L; Pakade, V; Mattiasson, B; Kirsebom, H

    2012-09-01

    Removal of As(V) by adsorption from water solutions was studied using three different synthetic adsorbents. The adsorbents, (a) aluminium nanoparticles (Alu-NPs, polymers (polymer backbones of pure polyacrylamide (MIP-cryo) were of better stability than the amine containing polymer backbone (Alu-cryo). Both composites worked well in the studied pH range of pH 2-8. Adsorption tested in real wastewater spiked with arsenic showed that co-ions (nitrate, sulphate and phosphate) affected arsenic removal for Alu-cryo more than for MIP-cryo. Both composites still adsorbed well in the presence of counter-ions (copper and zinc) present at low concentrations (μg/l). The unchanged and selective adsorption in realistic water observed for MIP-cryo was concluded to be due to a successful imprinting, here controlled using a non-imprinted polymer (NIP). A development of MIP-cryo is needed, considering its low adsorption capacity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. TESTING OF CARBONACEOUS ADSORBENTS FOR REMOVAL OF POLLUTANTS FROM WATER

    Directory of Open Access Journals (Sweden)

    RAISA NASTAS

    2012-03-01

    Full Text Available Testing of carbonaceous adsorbents for removal of pollutants from water. Relevant direction for improving of quality of potable water is application of active carbons at various stages of water treatments. This work includes complex research dealing with testing of a broad spectrum of carbonaceous adsorbents for removal of hydrogen sulfide and nitrite ions from water. The role of the surface functional groups of carbonaceous adsorbents, their acid-basic properties, and the influence of the type of impregnated heteroatom (N, O, or metals (Fe, Cu, Ni, on removal of hydrogen sulfide species and nitrite ions have been researched. The efficiency of the catalyst obtained from peach stones by impregnation with Cu2+ ions of oxidized active carbon was established, being recommended for practical purposes to remove the hydrogen sulfide species from the sulfurous ground waters. Comparative analysis of carbonaceous adsorbents reveals the importance of surface chemistry for oxidation of nitrite ions.

  8. Treatment of water contaminated with gasoline using red mud as adsorbents; Tratamento de aguas contaminadas com gasolina utilizando lama vermelha como adsorvente

    Energy Technology Data Exchange (ETDEWEB)

    Silva Filho, Ernesto B. da [Universidade Federal de Pernambuco, Recife, PE (Brazil). Dept. de Engenharia Quimica. Lab. de Engenharia Ambiental e da Qualidade; Silva, Paula T.S. e [Universidade Federal de Pernambuco, Recife, PE (Brazil). Dept. de Quimica Fundamental; Campos, Ronaldo J.A. [Universidade Federal de Pernambuco, Recife, PE (Brazil). Dept. de Engenharia Quimica. Lab. de Cromatografia Instrumental; Schuler, Alexandre R.P.; Silva, Valdinete L. da; Motta Sobrinho, Mauricio A. da [Universidade Federal de Pernambuco, Recife, PE (Brazil). Dept. de Engenharia Quimica

    2004-07-01

    The underground or superficial water contamination for oil derivatives, mainly gasoline, has attracted the attention, of the civil society and scientific community in function of the great risks that represent for the environment and the health human. On the other hand, the metallurgical industry has special interest in researches that look for applications commonly for the residue of the improvement of known aluminum as 'red mud'. Such element represents an environmental liability, generating considerable costs for treatment and final disposition adapted. The red mud has characteristics adsorbents thankfully. This work seeks to evaluate the potential of application of the red mud as adsorbent for the separation process between water and oil. In this sense the percentile oil removal was evaluated in a polluted water with gasoline, as well as the effects of the following variables: time of contact (t), amount of used red mud (M), concentration of present oil in the water (Ci) and amount of used polluted water (V) through a planning complete factorial type 24. The results presented here are not conclusive. However one argues which the reasons so that the objectives completely were not reached and if it considers solutions. (author)

  9. Amino-functionalized mesoporous MCM-41 silica as an efficient adsorbent for water treatment: batch and fixed-bed column adsorption of the nitrate anion

    Science.gov (United States)

    Ebrahimi-Gatkash, Mehdi; Younesi, Habibollah; Shahbazi, Afsaneh; Heidari, Ava

    2017-07-01

    In the present study, amino-functionalized Mobil Composite Material No. 41 (MCM-41) was used as an adsorbent to remove nitrate anions from aqueous solutions. Mono-, di- and tri-amino functioned silicas (N-MCM-41, NN-MCM-41 and NNN-MCM-41) were prepared by post-synthesis grafting method. The samples were characterized by means of X-ray powder diffraction, FTIR spectroscopy, thermogravimetric analysis, scanning electron microscopy and nitrogen adsorption-desorption. The effects of pH, initial concentration of anions, and adsorbent loading were examined in batch adsorption system. Results of adsorption experiments showed that the adsorption capacity increased with increasing adsorbent loading and initial anion concentration. It was found that the Langmuir mathematical model indicated better fit to the experimental data than the Freundlich. According to the constants of the Langmuir equation, the maximum adsorption capacity for nitrate anion by N-MCM-41, NN-MCM-41 and NNN-MCM-41 was found to be 31.68, 38.58 and 36.81 mg/g, respectively. The adsorption kinetics were investigated with pseudo-first-order and pseudo-second-order model. Adsorption followed the pseudo-second-order rate kinetics. The coefficients of determination for pseudo-second-order kinetic model are >0.99. For continuous adsorption experiments, NNN-MCM-41 adsorbent was used for the removal of nitrate anion from solutions. Breakthrough curves were investigated at different bed heights, flow rates and initial nitrate anion concentrations. The Thomas and Yan models were utilized to calculate the kinetic parameters and to predict the breakthrough curves of different bed height. Results from this study illustrated the potential utility of these adsorbents for nitrate removal from water solution.

  10. Shrimp pond wastewater treatment using pyrolyzed chicken feather as adsorbent

    Science.gov (United States)

    Moon, Wei Chek; Jbara, Mohamad Hasan; Palaniandy, Puganeshwary; Yusoff, Mohd Suffian

    2017-10-01

    In this study, chicken feather fiber was used as a raw material to prepare a non-expensive adsorbent by pyrolysis without chemical activation. The main pollutants treated in this study were chemical oxygen demand (COD) and ammoniacal nitrogen (NH3-N) from shrimp pond wastewater containing high concentrations of nutrients, which caused the eutrophication phenomenon in adjacent water. Batch adsorption studies were performed to investigate the effect of pH (5-8), mass of adsorbent (0.5-3 g), and shaking time (0.5-2 h) on the removal efficiency of COD and NH3- N. Experimental results showed that the optimum conditions were as follows: pH 5, 0.5 g of adsorbent, and 0.5 h of shaking. Under these conditions, 34.01% and 40.47% of COD and NH3-N were removed, respectively, from shrimp pond wastewater. The adsorption processes were best described by the Langmuir isotherm model for COD and NH3-N removal, with maximum monolayer adsorption capacity of 36.9 and 7.24 mg/g for COD and NH3-N, respectively. The results proved that chicken feather could remove COD and NH3-N from shrimp pond wastewater. However, further studies on thermal treatment should be carried out to increase the removal efficiency of pyrolyzed chicken feather fiber.

  11. Retention of radium from thermal waters on sand filters and adsorbents

    Energy Technology Data Exchange (ETDEWEB)

    Elejalde, C. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain)]. E-mail: inpelsac@bi.ehu.es; Herranz, M. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Legarda, F. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Romero, F. [Dpto. de Ingenieria Quimica y del Medio Ambiente, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Baeza, A. [Dpto. de Fisica, Facultad de Veterinaria, Universidad de Extremadura, Avda. Universidad s/n, 10071 Caceres (Spain)

    2007-06-18

    This study was focussed on laboratory experiences of retention of radium from one thermal water on sand filters and adsorbents, trying to find an easy method for the elimination in drinkable waters polluted with this natural radio-nuclide. A thermal water from Cantabria (Spain) was selected for this work. Retention experiences were made with columns of 35 mm of diameter containing 15 cm layers of washed river sand or 4 cm layers of zeolite A3, passing known volumes of thermal water at flows between 4 and 40 ml/min with control of the retained radium by determining the amount in the water after the treatment. The statistical analysis of data suggests that retention depends on the flow and the volume passed through the columns. As additional adsorbents were used kaolin and a clay rich in illite. Jar-test experiences were made agitating known weights of adsorbents with the selected thermal water, with addition of flocculants and determination of radium in filtrated water after the treatment. Data suggest that retention is related to the weight of adsorbent used, but important quantities of radium seem remain in solution for higher amounts of adsorbents, according to the statistical treatment of data. The elution of retained radium from columns or adsorbents, previously used in experiences, should be the aim of a future research.

  12. Water Purification Using Functionalized Cellulosic Fibers with Nonleaching Bacteria Adsorbing Properties.

    Science.gov (United States)

    Ottenhall, Anna; Illergård, Josefin; Ek, Monica

    2017-07-05

    Portable purification systems are easy ways to obtain clean drinking water when there is no large-scale water treatment available. In this study, the potential to purify water using bacteria adsorbing cellulosic fibers, functionalized with polyelectrolytes according to the layer-by-layer method, is investigated. The adsorbed polyelectrolytes create a positive charge on the fiber surface that physically attracts and bonds with bacteria. Three types of cellulosic materials have been modified and tested for the bacterial removal capacity in water. The time, material-water ratio and bacterial concentration dependence, as well as the bacterial removal capacity in water from natural sources, have been evaluated. Freely dispersed bacteria adsorbing cellulosic fibers can remove greater than 99.9% of Escherichia coli from nonturbid water, with the most notable reduction occurring within the first hour. A filtering approach using modified cellulosic fibers is desirable for purification of natural water. An initial filtration test showed that polyelectrolyte multilayer modified cellulosic fibers can remove greater than 99% of bacteria from natural water. The bacteria adsorbing cellulosic fibers do not leach any biocides, and it is an environmentally sustainable and cheap option for disposable water purification devices.

  13. Early molecular adsorbents recirculating system treatment of Amanita mushroom poisoning.

    Science.gov (United States)

    Kantola, Taru; Kantola, Teemu; Koivusalo, Anna-Maria; Höckerstedt, Krister; Isoniemi, Helena

    2009-10-01

    Acute poisoning due to ingestion of hepatotoxic Amanita sp. mushrooms can result in a spectrum of symptoms, from mild gastrointestinal discomfort to life-threatening acute liver failure. With conventional treatment, Amanita phalloides mushroom poisoning carries a substantial risk of mortality and many patients require liver transplantation. The molecular adsorbent recirculating system (MARS) is an artificial liver support system that can partly compensate for the detoxifying function of the liver by removing albumin-bound and water-soluble toxins from blood. This treatment has been used in acute liver failure to enable native liver recovery and as a bridging treatment to liver transplantation. The aim of the study is to evaluate the outcome of 10 patients with Amanita mushroom poisoning who were treated with MARS. The study was a retrospectively analyzed case series. Ten adult patients with accidental Amanita poisoning of varying severity were treated in a liver disease specialized intensive care unit from 2001 to 2007. All patients received MARS treatment and standard medical therapy for mushroom poisoning. The demographic, laboratory, and clinical data from each patient were recorded upon admission. The one-year survival and need for liver transplantation were documented. The median times from mushroom ingestion to first-aid at a local hospital and to MARS treatment were 18 h (range 14-36 h) and 48 h (range 26-78 h), respectively. All 10 patients survived longer than one year. One patient underwent a successful liver transplantation. No serious adverse side-effects were observed with the MARS treatment. In conclusion, MARS treatment seems to offer a safe and effective treatment option in Amanita mushroom poisoning.

  14. Organobentonites as multifunctional adsorbents of organic and inorganic water pollutants

    Directory of Open Access Journals (Sweden)

    Jović-Jovičić Natаša

    2014-01-01

    Full Text Available The aim of this study was to find a low cost, easy to synthesize and efficient adsorbent for the simultaneous adsorption of both organic and inorganic pollutants (including textile dyes, toxic metals etc.. The starting material, domestic bentonite clay from Bogovina was modified with amounts of hexadecyltrimethylammonium cations corresponding to 0.5 and 1.0 times of the value of the cation exchange capacity value. The organobentonites were tested as adsorbents in a three-dye-containing solution, a three-component solution of Pb2+, Cd2+ and Ni2+ and a hexa- component solution containing all investigated dyes and toxic metal cations. The used adsorbents showed the highest affinity toward Acid Yellow 99 and Ni2+ ions. Dye adsorption was enhanced in the presence of toxic metal cations, while the adsorption of all toxic cations from the hexa-component solution was lower than from the three-component solution containing only toxic cations. The synthesized hexadecyltrimethylammonium bentonite could be regarded as an efficient multifunctional adsorbent for the investigated type of water pollutants.

  15. Removal of arsenic from drinking water by natural adsorbents

    OpenAIRE

    MD SHAHNOOR ALAM KHAN

    2017-01-01

    The presence of arsenic in groundwater has been reported in many countries across the world and it is a serious threat to public health. The aim of this study was to identify prospective natural materials with high arsenic adsorption capacity and durable hydraulic property to produce adequate flow of water. The comparative study identified Skye sand as the best natural adsorbent. The prototype household filter with Skye sand achieved complete removal of arsenic and iron. Arsenic removal by du...

  16. Radiolytic stability of gibbsite and boehmite with adsorbed water

    Energy Technology Data Exchange (ETDEWEB)

    Huestis, Patricia; Pearce, Carolyn I.; Zhang, X.; N' Diaye, Alpha T.; Rosso, Kevin M.; LaVerne, Jay A.

    2018-04-01

    Aluminum oxyhydroxide (boehmite, AlOOH) and aluminum hydroxide (gibbsite, Al(OH)3) powders with adsorbed water were irradiated with -rays and 5 MeV He ions (α-particles) in order to determine overall radiation stability and chemical modification to the surface. No variation in overall phase or crystallinity due to radiolysis was observed with X-ray diffraction (XRD) and Raman spectroscopy for doses up to 2 MGy with -rays and 175 MGy with α-particles. Temperature programed desorption (TPD) of the water from the surface to the gas phase indicated that the water was chemisorbed and strongly bound. Water adsorption sites are of similar energy for both gibbsite and boehmite. Observation of the water adsorbed on the surface of gibbsite and boehmite with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) showed broad peaks at 3100-3600 cm-1 due to OH stretching that slowly decreased on heating to 500oC, which corresponds well with the water vapor evolution observed with TPD. Both materials were found to be amorphous following heating to 500oC. X-ray photoelectron spectroscopy (XPS) indicated surface reduction of Al(III) to Al metal on radiolysis with α-particles. Complete loss of chemisorbed water and the formation of bulk O atoms was observed following radiolysis with α-particles.

  17. The Potential Characteristics Of Adsorbed Water At The Lunar Poles

    Science.gov (United States)

    Hibbitts, Charles A.; Dyar, D.; Orlando, T.

    2009-09-01

    Hydrogen can be trapped in the surface of the moon through a variety of processes and from many different origins. Solar wind particles may explain a portion of the elevated hydrogen abundance at the lunar poles, and could react with the regolith to form water ions (OH-) (Starukhina and Shkuratov, 2000). A few layers of molecular water, such as from cometary impacts, could be thermodynamically stable at the poles (e.g. Cocks et al., 2002) although Eschelman and Parks (1999) predict that initially molecular water would be sufficiently mobile in the sunlit regions to eventually chemically bond to the regolith grains. Previous laboratory experiments support this premise, demonstrating that monolayer water forms OH- with Temperature-Programmed Desorption (TPD) analyses showing a monolayer (of OH-) on TiO2 is stable below 295K, two layers are stable below 195K, and more layers form water ice (Lane et al., 2009). Water ice can exist on the Moon, but only in the cold portions of permanently-shadowed craters (Watson et al.,1961, Vasavada et al., 1999). Even here, though, the water may exist as individually adsorbed molecules unable to migrate to form ice grains because the molecules are immobilized by the cold temperatures and electrostatic bonding to the regolith grains (Hibbitts et al., 2009). The spectral characteristics and observable strengths of the 3-micron fundamental (strongest) absorption feature are specific to these forms of `water’ and one or two layers on lunar regolith grains should have a detectable 3-micron feature given the regolith's effective surface area of 1m2/g (Cadenhead, 1972). The absorption band in water-ice is narrow positioned 3.1 microns, water is broad 2.9 microns, and the band associated with adsorbed water varies with physical state and temperature from 2.8 microns to 3 microns. This work is funded by the NASA LASER progam.

  18. Utility of adsorbents in the purification of drinking water: a review of characterization, efficiency and safety evaluation of various adsorbents.

    Science.gov (United States)

    Dubey, Shashi Prabha; Gopal, Krishna; Bersillon, J L

    2009-05-01

    Clean drinking water is one of the implicit requisites fora healthy human population. However the growing industrialization and extensive use of chemicals for various concerns, has increased the burden of unwanted pollutants in the drinking water of developing countries like India. The entry of potentially hazardous substances into the biota has been magnifying day by day. In the absence of a possible stoppage of these, otherwise, useful chemicals, the only way to maintain safer water bodies is to develop efficient purifying technologies. One such immensely beneficial procedure that has been in use is that of purification of water using 'adsorbents'. Indigenous minerals and natural plants products have potential for removing many pollutants viz. fluoride, arsenic, nitrate, heavy metals, pesticides as well as trihalomethanes. Adsorbents which are derived from carbon, alumina, zeolite, clay minerals, iron ores, industrial by products, and natural products viz. parts of the plants, herbs and algal biomass offer promising potential of removal. In the recent years attention has been paid to develop process involving screening/pretreatment/activation/impregnation using alkalies, acids, alum, lime, manganese dioxide, ferric chloride and other chemicals which are found to enhance their adsorbing efficiency. Chemical characterization of these adsorbents recapitulates the mechanism of the process. It is imperative to observe that capacities of the adsorbents may vary depending on the characteristics, chemical modifications and concentration of the individual adsorbent. Removal kinetics is found to be based on the experimental conditions viz. pH, concentration of the adsorbate, quantity of the adsorbent and temperature. It is suggested that isotherm model is suitable tool to assess the adsorption capacities in batch and column modes. Safety evaluation and risk assessment of the process/products may be useful to provide guidelines for its sustainable disposal.

  19. Synthesis and properties of a high-capacity iron oxide adsorbent for fluoride removal from drinking water

    Science.gov (United States)

    Zhang, Chang; Li, Yingzhen; Wang, Ting-Jie; Jiang, Yanping; Fok, Jason

    2017-12-01

    A novel iron oxide adsorbent with a high fluoride adsorption capacity was prepared by a facile wet-chemical precipitation method and ethanol treatment. The ethanol-treated adsorbent was amorphous and had a high specific surface area. The adsorption capacity of the treated adsorbent was much higher than that of untreated adsorbent. The Langmuir maximum adsorption capacity of the adsorbent prepared at a low final precipitation pH (≤9.0) and treated with ethanol reached 60.8 mg/g. A fast adsorption rate was obtained, and 80% of the adsorption equilibrium capacity was achieved within 2 min. The adsorbent had high fluoride-removal efficiency for water in a wide initial pH range of 3.5-10.3 and had a high affinity for fluoride in the presence of common co-anions. The ethanol treatment resulted in structure transformation of the adsorbent by inhibiting the crystallization of the nano-precipitates. The adsorption was confirmed to be ion exchange between fluoride ions and the hydroxyl groups on the adsorbent surface.

  20. Development of a Household Water Defluoridation Process Using Aluminium Hydroxide Based Adsorbent.

    Science.gov (United States)

    Mulugeta, Eyobel; Zewge, Feleke; Chandravanshi, Bhagwan Singh

    2015-06-01

    In this study, the removal of fluoride from water using aluminium hydroxide based adsorbent has been investigated in continuous operation. The effect of fluoride influent concentration, feed flowrate, and adsorbent bed height onto the breakthrough characteristics of the adsorption system were examined. The fixed-bed adsorption system was found to perform better with lower influent fluoride concentration, lower flowrate, and higher bed depth. Thermodynamic evaluation using the bed depth service time model indicated that the fluoride adsorption capacity was 25.8 mg F-/g of adsorbent, which is high compared to commercially available activated alumina (1.8 to 1.9 mg/g). Kinetic studies showed that the rate of adsorption in continuous studies was in the range of 6.12×10(-3) to 39.3×10(-3) L/mg.h under different operating conditions. The household defluoridation unit (HDU) was tested at an up-flow mode and it was determined that the HDU packed with 0.9 kg of adsorbent with 28.3 cm of bed depth resulted in a specific safe water yield of 823.79 L. Regeneration of the exhaust media using 1% NaOH and 0.1 M HCl showed that the adsorbent could be reused. The estimated running cost of the unit was 2.0 U.S. dollar/m3 of treated water, with the potential to minimize further. Hence, it was concluded that the proposed method is simple and exhibits superior performance for the treatment of fluoride-contaminated water with the potential for household application.

  1. The application of Fe–Mn hydrous oxides based adsorbent for removing selenium species from water

    KAUST Repository

    Szlachta, Małgorzata

    2013-02-01

    In this study, the adsorptive removal of selenium(IV) and selenium(VI) from water by a newly developed ion exchange adsorbent, based on Fe(III) and Mn(III) hydrous oxides, was examined. This study was conducted to determine the influence of various operating parameters, such as initial anion concentration, contact time, adsorbent dose, pH, solution temperature, and the presence of competitive anions, on the treatment performance. The high Se(IV) adsorptive capacity of the adsorbent (up to 41.02. mg/g at pH 4) was due to its high affinity for selenite, as reflected in the fast rate of uptake (batch studies) and an efficient long-term removal (column experiments). Although adsorption of anions traditionally decreases as pH increases, the mixed adsorbent was capable of purifying large volumes of Se(IV)-containing water (at pH 7) to reach concentrations lower than 10 μg/L, which meets the European Commission standards. The presence of sulphate and carbonate did not influence Se(IV) adsorption. However, high phosphate and silicate concentrations may have decreased the removal efficiency of Se(IV). Data from the batch and column adsorption experiments were fitted with a number of approved models, which revealed the adsorption mechanism and allowed for a comparison of the results. © 2012 Elsevier B.V.

  2. Arsenic removal from water using a novel amorphous adsorbent developed from coal fly ash.

    Science.gov (United States)

    Zhang, Kaihua; Zhang, Dongxue; Zhang, Kai

    2016-01-01

    A novel effective adsorbent of alumina/silica oxide hydrate (ASOH) for arsenic removal was developed through simple chemical reactions using coal fly ash. The iron-modified ASOH with enhancing adsorption activity was further developed from raw fly ash based on the in situ technique. The adsorbents were characterized by X-ray diffraction, Fourier transform infrared spectrometry, scanning electron micrograph, laser particle size and Brunauer-Emmet-Teller surface area. The results show that the adsorbents are in amorphous and porous structure, the surface areas of which are 8-12 times that of the raw ash. The acidic hydrothermal treatment acts an important role in the formation of the amorphous structure of ASOH rather than zeolite crystal. A series of adsorption experiments for arsenic on them were studied. ASOH can achieve a high removal efficiency for arsenic of 96.4% from water, which is more than 2.5 times that of the raw ash. Iron-modified ASOH can enhance the removal efficiency to reach 99.8% due to the in situ loading of iron (Fe). The condition of synthesis pH = 2-4 is better for iron-modified ASOH to adsorb arsenic from water.

  3. The Microscopic Structure of Adsorbed Water on Hydrophobic Surfaces under Ambient Conditions

    OpenAIRE

    Cao, Peigen; Xu, Ke; Varghese, Joseph O.; Heath, James R.

    2011-01-01

    The interaction of water vapor with hydrophobic surfaces is poorly understood. We utilize graphene templating to preserve and visualize the microscopic structures of adsorbed water on hydrophobic surfaces. Three well-defined surfaces [H–Si(111), graphite, and functionalized mica] were investigated, and water was found to adsorb as nanodroplets (~10–100 nm in size) on all three surfaces under ambient conditions. The adsorbed nanodroplets were closely associated with atomic-scale surface defect...

  4. Eliminating Heavy Metals from Water with NanoSheet Minerals as Adsorbents

    Directory of Open Access Journals (Sweden)

    Shaoxian Song

    2017-12-01

    Full Text Available Heavy metals usually referred to those with atomic weights ranging from 63.5 to 200.6. Because of natural-mineral dissolution and human activities such as mining, pesticides, fertilizer, metal planting and batteries manufacture, etc., these heavy metals, including zinc, copper, mercury, lead, cadmium and chromium have been excessively released into water courses, like underground water, lake and river, etc. The ingestion of the heavy metals-contaminated water would raise serious health problems to human beings even at a low concentration. For instance, lead can bring human beings about barrier to the normal function of kidney, liver and reproductive system, while zinc can cause stomach cramps, skin irritations, vomiting and anemia. Mercury is a horrible neurotoxin that may result in damages to the central nervous system, dysfunction of pulmonary and kidney, chest and dyspnea. Chromium (VI has been proved can cause many diseases ranging from general skin irritation to severe lung carcinoma. Accordingly, the World Health Organization announced the maximum contaminant levels (MCL for the heavy metals in drinking water. There are numerous processes for eliminating heavy metals from water in order to provide citizens safe drinking water, including precipitation, adsorption, ion exchange, membrane separation and biological treatment, etc. Adsorption is considered as a potential process for deeply removing heavy metals, in which the selection of adsorbents plays a predominant role. Nano-sheet minerals as the adsorbents are currently the hottest researches in the field. They are obtained from layered minerals, such as montmorillonite, graphite and molybdenite, through the processing of intercalation, electrochemical and mechanical exfoliation, etc. Nano-sheet minerals are featured by their large specific surface area, relatively low costs and active adsorbing sites, leading to be effective and potential adsorbents for heavy metals removal from water

  5. WATER TREATMENT

    Science.gov (United States)

    Pitman, R.W.; Conley, W.R. Jr.

    1962-12-01

    An automated system for adding clarifying chemicals to water in a water treatment plant is described. To a sample of the floc suspension polyacrylamide or similar filter aid chemicals are added, and the sample is then put through a fast filter. The resulting filtrate has the requisite properties for monitoring in an optical turbidimeter to control the automated system. (AEC)

  6. Arsenic removal from water using low-cost adsorbents: A comparative study

    Directory of Open Access Journals (Sweden)

    Rajaković Ljubinka V.

    2011-01-01

    Full Text Available Inorganic arsenic removal from water using low-cost adsorbents is presented in this paper. Selective removal of As(III and As(V from water was performed with natural materials (zeolite, bentonite, sepiolite, pyrolusite and limonite and industrial by-products (waste filter sand as a water treatment residual and blast furnace slag from steel production; all inexpensive and locally available. Kinetic and equilibrium studies were realized using batch system techniques under conditions that are likely to occur in real water treatment systems. The natural zeolite and the industrial by-products were found to be good and inexpensive sorbents for arsenic while bentonite and sepiolite clays showed little affinity towards arsenic. The highest maximum sorption capacities were obtained for natural zeolite, 4.07 mg As(V g-1, and waste iron slag, 4.04 mg As(V g-1.

  7. Structure and dynamics of egg white ovalbumin adsorbed at the air/water interface

    NARCIS (Netherlands)

    Kudryashova, E.V.; Meinders, M.B.J.; Visser, A.J.W.G.; Hoek, A. van; Jongh, H.H.J. de

    2003-01-01

    The molecular properties of egg white ovalbumin adsorbed at the air/water interface were studied using infrared reflection absorption spectroscopy (IRRAS) and time-resolved fluorescence anisotropy (TRFA) techniques. Ovalbumin adsorbed at the air/ water interface adopts a characteristic partially

  8. Structure and dynamics of egg white ovalbumin adsorbed at the air/water interface

    NARCIS (Netherlands)

    Kudryashova, E.V.; Meinders, M.B.J.; Visser, A.J.W.G.; Hoek, van A.; Jongh, de H.H.J.

    2003-01-01

    The molecular properties of egg white ovalbumin adsorbed at the air/water interface were studied using infrared reflection absorption spectroscopy (IRRAS) and time-resolved fluorescence anisotropy (TRFA) techniques. Ovalbumin adsorbed at the air/water interface adopts a characteristic partially

  9. Selection and evaluation of adsorbents for the removal of anionic surfactants from laundry rinsing water

    NARCIS (Netherlands)

    Schouten, N.; van der Ham, Aloysius G.J.; Euverink, Gert-Jan W.; de Haan, A.B.

    2007-01-01

    Low-cost adsorbents were tested to remove anionic surfactants from laundry rinsing water to allow re-use of water. Adsorbents were selected corresponding to the different surfactant adsorption mechanisms. Equilibrium adsorption studies of linear alkyl benzene sulfonate (LAS) show that ionic

  10. Nanostructured Block Polymer Membranes as High Capacity Adsorbers for the Capture of Metal Ions from Water

    Science.gov (United States)

    Boudouris, Bryan; Weidman, Jacob; Mulvenna, Ryan; Phillip, William

    The efficient removal of metal ions from aqueous streams is of significant import in applications ranging from industrial waste treatment to the purification of drinking water. An emerging paradigm associated with this separation is one that utilizes membrane adsorbers as a means by which to bind metal salt contaminants. Here, we demonstrate that the casting of an A-B-C triblock polymer using the self-assembly and non-solvent induced phase separation (SNIPS) methodology results in a nanoporous membrane geometry. The nature of the triblock polymer affords an extremely high density of binding sites within the membrane. As such, we demonstrate that the membranes with binding capacities equal to that of state-of-the-art packed bed columns. Moreover, because the affinity of the C moiety can be tuned, highly selective binding events can occur based solely on the chemistry of the block polymer and the metal ions in solution (i.e., in a manner that is independent of the size of the metal ions). Due to these combined facts, these membranes efficiently remove heavy metal (e.g., lead- and cadmium-based) salts from contaminated water streams with greater than 95% efficiency. Finally, we show that the membranes can be regenerated through a simple treatment in order to provide long-lasting adsorber systems as well. Thus, it is anticipated that these nanostructured triblock polymer membranes are a platform by which to obtain next-generation water purification processes.

  11. Comparision of Chitosan Function as Adsorbent for Nitrate Removal Using Synthetic Aqueous Solution and Drinking Water

    Directory of Open Access Journals (Sweden)

    Mohammad Norisepehr

    2013-12-01

    Full Text Available Background & Objectives: Nitrate and nitrite compounds pollution of groundwater resources in recent years which recently their mean concentration due to enhancement of different kind of municipal, industrial and agriculture waste water, were increased. The most common source of nitrates entering the water include chemical fertilizers and animal manure in agriculture, septic tank effluent, wastewater, wastewater treatment plants, animal and plant residue analysis on the ground of non-sanitary disposal of solid waste and the use of absorbing wells for sewage disposal. Materials and methods: This experimental study is applied to the nitrate removal using chitosan in laboratory scale at ambient temperature and the design of the system was Batch. Effects of parameters such as pH, contact time, initial concentration and adsorbent concentration of nitrate on nitrate removal from aqueous solution was studied. Results: Function of chitosan in synthetic aqueous solution and drinking water according to the slurry system results, the optimum condition was obtained at pH=4, 20 min contact time and increasing the initial concentration of nitrate enhance the adsorption capacity of chitosan. Also optimum dosage of adsorbent was obtained at 0.5 g/l. The data obtained from the experiments of adsorbent isotherm were analyzed using Langmuir and Freundlich isotherm models. The Langmuir equation was found to be the best fitness with the experimental data (R2>0.93. Conclusion: Although efficiency of Nitrate removal in synthetic aqueous solution was better than drinking water, adsorption process using chitosan as an option for the design and selection nitrate removal should be considered in order to achieve environmental standards.

  12. Metal-modified silica adsorbents for removal of humic substances in water.

    Science.gov (United States)

    Moriguchi, Takeshi; Yano, Kazuyuki; Tahara, Muneaki; Yaguchi, Kazuhiko

    2005-03-15

    As novel adsorbents for humic substances, Fe-, Mg-, and Ca-modified silica gels SiO(2)Fe, SiO(2)Mg, and SiO(2)Ca were prepared, and their adsorbabilities to humic and fulvic acids were evaluated in water at 25 degrees C for 20 h. Among these adsorbents, SiO(2)Fe indicated the highest adsorbability, in which removing humic substances in water was accomplished to 80-97%. By calcination at 600 degrees C and washing with water, adsorbabilities of the silica adsorbents deteriorated except for the case of calcination of SiO(2)Ca. This is due to changing metal modification structures and losing chlorine, judging from elemental analysis, TG-DTA, and XPS. Especially, the modifier Fe was tightly fixed on the silica surface of SiO(2)Fe, since the metal content was almost constant even after the calcination and water washing unlike the other adsorbents. Therefore, we found that SiO(2)Fe is the most useful adsorbent among the silica adsorbents and that its modification structure is composed of SiOFe, FeCl, and FeOH. In addition, the adsorption mechanism is explained by an interaction between Fe and humic substance molecule having carboxylate and phenolate groups, accompanied with anion exchange of chloride ion Cl(-) for the humic substance molecule via the silica pores. SiO(2)Fe may be applied to an adsorbent alternative for charcoal in water purification plants, and the used SiO(2)Fe may be further reused as a fertilizer since humic substances have plant-glowing ability and silica strengthens plant parts.

  13. Evaluating of arsenic(V) removal from water by weak-base anion exchange adsorbents.

    Science.gov (United States)

    Awual, M Rabiul; Hossain, M Amran; Shenashen, M A; Yaita, Tsuyoshi; Suzuki, Shinichi; Jyo, Akinori

    2013-01-01

    Arsenic contamination of groundwater has been called the largest mass poisoning calamity in human history and creates severe health problems. The effective adsorbents are imperative in response to the widespread removal of toxic arsenic exposure through drinking water. Evaluation of arsenic(V) removal from water by weak-base anion exchange adsorbents was studied in this paper, aiming at the determination of the effects of pH, competing anions, and feed flow rates to improvement on remediation. Two types of weak-base adsorbents were used to evaluate arsenic(V) removal efficiency both in batch and column approaches. Anion selectivity was determined by both adsorbents in batch method as equilibrium As(V) adsorption capacities. Column studies were performed in fixed-bed experiments using both adsorbent packed columns, and kinetic performance was dependent on the feed flow rate and competing anions. The weak-base adsorbents clarified that these are selective to arsenic(V) over competition of chloride, nitrate, and sulfate anions. The solution pH played an important role in arsenic(V) removal, and a higher pH can cause lower adsorption capacities. A low concentration level of arsenic(V) was also removed by these adsorbents even at a high flow rate of 250-350 h(-1). Adsorbed arsenic(V) was quantitatively eluted with 1 M HCl acid and regenerated into hydrochloride form simultaneously for the next adsorption operation after rinsing with water. The weak-base anion exchange adsorbents are to be an effective means to remove arsenic(V) from drinking water. The fast adsorption rate and the excellent adsorption capacity in the neutral pH range will render this removal technique attractive in practical use in chemical industry.

  14. The development of an adsorbent for corrosion products in high-temperature water

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Ik; Sung, Ki Woung; Kim, Kwang Rag; Kim, Yu Hwan; Koo, Jae Hyoo [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1996-08-01

    In order to use as adsorbent for removal of the soluble corrosion products, mainly Co{sup 60} under PWR reactor coolant conditions (300 deg C, 160 kg/cm{sup 2}), stable ZrO{sub 2} adsorbent was prepared using sol-gel process from zirconyl nitrate, AlO adsorbent was prepared by hydrolysis of aluminum isopropoxide, and titanium tetraisopropoxide, respectively. The prepared adsorbents were calcined at various temperature and analyzed by physical properties and the Co{sup 2+} adsorption capacity. And it was shown that the Co{sup 2+} adsorption capacity of the TiO{sub 2}-Al{sub 2}O{sub 3} adsorbents were found to have larger than that of ZrO{sub 2} and Al{sub 2}O{sub 3} adsorbents in high-temperature water. ZrO{sub 2}, Al{sub 2}O{sub 3} and TiO{sub 2}-Al{sub 2}O{sub 3} adsorbents were found to be suitable high-temperature adsorbents for the removal of dissolved corrosion products, mainly Co in PWR reactor coolant conditions. 15 tabs., 51 figs., 55 refs. (Author).

  15. Removal of Heavy Metal Ions from Polluted Waters by Using of Low Cost Adsorbents: Review

    Directory of Open Access Journals (Sweden)

    M. Ghaedi

    2013-06-01

    Full Text Available Adsorption is a fundamental process in the physicochemical treatment of wastewaters which industries employ to reduce hazardous organic and inorganic wastes in effluents. In recent years the use of low-cost adsorbents has been widely investigated as a replacement for the currently costly methods of removing heavy metal ions from wastewater. It is well-known that cellulosic waste materials can be obtained and employed as cheap adsorbents and their performance to remove heavy metal ions can be affected upon chemical treatment. In this study, the use of some of low cost adsorbents for the removal of heavy metals from wastewater has been reviewed.

  16. Effect of adsorbents and chemical treatments on the removal of strontium from aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Ahmadpour, A., E-mail: ahmadpour@um.ac.ir [Department of Chemical Engineering, Faculty of Engineering, Ferdowsi University of Mashhad, 9177948944 Mashhad (Iran, Islamic Republic of); Zabihi, M. [Department of Chemical Engineering, Faculty of Engineering, Ferdowsi University of Mashhad, 9177948944 Mashhad (Iran, Islamic Republic of); Tahmasbi, M.; Bastami, T. Rohani [Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad (Iran, Islamic Republic of)

    2010-10-15

    In the present investigation, three different solid wastes namely almond green hull, eggplant hull, and moss were initially treated and used as adsorbents for the adsorption of strontium ion from aqueous solutions. Adsorbent types and chemical treatments are proved to have effective roles on the adsorption of Sr(II) ion. Among the three adsorbents, almond green hull demonstrated strong affinity toward strontium ion in different solutions. The effectiveness of this new adsorbent was studied in batch adsorption mode under a variety of experimental conditions such as: different chemical treatments, various amounts of adsorbent, and initial metal-ion concentration. The optimum doses of adsorbent for the maximum Sr(II) adsorption were found to be 0.2 and 0.3 g for 45 and 102 mg L{sup -1} solutions, respectively. High Sr(II) adsorption efficiencies were achieved only in the first 3 min of adsorbent's contact time. The kinetics of Sr(II) adsorption on almond green hull was also examined and it was observed that it follows the pseudo second-order behavior. Both Langmuir and Freundlich models well predicted the experimental adsorption isotherm data. The maximum adsorption capacity on almond green hull was found to be 116.3 mg g{sup -1}. The present study also confirmed that these low cost agriculture byproducts could be used as efficient adsorbents for the removal of strontium from wastewater streams.

  17. Selenium Adsorption To Aluminum-Based Water Treatment Residuals

    Science.gov (United States)

    Aluminum-based water treatment residuals (WTR) can adsorb water-and soil-borne P, As(V), As(III), and perchlorate, and may be able to adsorb excess environmental selenium. WTR, clay minerals, and amorphous aluminum hydroxide were shaken for 24 hours in selenate or selenite solut...

  18. Microwave assisted thermal treatment of defective coffee beans press cake for the production of adsorbents.

    Science.gov (United States)

    Franca, Adriana S; Oliveira, Leandro S; Nunes, Anne A; Alves, Cibele C O

    2010-02-01

    Defective coffee press cake, a residue from coffee oil biodiesel production, was evaluated as an adsorbent for removal of basic dyes (methylene blue--MB) from aqueous solutions. The adsorbent was prepared by microwave treatment, providing a significant reduction in processing time coupled to an increase in adsorption capacity in comparison to conventional carbonization in a muffle furnace. Batch adsorption tests were performed at 25 degrees C and the effects of particle size, contact time, adsorbent dosage and initial solution pH were investigated. Adsorption kinetics was better described by a second-order model. The experimental adsorption equilibrium data were fitted to Langmuir, Freundlich and Tempkin adsorption models, with Langmuir providing the best fit. The results presented in this study show that microwave activation presents great potential as an alternative method in the production of adsorbents.

  19. A Novel Nanohybrid Nanofibrous Adsorbent for Water Purification from Dye Pollutants

    DEFF Research Database (Denmark)

    Homaeigohar, Shahin; Zillohu, Ahnaf; Abdelaziz, Ramzy

    2016-01-01

    In this study, we devised a novel nanofibrous adsorbent made of polyethersulfone (PES) for removal of methylene blue (MB) dye pollutant from water. The polymer shows a low isoelectric point thus at elevated pHs and, being nanofibrous, can offer a huge highly hydroxylated surface area for adsorption...

  20. Simulation of adsorber tube diameter's effect on new design silica gel-water adsorption chiller

    Science.gov (United States)

    Nasruddin, Taufan, A.; Manga, A.; Budiman, D.

    2017-03-01

    A new design of silica gel-water adsorption chiller is proposed. The design configuration is composed of two sorption chambers with compact fin tube heat exchangers as adsorber, condenser, and evaporator. Heat and mass recovery were adopted in order to increase the cooling capacity. Numerical modelling and calculation were used to show the performance of the chiller with different adsorber tube diameter. Under typical condition for hot water inlet/cooling water inlet/chilled water outlet temperatures are 90/30/7°C, respectively, the simulation results showed the best average value of COP, SCP, and cooling power are 0.19, 15.88 W/kg and 279.89 W using 3/8 inch tube.

  1. Copper ions removal from water using functionalized carbon nanotubes–mullite composite as adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Tofighy, Maryam Ahmadzadeh; Mohammadi, Toraj, E-mail: torajmohammadi@iust.ac.ir

    2015-08-15

    Highlights: • CNTs–mullite composite was prepared via chemical vapor deposition (CVD) method. • The prepared composite was modified with concentrated nitric acid and chitosan. • The modified CNTs–mullite composites were used as novel adsorbents. • Copper ion removal from water by the prepared adsorbents was performed. • Langmuir and Freundlich isotherms and two kinetic models were applied to fit the experimental data. - Abstract: Carbon nanotubes–mullite composite was synthesized by direct growth of carbon nanotubes on mullite particles via chemical vapor deposition method using cyclohexanol and ferrocene as carbon precursor and catalyst, respectively. The carbon nanotubes–mullite composite was oxidized with concentrated nitric acid and functionalized with chitosan and then used as a novel adsorbent for copper ions removal from water. The results demonstrated that modification with concentrated nitric acid and chitosan improves copper ions adsorption capacity of the prepared composite, significantly. Langmuir and Freundlich isotherms and two kinetic models were applied to fit the experimental data. The carbon nanotubes growth on mullite particles to form the carbon nanotubes–mullite composite with further modification is an inherently safe approach for many promising environmental applications to avoid some concerns regarding environment, health and safety. It was found that the modified carbon nanotubes–mullite composite can be considered as an excellent adsorbent for copper ions removal from water.

  2. [Characteristics and comparative study of a new drinking-water defluoridation adsorbent Bio-F].

    Science.gov (United States)

    Zhu, Chi; Zhao, Liang-Yuan; Yuan, Heng; Yang, Han-Ying; Li, Ang; Wang, Peng; Yang, Shao

    2009-04-15

    To evaluate the application potentiality pf a new type drinking-water defluoridation adsorbent Bio-F, comparative study on the defluoridation characteristics of common adsorbents activated alumina (AA), bone char (BC), activated clinoptilolite (AC) with Bio-F was conducted. The defluoridation characteristics under different conditions, such as particle diameter, pH, retention time, fluorine concentration, regeneration stability, were investigated by continuous-flow column experiments and static tests. The defluoridation efficiency of high fluoride underground water by four types of adsorbents was also compared. The results showed that F(-) adsorption kinetics of Bio-F fitted the Lagergren First-order equation (R2 = 0.9580). F(-) adsorption by Bio-F was found to fit the Langmuir adsorption isotherm (R2 = 0.9992). The results indicated that the static defluoridation capacity (DC) of Bio-F was 4.0883 mg x g(-1), which was about 1.8 folds and 5.8 folds of those of AA and AC respectively. DC of all four adsorbents was positively correlated with F(-) concentration and negatively correlated with particle size. High concentration of CO3(2-) and HCO3(-) reduced the DC of Bio-F (p defluoridation by Bio-F (p water defluoridation.

  3. Water Treatment Group

    Data.gov (United States)

    Federal Laboratory Consortium — This team researches and designs desalination, water treatment, and wastewater treatment systems. These systems remediate water containing hazardous c hemicals and...

  4. Influence of Adsorbed Water on the Oxygen Evolution Reaction on Oxides

    DEFF Research Database (Denmark)

    Siahrostami, Samira; Vojvodic, Aleksandra

    2015-01-01

    We study the interface between adsorbed water and stoichiometric, defect-free (110) rutile oxide surfaces of TiO2, RuO2, and IrO2 in order to understand how water influences the stabilities of the intermediates of the oxygen evolution reaction (OER). In our model the water is treated as explicitly...... molecules binding to bridging oxygens. The third chain interacts weakly and predominantly with the H2O molecules of the second layer, resembling bulk water. We find that the stability of the water layer close to the oxide surface is almost the same as the one found on flat metal surfaces, such as the Pt(111...... adsorbed H2O molecules, which are found to form two-dimensional water chains (layers) on all investigated oxide surfaces. The first chain formed by the most strongly bound H2O molecules is adsorbed on the 5-fold coordinated surface metal atoms. The second chain is composed of less strongly bound H2O...

  5. A review of emerging adsorbents and current demand for defluoridation of water: Bright future in water sustainability.

    Science.gov (United States)

    Yadav, Krishna Kumar; Gupta, Neha; Kumar, Vinit; Khan, Shakeel Ahmad; Kumar, Amit

    2018-02-01

    Fluoride contamination of groundwater is a serious problem in several countries of the world because of the intake of excessive fluoride caused by the drinking of the contaminated groundwater. Geological and anthropogenic factors are responsible for the contamination of groundwater with fluoride. Excess amounts of fluoride in potable water may cause irreversible demineralisation of bone and tooth tissues, a condition called fluorosis, and long-term damage to the brain, liver, thyroid, and kidney. There has long been a need for fluoride removal from potable water to make it safe for human use. From among several defluoridation technologies, adsorption is the technology most commonly used due to its cost-effectiveness, ease of operation, and simple physical process. In this paper, the adsorption capacities and fluoride removal efficiencies of different types of adsorbents are compiled from relevant published data available in the literature and represented graphically. The most promising adsorbents tested so far from each category of adsorbents are also highlighted. There is still a need to discover the actual feasibility of usage of adsorbents in the field on a commercial scale and to define the reusability of adsorbents to reduce cost and the waste produced from the adsorption process. The present paper reviews the currently available methods and emerging approaches for defluoridation of water. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Highly dealuminated Y zeolite as efficient adsorbent for the hydrophobic fraction from wastewater treatment plants effluents.

    Science.gov (United States)

    Navalon, Sergio; Alvaro, Mercedes; Garcia, Hermenegildo

    2009-07-15

    In this work we report that highly dealuminated zeolite Y is a hydrophobic material that is able to remove selectively fatty acids and hydrocarbon compounds from the effluent of an urban wastewater treatment plant (UWTP). This adsorbent capability of zeolite Y could lead to an improved quality of UWTP effluents. Typical domestic wastewaters contain detergents, soaps and surfactants that are only partially removed in conventional UWTP. In the present work using an effluent from a UWTP located at Ribarroja del Turia (Valencia, Spain) containing 10 ppm of total organic carbon, we have been able to retain by adsorption on the dealuminated Y zeolite up to 16 and 60% of the organic matter of the effluent at pH values 7.2 and 4, respectively. Characterization of the adsorbed organic matter by Fourier transformed infrared (FT-IR), (1)H NMR and GC-MS after derivatization has shown that the zeolite adsorbs selectively the hydrophobic compounds of the effluent.

  7. Asphaltene adsorption on quartz sand in the presence of pre-adsorbed water.

    Science.gov (United States)

    Gonzalez, Valeska; Taylor, Spencer E

    2016-10-15

    In the oil industry, asphaltenes are known for their tendency to aggregate in solution and to deposit on surfaces, with both properties being connected with operational problems associated with recovery, production and refining. Interactions involving asphaltenes and other crude oil components have been a major aspect of investigation in attempting to understand the full nature of these problems. Water is implicated in asphaltene behavior in solution, for example, where it has been found to delay the deposition of asphaltene aggregates. At interfaces, there is evidence that water-in-crude oil emulsion stability is enhanced through asphaltene-water interactions, and there have been a few reports that asphaltene adsorption on mineral surfaces is reduced in the presence of water. We consider the latter aspect, because the instances of reduced adsorption to date have not attempted to quantify the effect. Previous studies showed that vapor-phase adsorption of organic molecules is reduced in the presence of pre-adsorbed water and we were interested to determine whether the same is true for liquid-phase adsorption of asphaltenes. The surface of quartz sand was controlled by pre-adsorption of water from different relative humidity (RH) environments as the water adsorption isotherm is known from previous studies. These pre-conditioned sand samples were used as substrates for the adsorption from toluene solutions of n-heptane-precipitated asphaltenes (C7A) from an Athabasca oil sands bitumen. To supplement the adsorption behavior, atomic force microscopy (AFM) images were taken of the resultant sand grains at 0 and 80% RH, and low-field NMR was used to estimate the sand wettability. Asphaltene adsorption on sand is sensitive to surface-adsorbed water, with ∼4-fold reduction in adsorption when increasing the RH from 0 to 100%. This is in general agreement with previous vapor-phase adsorption of small organic molecules, and is therefore believed to be the first demonstration

  8. Removal of organic matter from dairy industry waste water using low-cost adsorbents

    Energy Technology Data Exchange (ETDEWEB)

    Rao, M.; Bhole, A.G. [College of Engineering, Badnera (India). Civil Engineering Department

    2002-07-01

    The present study envisages the use of cost-effective adsorbents such as fly ash, bagasse, wheat straw dust, sawdust, and coconut coir for the reduction of the TDS (total dissolved solids) from dairy industry effluent waste water. PAC (powdered activated carbon) was also used and the results were compared. Sorption data have been correlated with both the Langmuir and the Freundlich adsorption isotherm models. The Freundlich static isotherm model is found applicable to all the six adsorbents for removing TDS from the dairy waste water. The order of selectivity is PAC, bagasse, fly ash, sawdust, wheat straw, coconut coir for the removal of TDS at optimum conditions. 8 refs., 6 figs., 3 tabs.

  9. Water-insoluble sericin/β-cyclodextrin/PVA composite electrospun nanofibers as effective adsorbents towards methylene blue.

    Science.gov (United States)

    Zhao, Rui; Wang, Yong; Li, Xiang; Sun, Bolun; Jiang, Ziqiao; Wang, Ce

    2015-12-01

    A novel water-insoluble sericin/β-cyclodextrin/poly (vinyl alcohol) composite nanofiber adsorbent was prepared by electrospinning and followed by thermal crosslinking for removal of cationic dye methylene blue from aqueous solution. Fourier transform infrared spectroscopy and solubility experiments confirmed that sericin and β-cyclodextrin were incorporated into the nanofibers and the crosslinking reaction occurred successfully. Kinetics, isotherms and thermodynamics analysis were studied for adsorption of methylene blue. The adsorption process is better fitted with the pseudo-second-order model and Langmuir isotherm model. The maximum adsorption capacities are 187.97, 229.89, and 261.10mg/g at the temperatures 293, 313 and 333 K, respectively. Thermodynamic parameters showed that methylene blue adsorption was endothermic and spontaneous. In addition, the fiber membrane adsorbent could be easily separated from dye solution and showed high recyclable removal efficiency. All these results suggest that crosslinked sericin/β-cyclodextrin/poly(vinyl alcohol) composite nanofibers could be potential recyclable adsorbents in dye wastewater treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Nanotribological properties of water films adsorbing atop, and absorbing below, graphene layers supported by metal substrates

    Science.gov (United States)

    Liu, Zijian; Curtis, C. K.; Stine, R.; Sheehan, P.; Krim, J.

    The tribological properties of graphite, a common lubricant with known sensitivity to the presence of water, have been studied extensively at the macroscopic and microscopic scales. Although far less attention has been devoted to the tribological properties of graphene, it has been established that the tribological response to the presence of water is dissimilar from that of graphite. We report here a quartz crystal microbalance study of the nanotribological properties of water films adsorbed/absorbed on graphene layers prepared by either chemical decomposition on nickel(111) substrates or transfer of freestanding graphene layers to aluminum substrates. Sliding friction levels of the water films were also measured for metal surfaces in the absence of a graphene layer. We observe very high friction levels for water adsorbed atop graphene on Ni(111) and very low levels for water on aluminum. For the case of graphene/aluminum, the data indicate that the water is absorbing between the graphene layer and the aluminum. Dissipation levels moreover indicate the presence of an interstitial water increases sliding friction between the graphene and the aluminum substrate Work supported by NSF and NRL.

  11. Efficient arsenic(V) removal from water by ligand exchange fibrous adsorbent.

    Science.gov (United States)

    Awual, Md Rabiul; Shenashen, M A; Yaita, Tsuyoshi; Shiwaku, Hideaki; Jyo, Akinori

    2012-11-01

    This study is an efficient arsenic(V) removal from contaminated waters used as drinking water in adsorption process by zirconium(IV) loaded ligand exchange fibrous adsorbent. The bifunctional fibers contained both phosphonate and sulfonate groups. The bifunctional fiber was synthesised by graft polymerization of chloromethylstyrene onto polyethylene coated polypropylene fiber by means of electron irradiation graft polymerization technique and then desired phosphonate and sulfonate groups were introduced by Arbusov reaction followed by phosphorylation and sulfonation. Arsenic(V) adsorption was clarified in column methods with continuous flow operation in order to assess the arsenic(V) removal capacity in various conditions. The adsorption efficiency was evaluated in several parameters such as competing ions (chloride and sulfate), feed solution acidity, feed flow rate, feed concentration and kinetic performances at high feed flow rate of trace concentration arsenic(V). Arsenic(V) adsorption was not greatly changed when feed solutions pH at 3.0-7.0 and high breakthrough capacity was observed in strong acidic area below pH 2.2. Increasing the flow rate brings a decrease both breakthrough capacity and total adsorption. Trace level of arsenic(V) (0.015 mM) in presence of competing ions was also removed at high flow rate (750 h(-1)) with high removal efficiency. Therefore, the adsorbent is highly selective to arsenic(V) even in the presence of high concentration competing ions. The adsorbent is reversible and reusable in many cycles without any deterioration in its original performances. Therefore, Zr(IV) loaded ligand exchange adsorbent is to be an effective means to treat arsenic(V) contaminated water efficiently and able to safeguard the human health. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Reticular Chemistry in Action: A Hydrolytically Stable MOF Capturing Twice Its Weight in Adsorbed Water

    KAUST Repository

    Towsif Abtab, Sk Md

    2018-01-11

    Summary Hydrolytically stable adsorbents, with notable water uptake, are of prime importance and offer great potential for many water-adsorption-related applications. Nevertheless, deliberate construction of tunable porous solids with high porosity and high stability remains challenging. Here, we present the successful deployment of reticular chemistry to address this demand: we constructed Cr-soc-MOF-1, a chemically and hydrolytically stable chromium-based metal-organic framework (MOF) with underlying soc topology. Prominently, Cr-soc-MOF-1 offers the requisite thermal and chemical stability concomitant with unique adsorption properties, namely extraordinary high porosity (apparent surface area of 4,549 m2/g) affording a water vapor uptake of 1.95 g/g at 70% relative humidity. This exceptional water uptake is maintained over more than 100 adsorption-desorption cycles. Markedly, the adsorbed water can be fully desorbed by just the simple reduction of the relative humidity at 25°C. Cr-soc-MOF-1 offers great potential for use in applications pertaining to water vapor control in enclosed and confined spaces and dehumidification.

  13. Zinc peroxide nanomaterial as an adsorbent for removal of Congo red dye from waste water.

    Science.gov (United States)

    Chawla, Sneha; Uppal, Himani; Yadav, Mohit; Bahadur, Nupur; Singh, Nahar

    2017-01-01

    In the past decade, various natural byproducts, advanced metal oxide composites and photocatalysts have been reported for removal of dyes from water. Although these materials are useful for select applications, they have some limitations such as use at fixed temperature, ultra violet (UV) light and the need for sophisticated experimental set up. These materials can remove dyes up to a certain extent but require long time. To overcome these limitations, a promising adsorbent zinc peroxide (ZnO 2 ) nanomaterial has been developed for the removal of Congo red (CR) dye from contaminated water. ZnO 2 is highly efficient even in the absence of sunlight to remove CR from contaminated water upto the permissible limits set by the World Health Organization (WHO) and the United States- Environmental Protection Agency (US-EPA). The adsorbent has a specific property to adjust the pH of the test solution within 6.5-7.5 range irrespective of acidic or basic nature of water. The adsorption capacity of the material for CR dye was 208mgg -1 within 10min at 2-10pH range. The proposed material could be useful for the industries involved in water purification. The removal of CR has been confirmed by spectroscopic and microscopic techniques. The adsorption data followed a second order kinetics and Freundlich isotherm. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Sulfur dioxide adsorption and photooxidation on isotopically-labeled titanium dioxide nanoparticle surfaces: roles of surface hydroxyl groups and adsorbed water in the formation and stability of adsorbed sulfite and sulfate.

    Science.gov (United States)

    Nanayakkara, Charith E; Pettibone, John; Grassian, Vicki H

    2012-05-21

    Transmission FTIR spectroscopy and X-ray photoelectron spectroscopy (XPS) are used to probe the details of sulfur dioxide adsorption and photooxidation on titanium dioxide nanoparticle surfaces. Adsorption sites, surface speciation and photooxidation chemistry have been determined from analysis of FTIR spectra in conjunction with isotope labeling experiments. These data show that surface hydroxyl groups are involved in the adsorption of sulfur dioxide, and in particularly, sulfur dioxide reacts with either one surface O-H group to yield adsorbed bisulfite or two surface O-H groups to yield adsorbed sulfite and water. Using (16)O-H, (16)O-D and (18)O-H labeled surface O-H groups, additional insights into the adsorption mechanism as well as shifts in the vibrational modes of adsorbed sulfite have been determined. Upon irradiation, adsorbed sulfite/bisulfite converts to adsorbed sulfate. The relative stability of adsorbed sulfite to adsorbed sulfate on TiO2 nanoparticle surfaces was also examined in the presence of increasing relative humidity (RH). It is shown here that adsorbed water can more easily displace sulfite compared to sulfate by forming a stable sulfur dioxide water complex in the presence of adsorbed water. These differences in the RH-dependent stability of adsorbed species that form as a result of surface heterogeneous reactions on oxide particles surfaces has important implications in the heterogeneous chemistry of mineral dust aerosol in the atmosphere.

  15. The role of adsorbed water on the friction of a layer of submicron particles

    Science.gov (United States)

    Sammis, Charles G.; Lockner, David A.; Reches, Ze’ev

    2011-01-01

    Anomalously low values of friction observed in layers of submicron particles deformed in simple shear at high slip velocities are explained as the consequence of a one nanometer thick layer of water adsorbed on the particles. The observed transition from normal friction with an apparent coefficient near μ = 0.6 at low slip speeds to a coefficient near μ = 0.3 at higher slip speeds is attributed to competition between the time required to extrude the water layer from between neighboring particles in a force chain and the average lifetime of the chain. At low slip speeds the time required for extrusion is less than the average lifetime of a chain so the particles make contact and lock. As slip speed increases, the average lifetime of a chain decreases until it is less than the extrusion time and the particles in a force chain never come into direct contact. If the adsorbed water layer enables the otherwise rough particles to rotate, the coefficient of friction will drop to μ = 0.3, appropriate for rotating spheres. At the highest slip speeds particle temperatures rise above 100°C, the water layer vaporizes, the particles contact and lock, and the coefficient of friction rises to μ = 0.6. The observed onset of weakening at slip speeds near 0.001 m/s is consistent with the measured viscosity of a 1 nm thick layer of adsorbed water, with a minimum particle radius of approximately 20 nm, and with reasonable assumptions about the distribution of force chains guided by experimental observation. The reduction of friction and the range of velocities over which it occurs decrease with increasing normal stress, as predicted by the model. Moreover, the analysis predicts that this high-speed weakening mechanism should operate only for particles with radii smaller than approximately 1 μm. For larger particles the slip speed required for weakening is so large that frictional heating will evaporate the adsorbed water and weakening will not occur.

  16. Alternative treatments to improve the potential of rice husk as adsorbent for methylene blue.

    Science.gov (United States)

    Franco, Dison S P; Tanabe, Eduardo H; Bertuol, Daniel A; Dos Reis, Glaydson S; Lima, Éder C; Dotto, Guilherme L

    2017-01-01

    Alternative treatments, such as, NaOH, ultrasound assisted (UA) and supercritical CO2 (SCO2), were performed to improve the potential of rice husk as adsorbent to remove methylene blue (MB) from aqueous media. All the treatments improved the surface characteristics of rice husk, exposing its organic fraction and/or providing more adsorption sites. The Langmuir and Hill models were able to explain the MB adsorption for all adsorbents in all studied temperatures. The experimental and modeled parameters demonstrated that the MB adsorption was favored by the temperature increase and by the use of NaOH-rice husk. The maximum adsorption capacities for the MB solutions (ranging from 10 to 100 mg L-1), estimated from the Langmuir model at 328 K, were in the following order: NaOH rice-husk (65.0 mg g-1) > UA-rice husk (58.7 mg g-1) > SCO2-rice husk (56.4 mg g-1) > raw rice husk (52.2 mg g-1). The adsorption was a spontaneous, favorable and endothermic process. In general, this work demonstrated that NaOH, UA and SCO2 treatments are alternatives to improve the potential of rice husk as adsorbent.

  17. A review of the use of red mud as adsorbent for the removal of toxic pollutants from water and wastewater.

    Science.gov (United States)

    Bhatnagar, Amit; Vilar, Vítor J P; Botelho, Cidália M S; Boaventura, Rui A R

    2011-01-01

    Red mud (an aluminium industry waste) has received wide attention as an effective adsorbent for water pollution control, showing significant adsorption potential for the removal of various aquatic pollutants. In this review, an extensive list of red-mud-based adsorbents has been compiled and their adsorption capacities (maximum uptake value of the adsorbent for the pollutant or adsorbate being removed) for various aquatic pollutants (metal ions, dyes, phenolic compounds, inorganic anions) are presented. The review provides a summary of recent information obtained using batch studies and deals with the adsorption mechanisms involved. It is evident from the literature survey that red mud has been found to be efficient for the removal of various aquatic pollutants, especially arsenic and phosphate. However, there is still a need to investigate the practical utility of these adsorbents on a commercial scale.

  18. Dynamical property of water droplets of different sizes adsorbed onto a poly(methyl methacrylate) surface.

    Science.gov (United States)

    Lee, Wen-Jay; Ju, Shin-Pon

    2010-01-05

    A molecular dynamics approach has been employed to study the dynamical behavior of a water droplet adsorbed on a poly(methyl methacrylate) (PMMA) surface. Several sizes of water droplets are considered in order to understand the size influence of the droplet on the dynamical properties of water molecules on the PMMA substrate. The local density profile of water molecules in the droplet upon impact with the PMMA surface is calculated, and the result shows an increase in water penetration with a decrease in the size of the droplet. By examining the velocity field, the regular motion of the water droplet is found both during the equilibrium process and after the droplet reaches the equilibrium state. The dynamical behavior of water molecule is studied by the velocity autocorrelation function (VACF) in different regions for different sizes of water droplets. The result shows that VACFs in different regions are significantly influenced for the droplet with 500 water molecules than for that with 2000 water molecules. Calculations in different regions are made for the vibrational spectrum of the oxygen atom, as well as for hydrogen bond dynamics, the lifetime, and the relaxation time of the hydrogen bond. The changes in the hydrogen bond dynamics are consistent with the change in the distribution of the hydrogen bond angle. We conclude that the dynamical properties of the water molecule are significantly affected by the region relative to the surface but only weakly influenced by the size of the droplet.

  19. Use of Drinking Water Sludge as Adsorbent for H2S Gas Removal from Biogas

    Directory of Open Access Journals (Sweden)

    Sucheela Polruang

    2017-01-01

    Full Text Available This paper reports the results of a research project, which attempts to produce a low-cost adsorbent material from waste (drinking water sludge. The main objective of this work is to study the characteristics of drinking water sludge for its adsorptive properties including morphology, surface area, porosity and chemical composition. The effect of activation conditions on H2S gas adsorption efficiency of drinking water sludge was experimented. In this study, raw drinking water sludge was divided into 3 groups. In the first group, drinking water sludge was only oven dried at 105°C. For the other 2 groups, drinking water sludge was soaked in 2.5 M NaOH solution. After soaking, the sludge was divided into 2 groups (group 2 and 3. The second group was washed with distilled water until pH 7; while the third group was not. Biogas from a swine farm was used with an initial H2S gas concentration in the range of 2,000 - 4,000 ppm. The material analysis showed that more surface area and total volume of sludge can be obtained after activated with NaOH. From the adsorption experiments, it was found that the highest adsorption capacity (qe of 87.94 mg H2S/g adsorptive material can be achieved by using sludge from the third group. Moreover, by adding of 20 wt% iron filing into sludge of the third group the adsorption capacity increased to 105.22 mg H2S/g adsorptive material. Drinking water sludge can be considered as a high potential energy saving and low cost adsorbent for removal of H2S.

  20. The potential use of rainwater as alternative source of drinking water by using laterite soil as natural adsorbent

    Science.gov (United States)

    Omar, Khairunnisa Fakhriah Mohd; Palaniandy, Puganeshwary; Adlan, Mohd Nordin; Aziz, Hamidi Abdul; Subramaniam, Ambarasi

    2017-10-01

    Generally, the rainwater has low concentration of pollutants, whereby it is applicable for domestic water supply. Due to the low concentration of pollutants, further treatment such as adsorption is necessary to treat the harvested rainwater as an alternative source of drinking water supply. Therefore, this research has been carried out to determine the quality of rainwater from different types of locations, which are; rural residential area, urban residential area, agricultural area, industrial area, and open surface. The rainwater sampling was carried out from September 2014 to December 2015. The parameters that have been analysed during the sampling process are chemical oxygen demand (COD), turbidity, heavy metals, and Escherichia coli (E.coli). The sampling results show that the rainwater provides low concentration of contaminants. Thus, it has high potential to be used as alternative source of potable and non potable water supply with a suitable treatment. Due to that, an experimental work contained of 86 of designated experiments for a batch study has been carried out to determine the performance of laterite soil as an adsorbent to remove pollutants that present in the rainwater (i.e. zinc, manganese, and E.coli). The operating factors involved in the experimental works are pH, mass of adsorbents, contact time, initial concentration of zinc, manganese, and E.coli. In this study, the experimental data of the batch study was analysed by developing regression model equation and analysis of variance. Perturbation plots were analysed to determine the effectiveness of the operating factors by developing response surface model, resulting that the high removals of zinc, manganese, and E.coli are 95.8%, 94.05% and 100%, respectively. Overall, this research works found out that the rainwater has a good quality as alternative source of drinking water by providing a suitable treatment. The application of laterite soil as natural adsorbent shows that it has potential to be

  1. Mesoporous hexagonal and cubic aluminosilica adsorbents for toxic nitroanilines from water.

    Science.gov (United States)

    El-Safty, Sherif A; Ismael, M; Shahat, A; Shenashen, M A

    2013-06-01

    In the present study, ordered mesocage hexagonal P6mm and cubic Pm3n aluminosilica nanoadsorbents with monolith-like morphology and micro-, meso-, and macro-pores were fabricated using a simple, reproducible, direct synthesis. Our results suggest that the aluminosilica nanoadsorbents attained the ordering and uniform hexagonal and cubic pores even at the high Si/Al ratio of 4. The acidity of nanoadsorbents significantly based on the amount of aluminum species in the walls of the silica pore framework. Aluminosilica nanoadsorbents were used as a removal of environmentally toxic aromatic amines, namely p-nitroaniline (p-NA), from wastewater. The loading amount of Bronsted acid sites, mesostructural geometries, and multi-directional pores (3D) of the aluminosilica adsorbents played a key factor in the enhancement of the coverage adsorbent surfaces and intraparticle diffusion of adsorbate molecules onto the network surfaces and into the pore architectures of monoliths. Significantly, we developed theoretical models to explain the 3D microscopic geometry and the pore orientation of aluminosilica monoliths. A key component of the nanoadsorbents is the ability to create revisable p-NA adsorption systems with multiple reuse cycles. However, simple treatment using an acidic aqueous solution was found to remove effectively the p-NA and to form "p-NA-free" pore surfaces without any mesostructural damage.

  2. Forsterite Carbonation in Wet-scCO2: Dependence on Adsorbed Water Concentration

    Science.gov (United States)

    Loring, J.; Benezeth, P.; Qafoku, O.; Thompson, C.; Schaef, T.; Bonneville, A.; McGrail, P.; Felmy, A.; Rosso, K.

    2013-12-01

    Capturing and storing CO2 in basaltic formations is one of the most promising options for mitigating atmospheric CO2 emissions resulting from the burning of fossil fuels. These geologic reservoirs have high reactive potential for CO2-mineral trapping due to an abundance of divalent-cation containing silicates, such as forsterite (Mg2SiO4). Recent studies have shown that carbonation of these silicates under wet scCO2 conditions, e. g. encountered near a CO2 injection well, proceeds along a different pathway and is more effective than in CO2-saturated aqueous fluids. The presence of an adsorbed water film on the forsterite surface seems to be key to reactivity towards carbonation. In this study, we employed in situ high pressure IR spectroscopy to investigate the dependence of adsorbed water film thickness on forsterite carbonation chemistry. Post reaction ex situ SEM, TEM, TGA, XRD, and NMR measurements will also be discussed. Several IR titrations were performed of forsterite with water at 50 °C and 90 bar scCO2. Aliquots of water were titrated at 4-hour reaction-time increments. Once a desired total water concentration was reached, data were collected for about another 30 hours. One titration involved 10 additions, which corresponds to 6.8 monolayers of adsorbed water. Clearly, a carbonate was precipitating, and its spectral signature matched magnesite. Another titration involved 8 aliquots, or up to 4.4 monolayers of water. The integrated absorbance under the CO stretching bands of carbonate as a function of time after reaching 4.4 monolayers showed an increase and then a plateau. We are currently unsure of the identity of the carbonate that precipitated, but it could be an amorphous anhydrous phase or magnesite crystals with dimensions of only several nanometers. A third titration only involved 3 additions, or up to 1.6 monolayers of water. The integrated absorbance under the CO stretching bands of carbonate as a function of time after reaching 1.6 monolayers

  3. Removal of trace arsenic(V) and phosphate from water by a highly selective ligand exchange adsorbent.

    Science.gov (United States)

    Awual, Md Rabiul; El-Safty, Sherif A; Jyo, Akinori

    2011-01-01

    A highly selective ligand exchange type adsorbent was developed for the removal of trace arsenic(V) (As(V)) and phosphate from water. This adsorbent was prepared by loading zirconium(IV) on monophosphonic acid resin. This adsorbent was able to remove toxic anions efficiently at wide pH ranges. However, low pH was preferable for maximum breakthrough capacity in an adsorption operation. The effect of a large amount of competing anions such as chloride, bicarbonate, and sulfate on the adsorption systems of As(V) and phosphate anions was investigated. The experimental findings revealed that the As(V) and phosphate uptakes were not affected by these competing anions despite the enhancement of the breakthrough points and total adsorption. Phosphate anion was slightly preferable than As(V) in their competitive adsorption by the adsorbent. The adsorbed As(V) and phosphate on the Zr(IV)-loaded resin were quantitatively eluted with 0.1 mol/L sodium hydroxide solution, and the adsorbent was regenerated by 0.5 mol/L sulfuric acid. During several cycles of adsorption-elution-regeneration operations, no Zr(IV) was detected in the column effluents. Therefore, the Zr(IV)-loaded monophosphonic acid resin is an effective ligand exchange adsorbent for removing trace concentrations of As(V) and phosphate from water.

  4. Mechanical properties of hexadecane-water interfaces with adsorbed hydrophobic bacteria

    Science.gov (United States)

    Kang, Zhewen

    Certain strains of hydrophobic bacteria are known to play critical roles in petroleum-related applications. The aim of this study was to investigate how hydrophobic bacteria in their stationary phase could adsorb onto the hexadecane-water interface and alter its mechanical properties. The two strains of bacteria used in forming the interfacial films were Acinetobacter venetianus RAG-1 (a Gram-negative bacterium) and Rhodococcus erythropolis 20S-E1-c (Gram-positive). Experiments at two different length scales (millimetre and micrometre) were conducted and the results were compared. In addition, a simple flow experiment was designed in a constricted channel and the results were related to the intrinsic mechanical properties of bacteria-adsorbed films. On the millimetre scale, using the pendant drop technique, the film interfacial tension was monitored as the surface area was made to undergo changes. Under static conditions, both types of bacteria showed no significant effect on the interfacial tension. When subjected to transient excitations, the two bacterial films exhibited qualitatively similar, yet quantitative distinct rheological properties (including film elasticities and relaxation times). Under continuous reduction of surface area, the RAG-1 system showed a "paper-like" interface, while the interface of the 20S-E1-c system was "soap film-like." These macroscopic observations could be explained by the surface ultrastructures of the two cell strains. On the micrometre scale, using the micropipette technique, colloidal stability of the bacteria-coated oil droplets was examined through direct-contact experiments. Both types of bacteria were seen to function as effective stabilizers. In addition, the adsorbed bacteria also interacted with one another at the interface, giving rise to higher order 2-D rheological properties. A technique of directly probing the mechanical properties of the emulsion drop surfaces revealed that (a) the films behaved as purely elastic

  5. Ceria modified activated carbon: an efficient arsenic removal adsorbent for drinking water purification

    Science.gov (United States)

    Sawana, Radha; Somasundar, Yogesh; Iyer, Venkatesh Shankar; Baruwati, Babita

    2017-06-01

    Ceria (CeO2) coated powdered activated carbon was synthesized by a single step chemical process and demonstrated to be a highly efficient adsorbent for the removal of both As(III) and As(V) from water without any pre-oxidation process. The formation of CeO2 on the surface of powdered activated carbon was confirmed by X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy. The percentage of Ce in the adsorbent was confirmed to be 3.5 % by ICP-OES. The maximum removal capacity for As(III) and As(V) was found to be 10.3 and 12.2 mg/g, respectively. These values are comparable to most of the commercially available adsorbents. 80 % of the removal process was completed within 15 min of contact time in a batch process. More than 95 % removal of both As(III) and As(V) was achieved within an hour. The efficiency of removal was not affected by change in pH (5-9), salinity, hardness, organic (1-4 ppm of humic acid) and inorganic anions (sulphate, nitrate, chloride, bicarbonate and fluoride) excluding phosphate. Presence of 100 ppm phosphate reduced the removal significantly from 90 to 18 %. The equilibrium adsorption pattern of both As(III) and As(V) fitted well with the Freundlich model with R 2 values 0.99 and 0.97, respectively. The material shows reusability greater than three times in a batch process (arsenic concentration reduced below 10 ppb from 330 ppb) and a life of at least 100 L in a column study with 80 g material when tested under natural hard water (TDS 1000 ppm, pH 7.8, hardness 600 ppm as CaCO3) spiked with 330 ppb of arsenic.

  6. Impacts of surface adsorbed catechol on tropospheric aerosol surrogates: heterogeneous ozonolysis and its effects on water uptake.

    Science.gov (United States)

    Woodill, Laurie A; O'Neill, Erinn M; Hinrichs, Ryan Z

    2013-07-11

    Surface adsorbed organics are ubiquitous components of inorganic tropospheric aerosols and have the potential to alter aerosol chemical and physical properties. To assess the impact of adsorbed organics on water uptake by inorganic substrates, we used diffuse reflectance infrared spectroscopy to compared water adsorption isotherms for uncoated NaCl and α-Al2O3 samples, samples containing a monolayer of adsorbed catechol, and adsorbed catechol samples following ozonolysis. Adsorption of gaseous catechol on to the inorganic substrates produced vibrational features indicating physisorption on NaCl and displacement of surface hydroxyl groups forming binuclear bidentate catecholate on α-Al2O3, with surface concentrations of 2-3 × 10(18) molecules m(-2). Subsequent heterogeneous ozonolysis produced muconic acid at a rate 4-5 times faster on NaCl compared to α-Al2O3, with predicted atmospheric lifetimes of 4.3 and 18 h, respectively, assuming a tropospheric ozone concentration of 40 ppb. Water adsorption isotherms for all NaCl samples were indistinguishable within experimental uncertainty, indicating that these organic monolayers had negligible impact on coadsorbed water surface concentrations for these systems. α-Al2O3-catechol samples exhibited dramatically less water uptake compared to uncoated α-Al2O3, while oxidation of surface adsorbed catechol had no effect on the extent of water uptake. For both substrates, adsorbed organics increased the relative abundance of "ice-like" versus "liquid-like" water, with the effect larger for catechol than oxidized ozonolysis products. These results highlight the importance of aerosol substrate in understanding the heterogeneous ozonolysis of adsorbed polyphenols and suggest such coatings may impair ice nucleation by aluminosilicate mineral aerosol.

  7. Food-processes wastewaters treatment using food solid-waste materials as adsorbents or absorbents

    Science.gov (United States)

    Rapti, Ilaira; Georgopoulos, Stavros; Antonopoulou, Maria; Konstantinou, Ioannis; Papadaki, Maria

    2016-04-01

    The wastewaters generated by olive-mills during the production of olive oil, wastewaters from a dairy and a cow-farm unit and wastewaters from a small food factory have been treated by means of selected materials, either by-products of the same units, or other solid waste, as absorbents or adsorbents in order to identify the capacity of those materials to remove organic load and toxicity from the aforementioned wastewaters. The potential of both the materials used as absorbents as well as the treated wastewaters to be further used either as fertilizers or for agricultural irrigation purposes are examined. Dry olive leaves, sheep wool, rice husks, etc. were used either in a fixed-bed or in a stirred batch arrangemen,t employing different initial concentrations of the aforementioned wastewaters. The efficiency of removal was assessed using scpectrophotometric methods and allium test phytotoxicity measurements. In this presentation the response of each material employed is shown as a function of absorbent/adsorbent quantity and kind, treatment time and wastewater kind and initial organic load. Preliminary results on the potential uses of the adsorbents/absorbents and the treated wastewaters are also shown. Keywords: Olive-mill wastewaters, dairy farm wastewaters, olive leaves, zeolite, sheep wool

  8. Alternative disinfectant water treatments

    Science.gov (United States)

    Alternative disinfestant water treatments are disinfestants not as commonly used by the horticultural industry. Chlorine products that produce hypochlorous acid are the main disinfestants used for treating irrigation water. Chlorine dioxide will be the primary disinfestant discussed as an alternativ...

  9. Polyethyleneimine-carbon nanotube polymeric nanocomposite adsorbents for the removal of Cr6+ from water

    Science.gov (United States)

    Sambaza, Shepherd S.; Masheane, Monaheng L.; Malinga, Soraya P.; Nxumalo, Edward N.; Mhlanga, Sabelo D.

    2017-08-01

    This work reports on the synthesis of multi-walled carbon nanotubes (MWCNTs) and their use in branched polyethyleneimine-multiwalled carbon nanotube (PEI-MWCNT) polymeric nanocomposite adsorbents for the removal of Cr6+ from contaminated water. The nanostructured materials were characterized using TEM, Raman, FTIR, BET surface area and zeta potential measurements. TEM confirmed the average diameter of the MWCNTs to be 25 nm. The point of zero-charge of PEI was at pH 8 and that of PEI-MWCNTs was at pH 7.7. FTIR analysis confirmed the formation of a new bond (-Cdbnd O at 1716 cm-1) between the functional groups on the MWCNTs and PEI. Batch adsorption and kinetic studies showed that the PEI-MWCNT nanocomposite materials were more efficient in the removal of Cr6+ solution from water samples. The optimum conditions for adsorption were pH ≤ 4, contact time of 60 min. When the PEI-MWCNT dosage was increased the adsorption capacity increased. The kinetic adsorption data obtained for Cr6+ solution followed pseudo-second order model. The adsorption of Cr6+ solution reached equilibrium within 60 min of contact time with a removal of 99%. The adsorbents were effective even after 5 cycles of use.

  10. Removal of Cu (II and Zn (II from water with natural adsorbents from cassava agroindustry residues

    Directory of Open Access Journals (Sweden)

    Daniel Schwantes

    2015-07-01

    Full Text Available Current study employs solid residues from the processing industry of the cassava (Manihot esculenta Crantz (bark, bagasse and bark + bagasse as natural adsorbents for the removal of metal ions Cu(II and Zn(II from contaminated water. The first stage comprised surface morphological characterization (SEM, determination of functional groups (IR, point of zero charge and the composition of naturally existent minerals in the biomass. Further, tests were carried out to evaluate the sorption process by kinetic, equilibrium and thermodynamic studies. The adsorbents showed a surface with favorable adsorption characteristics, with adsorption sites possibly derived from lignin, cellulose and hemicellulose. The dynamic equilibrium time for adsorption was 60 min. Results followed pseudo-second-order, Langmuir and Dubinin-Radushkevich models, suggesting a chemisorption monolayer. The thermodynamic parameters suggested that the biosorption process of Cu and Zn was endothermic, spontaneous or independent according to conditions. Results showed that the studied materials were potential biosorbents in the decontamination of water contaminated by Cu(II and Zn(II. Thus, the above practice complements the final stages of the cassava production chain of cassava, with a new disposal of solid residues from the cassava agroindustry activity.

  11. Adsorption Characteristics of Different Adsorbents and Iron(III Salt for Removing As(V from Water

    Directory of Open Access Journals (Sweden)

    Josip Ćurko

    2016-01-01

    Full Text Available The aim of this study is to determine the adsorption performance of three types of adsorbents for removal of As(V from water: Bayoxide® E33 (granular iron(III oxide, Titansorb® (granular titanium oxide and a suspension of precipitated iron(III hydroxide. Results of As(V adsorption stoichiometry of two commercial adsorbents and precipitated iron(III hydroxide in tap and demineralized water were fitted to Freundlich and Langmuir adsorption isotherm equations, from which adsorption constants and adsorption capacity were calculated. The separation factor RL for the three adsorbents ranged from 0.04 to 0.61, indicating effective adsorption. Precipitated iron(III hydroxide had the greatest, while Titansorb had the lowest capacity to adsorb As(V. Comparison of adsorption from tap or demineralized water showed that Bayoxide and precipitated iron(III hydroxide had higher adsorption capacity in demineralized water, whereas Titansorb showed a slightly higher capacity in tap water. These results provide mechanistic insights into how commonly used adsorbents remove As(V from water.

  12. Removal of Lead from Water Using Calcium Alginate Beads Doped with Hydrazine Sulphate-Activated Red Mud as Adsorbent

    Directory of Open Access Journals (Sweden)

    A. Naga Babu

    2017-01-01

    Full Text Available Calcium alginate beads doped with hydrazine sulphate-treated red mud are investigated as adsorbent for extracting lead ions from water using batch methods of extraction. Different extraction conditions are optimised for maximum lead extraction. Substantial amount of lead is removed, and the adsorption ability is found to be 138.6 mg/g. Surface characterization using FTIR, EDX, and FESEM confirms that lead is “onto” the surface of the adsorbent. Thermodynamic parameters, adsorption isotherms, and kinetics of adsorption are analysed. Adsorption is “physisorption” in nature and spontaneous. The adsorbent developed can be regenerated using 0.1 M HCl. Thus regenerated adsorbent can be used as the adsorbent for further removal of lead at least 10 times, and this enables the complete removal of lead from water by repetitive use of the regenerated adsorbent. The beads facilitate the easy filtration. The methodology developed is successfully applied for removing lead from industrial waste waters.

  13. Novel Anionic Clay Adsorbents for Boiler-Blow-Down Waters Reclaim and Reuse

    Energy Technology Data Exchange (ETDEWEB)

    Muhammad Sahimi; Theodore Tsotsis

    2010-01-08

    Arsenic (As) and Selenium (Se) are found in water in the form of oxyanions. Relatively high concentrations of As and Se have been reported both in power plant discharges, as well as, in fresh water supplies. The International Agency for Research on Cancer currently classifies As as a group 1 chemical, that is considered to be carcinogenic to humans. In Phase I of this project we studied the adsorption of As and Se by uncalcined and calcined layered double hydroxide (LDH). The focus of the present work is a systematic study of the adsorption of As and Se by conditioned LDH adsorbents. Conditioning the adsorbent significantly reduced the Mg and Al dissolution observed with uncalcined and calcined LDH. The adsorption rates and isotherms have been investigated in batch experiments using particles of four different particle size ranges. As(V) adsorption is shown to follow a Sips-type adsorption isotherm. The As(V) adsorption rate on conditioned LDH increases with decreasing adsorbent particle size; the adsorption capacity, on the other hand, is independent of the particle size. A homogeneous surface diffusion model (HSDM) and a bi-disperse pore model (BPM) - the latter viewing the LDH particles as assemblages of microparticles and taking into account bulk diffusion in the intraparticle pore space, and surface diffusion within the microparticles themselves - were used to fit the experimental kinetic data. The HSDM estimated diffusivity values dependent on the particle size, whereas the BPM predicted an intracrystalline diffusivity, which is fairly invariant with particle size. The removal of As(V) on conditioned LDH adsorbents was also investigated in flow columns, where the impact of important solution and operational parameters such as influent As concentration, pH, sorbent particle size and flow rate were studied. An early breakthrough and saturation was observed at higher flow rates and at higher influent concentrations, whereas a decrease in the sorbent particle

  14. Removal of atrazine from water by low cost adsorbents derived from agricultural and industrial wastes.

    Science.gov (United States)

    Sharma, Rajendra Kumar; Kumar, Anoop; Joseph, P E

    2008-05-01

    In the present study six adsorbents viz. wood charcoal, fly ash, coconut charcoal, saw dust, coconut fiber and baggasse charcoal were studied for their capacity to remove atrazine from water. The removal efficiency of different adsorbents varied from 76.5% to 97.7% at 0.05 ppm concentration and 78.5% to 95.5% at 0.1 ppm concentration of atrazine solution, which was less than removal efficiency of activated charcoal reported as 98% for atrazine (Adams and Watson, J Environ Eng ASCE 39:327-330, 1996). Wood charcoal was a cheap (Rs 15 kg(-1)) and easily available material in house holds. Since wood charcoal was granular in nature, it could be used for the removal of atrazine from water to the extent of 95.5%-97.7%. Fly ash is a waste product of thermal plant containing 40%-50% silica, 20%-35% alumina, 12%-30% carbon and unburnt minerals having a high pH of 9-10. It is very cheap and abundant material and has comparatively good adsorption capacity. It was found that fly ash effectively removed about 84.1%-88.5% atrazine from water at 0.05 and 0.1 ppm levels. Coconut shell is also waste product. Therefore, both are inexpensive. The removal efficiency of atrazine from water was 92.4%-95.2% by coconut shell charcoal and 85.9%-86.3% by coconut fiber. Sawdust is generally used as domestic fuel and found everywhere. It is also very cheap (Re. 1 kg(-1)). Baggasse charcoal is a waste product of sugar mill and abundant material. Its cost is due to transport expense, which depends upon distance from the sugar mill. The removal efficiency of sawdust and baggasse charcoal was found 78.5-80.5 and 76.5-84.6, respectively. The efficacy of chemically treated adsorbents for the removal of atrazine from water is in the order: wood charcoal > coconut shell charcoal > fly ash > coconut fiber charcoal > baggasse charcoal > sawdust.

  15. Adsorption of phenol and its derivatives from water using synthetic resins and low-cost natural adsorbents: A review

    Energy Technology Data Exchange (ETDEWEB)

    Lin, S.H.; Juang, R.S. [Yuan Ze University, Chungli (Taiwan). Dept. of Chemical Engineering and Material Science

    2009-03-15

    In this article, the technical feasibility of the use of activated carbon, synthetic resins, and various low-cost natural adsorbents for the removal of phenol and its derivatives from contaminated water has been reviewed. Instead of using commercial activated carbon and synthetic resins, researchers have worked on inexpensive materials such as coal fly ash, sludge, biomass, zeolites, and other adsorbents, which have high adsorption capacity and are locally available. The comparison of their removal performance with that of activated carbon and synthetic resins is presented in this study. From our survey of about 100 papers, low-cost adsorbents have demonstrated outstanding removal capabilities for phenol and its derivatives compared to activated carbons. Adsorbents that stand out for high adsorption capacities are coal-reject, residual coal treated with H{sub 3}PO{sub 4}, dried activated sludge, red mud, and cetyl-trimethylammonium bromide-modified montmorillonite. Of these synthetic resins, HiSiv 1000 and IRA-420 display high adsorption capacity of phenol and XAD-4 has good adsorption capability for 2-nitrophenol. These polymeric adsorbents are suitable for industrial effluents containing phenol and its derivatives as mentioned previously. It should be noted that the adsorption capacities of the adsorbents presented here vary significantly depending on the characteristics of the individual adsorbent, the extent of chemical modifications, and the concentrations of solutes.

  16. Nano-adsorbents for the removal of metallic pollutants from water and wastewater.

    Science.gov (United States)

    Sharma, Y C; Srivastava, V; Singh, V K; Kaul, S N; Weng, C H

    2009-05-01

    Of the variety of adsorbents available for the removal of heavy and toxic metals, activated carbon has been the most popular. A number of minerals, clays and waste materials have been regularly used for the removal of metallic pollutants from water and industrial effluents. Recently there has been emphasis on the application of nanoparticles and nanostructured materials as efficient and viable alternatives to activated carbon. Carbon nanotubes also have been proved effective alternatives for the removal of metallic pollutants from aqueous solutions. Because of their importance from an environmental viewpoint, special emphasis has been given to the removal of the metals Cr, Cd, Hg, Zn, As, and Cu. Separation of the used nanoparticles from aqueous solutions and the health aspects of the separated nanoparticles have also been discussed. A significant number of the latest articles have been critically scanned for the present review to give a vivid picture of these exotic materials for water remediation.

  17. A method for preparing ferric activated carbon composites adsorbents to remove arsenic from drinking water.

    Science.gov (United States)

    Zhang, Qiao Li; Lin, Y C; Chen, X; Gao, Nai Yun

    2007-09-30

    Iron oxide/activated carbon (FeO/AC) composite adsorbent material, which was used to modify the coal-based activated carbon (AC) 12 x 40, was prepared by the special ferric oxide microcrystal in this study. This composite can be used as the adsorbent to remove arsenic from drinking water, and Langmuir isotherm adsorption equation well describes the experimental adsorption isotherms. Then, the arsenic desorption can subsequently be separated from the medium by using a 1% aqueous NaOH solution. The apparent characters and physical chemistry performances of FeO/AC composite were investigated by X-ray diffraction (XRD), nitrogen adsorption, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Batch and column adsorption experiments were carried out to investigate and compare the arsenic removal capability of the prepared FeO/AC composite material and virgin activated carbon. It can be concluded that: (1) the main phase present in this composite are magnetite (Fe(3)O(4)), maghemite (gamma-Fe(2)O(3)), hematite (alpha-Fe(2)O(3)) and goethite (alpha-FeO(OH)); (2) the presence of iron oxides did not significantly affect the surface area or the pore structure of the activated carbon; (3) the comparisons between the adsorption isotherms of arsenic from aqueous solution onto the composite and virgin activated carbon showed that the FeO/AC composite behave an excellent capacity of adsorption arsenic than the virgin activated carbon; (4) column adsorption experiments with FeO/AC composite adsorbent showed that the arsenic could be removed to below 0.01 mg/L within 1250 mL empty bed volume when influent concentration was 0.5mg/L.

  18. Molecular association of adsorbed water with lignocellulosic materials examined by micro-FTIR spectroscopy.

    Science.gov (United States)

    Guo, Xin; Qing, Yan; Wu, Yiqiang; Wu, Qinglin

    2016-02-01

    For lignocellulosic materials, water adsorption is extremely important for its product performance. For gaining a deeper understanding of moisture adsorption mechanisms, the molecular interactions between adsorbed water and a typical lignocellulosic material (i.e., wood) were studied using in-situ microscopic Fourier transform infrared (micro-FTIR) spectroscopy and a specially designed sample cell. The spectral shifts of 1733 cm(-1), 1604 cm(-1) and 1236 cm(-1) and different spectra between the moist and dry spectra indicated that carbonyl CO and CO groups preferred to combine with water molecules to form hydrogen bonds. From component band analysis of the spectral range of 2900-3700 cm(-1), three peaks at 3178 cm(-1), 3514 cm(-1) and 3602 cm(-1) were identified and assigned to strongly, moderately and weakly hydrogen-bonded water molecules, respectively. According to the variation trend of these hydrogen-bonded water molecules, three sections were divided for the adsorption process. Furthermore, the molecular structure of water absorbed by hydrophilic groups of wood in each section was demonstrated. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Mathematical Modelling of Nitrate Removal from Water Using a Submerged Membrane Adsorption Hybrid System with Four Adsorbents

    Directory of Open Access Journals (Sweden)

    Mahatheva Kalaruban

    2018-01-01

    Full Text Available Excessive concentrations of nitrate in ground water are known to cause human health hazards. A submerged membrane adsorption hybrid system that includes a microfilter membrane and four different adsorbents (Dowex 21K XLT ion exchange resin (Dowex, Fe-coated Dowex, amine-grafted (AG corn cob and AG coconut copra operated at four different fluxes was used to continuously remove nitrate. The experimental data obtained in this study was simulated mathematically with a homogeneous surface diffusion model that incorporated membrane packing density and membrane correlation coefficient, and applied the concept of continuous flow stirred tank reactor. The model fit with experimental data was good. The surface diffusion coefficient was constant for all adsorbents and for all fluxes. The mass transfer coefficient increased with flux for all adsorbents and generally increased with the adsorption capacity of the adsorbents.

  20. A Novel Nanohybrid Nanofibrous Adsorbent for Water Purification from Dye Pollutants

    Directory of Open Access Journals (Sweden)

    Shahin Homaeigohar

    2016-10-01

    Full Text Available In this study, we devised a novel nanofibrous adsorbent made of polyethersulfone (PES for removal of methylene blue (MB dye pollutant from water. The polymer shows a low isoelectric point thus at elevated pHs and, being nanofibrous, can offer a huge highly hydroxylated surface area for adsorption of cationic MB molecules. As an extra challenge, to augment the adsorbent’s properties in terms of adsorption capacity in neutral and acidic conditions and thermal stability, vanadium pentoxide (V2O5 nanoparticles were added to the nanofibers. Adsorption data were analyzed according to the Freundlich adsorption model. The thermodynamic parameters verified that only at basic pH is the adsorption spontaneous and in general the process is entropy-driven and endothermic. The kinetics of the adsorption process was evaluated by the pseudo-first- and pseudo-second-order models. The latter model exhibited the highest correlation with data. In sum, the adsorbent showed a promising potential for dye removal from industrial dyeing wastewater systems, especially when envisaging their alkaline and hot conditions.

  1. Activated carbons and low cost adsorbents for remediation of tri- and hexavalent chromium from water.

    Science.gov (United States)

    Mohan, Dinesh; Pittman, Charles U

    2006-09-21

    Hexavalent chromium is a well-known highly toxic metal, considered a priority pollutant. Industrial sources of Cr(VI) include leather tanning, cooling tower blowdown, plating, electroplating, anodizing baths, rinse waters, etc. The most common method applied for chromate control is reduction of Cr(VI) to its trivalent form in acid (pH approximately 2.0) and subsequent hydroxide precipitation of Cr(III) by increasing the pH to approximately 9.0-10.0 using lime. Existing overviews of chromium removal only cover selected technologies that have traditionally been used in chromium removal. Far less attention has been paid to adsorption. Herein, we provide the first review article that provides readers an overview of the sorption capacities of commercial developed carbons and other low cost sorbents for chromium remediation. After an overview of chromium contamination is provided, more than 300 papers on chromium remediation using adsorption are discussed to provide recent information about the most widely used adsorbents applied for chromium remediation. Efforts to establish the adsorption mechanisms of Cr(III) and Cr(VI) on various adsorbents are reviewed. Chromium's impact environmental quality, sources of chromium pollution and toxicological/health effects is also briefly introduced. Interpretations of the surface interactions are offered. Particular attention is paid to comparing the sorption efficiency and capacities of commercially available activated carbons to other low cost alternatives, including an extensive table.

  2. Extraction of triazole fungicides in environmental waters utilizing poly (ionic liquid)-functionalized magnetic adsorbent.

    Science.gov (United States)

    Liu, Cheng; Liao, Yingmin; Huang, Xiaojia

    2017-11-17

    This work prepared a new poly (ionic liquid)-functionalized magnetic adsorbent (PFMA) for the extraction of triazole fungicides (TFs) in environmental waters prior to determination by high performance liquid chromatography/diode array detection (HPLC-DAD). A polymerizable ionic liquid, 1-methyl-3-allylimidazolium bis(trifluoromethylsulfonyl)imide was employed to copolymerize with divinylbenzene on the surface of modified magnetite to fabricate the PFMA. The morphology, spectroscopic and magnetic properties of the new adsorbent were investigated by different techniques. A series of key parameters that influence the extraction performance including the amount of PFMA, desorption solvent, adsorption and desorption time, sample pH value and ionic strength were optimized in detail. Under the optimum conditions, the prepared PFMA could extract targeted TFs effectively and quickly under the format of magnetic solid-phase extraction (MSPE). Satisfactory linearities were achieved in the range of 0.1-200.0μg/L for triadimenol and 0.05-200.0μg/L for other TFs with good coefficients of determination above 0.99 for all analytes. The limits of detection (S/N=3) and limits of quantification (S/N=10) for TFs were in the range of 0.0050-0.0078μg/L and 0.017-0.026μg/L, respectively. Environmental waters including lake, river and well waters were used to demonstrate the applicability of developed MSPE-HPLC-DAD method, and satisfactory recoveries and repeatability were obtained. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Magnetite nanoparticles coated with methoxy polyethylene glycol as an efficient adsorbent of diazinon pesticide from water

    Directory of Open Access Journals (Sweden)

    Mahboubeh Saeidi

    2016-12-01

    Full Text Available Methoxy polyethylene glycol modified magnetite nanoparticles (PEGMNs were synthesized and characterized by scanning electron microscopy (SEM, vibrating sample magnetometer (VSM, and X-ray diffraction (XRD. The adsorption of diazinon onto PEGMNs was investigated by UV-Vis spectrophotometry at 236 nm, through batch experiments. The effects of adsorbent dosage, solution pH, contact time, solution temperature and water impurities on the adsorption of diazinon onto PEGMNs were investigated. The process of adsorption was increased rapidly in the first contact period of 10 min. The adsorption at equilibrium (qe was found to increase with increasing pH. The results of diazinon removal at various PEGMNs dosages demonstrated that the optimum dose of PEGMNs was 1mg. The amount of adsorption of diazinon at equilibrium increased with an increasing temperature from 15°C to 45°C that indicateds an endothermic process. Therefore, PEGMNs were used as an efficient absorbent for the removal of diazinon.

  4. Arsenic adsorption and speciation in drinking water by GAC-based iron-containing adsorbents

    Science.gov (United States)

    Gim, Yewon; Terry, Jeff; Gu, Zhimang; Hua, B.; Deng, Baolin

    2008-04-01

    Granular Activated Carbon (GAC) with Iron adsorbents were developed for effective removal of arsenic from drinking water. The structure and proposed mechanism for As removal was studied using X-ray absorption spectroscopy. The oxidation state of As(III)GAC sample was calculated using XANES spectra and verified to be predominantly As(V). The structure was determined using EXAFS spectra of As(V) and Fe. The Fe spectra suggested thin layer of Fe oxide formation on GAC surface. As data showed As oxide formed bond on the Fe oxide surface. The spectra were calculated using multiple geometrically optimized models calculated using density functional theory. Further calculations were done to verify the structure, and further examine the structure.

  5. Chemical characterization of agroforestry solid residues aiming its utilization as adsorbents for metals in water

    Directory of Open Access Journals (Sweden)

    Francisco H. M. Luzardo

    2015-01-01

    Full Text Available In this work, a study of the correlation between the functional groups present in the chemical structure of the fibers of coconut shells, cocoa and eucalyptus, and their adsorption capacity of Cd+2 and Cu+2 ions from water was performed. The content of soluble solids and reactive phenols in aqueous extracts were determined. The chemical functional groups present in the fibers were examined using the IR spectra. The adsorption capacity of the peels was determined using atomic absorption spectrophotometer. For Cd+2, a significant correlation between the adsorption capacity and some specific chemical functional groups present in the fiber was verified. The potential use of these peels, as adsorbent of Cd+2 ions, is based on the presence of OH functional groups such as aryl-OH, aryl-O-CH2 of phenol carboxylic acids, as well as carbonyl groups derived from carboxylic acid salts, in these fibers.

  6. Mussel-inspired synthesis of polydopamine-functionalized graphene hydrogel as reusable adsorbents for water purification.

    Science.gov (United States)

    Gao, Hongcai; Sun, Yimin; Zhou, Jiajing; Xu, Rong; Duan, Hongwei

    2013-01-23

    We present a one-step approach to polydopamine-modified graphene hydrogel, with dopamine serving as both reductant and surface functionalization agents. The synthetic method is based on the spontaneous polymerization of dopamine and the self-assembly of graphene nanosheets into porous hydrogel structures. Benefiting from the abundant functional groups of polydopamine and the high specific surface areas of graphene hydrogel with three-dimensional interconnected pores, the prepared material exhibits high adsorption capacities toward a wide spectrum of contaminants, including heavy metals, synthetic dyes, and aromatic pollutants. Importantly, the free-standing graphene hydrogel can be easily removed from water after adsorption process, and can be regenerated by altering the pH values of the solution for adsorbed heavy metals or using low-cost alcohols for synthetic dyes and aromatic molecules.

  7. Rapid removal of aniline from contaminated water by a novel polymeric adsorbent.

    Science.gov (United States)

    Huang, Yunhong; Xu, Yang; He, Qinghua; Cao, Yusheng; Du, Bibai

    2014-01-01

    Dummy molecularly imprinted polymers (DMIPs) for aniline were synthesized by a thermal polymerization method using acrylamide as a functional monomer, ethylene dimethacrylate as a crosslinker, 2,2-azobisisobutyronitrile as a free radical initiator, acetonitrile as a porogenic solvent, and analogues of aniline, namely sulfadiazine, as the template. The DMIPs that were obtained showed a high affinity to aniline compared to non-imprinted polymers. It was proven that the DMIPs obtained using sulfadiazine as the template were much better than the molecularly imprinted polymers using aniline as the template. The results indicated that the Freundlich model was fit for the adsorption model of DMIP for aniline and the adsorption model of the DMIP for aniline was multilayer adsorption. Furthermore, the results showed that the DMIP synthesized by bulk polymerization could be used as a novel adsorbent for removal of aniline from contaminated water.

  8. Influence of cations on catalytic properties of silica gel in radiolysis of adsorbed water molecules. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Garibov, A.A.; Melikzade, M.M.; Bakirov, M.Ya.; Ramazanova, M.Kh.

    Kinetics of hydrogen formation during gamma-radiolysis of water, adsorbed on the surface of silica gels: KSK, hyghly pure SiO/sub 2/-J and its SiO/sub 2/-Ca, SiO/sub 2/-Al cation exchange forms has been studied. Of all the studied samples SiO/sub 2/-Al possesses the highest catalytic activity. It is established that temperature increase from 25 to 250 deg causes the decrease in radiation-chemical yield of hydrogen molecules from 1.12 to 0.28 per 100 eV of energy, absorbed in system KSK/sup +/ adsorbed water.

  9. Nanostructured Fe2O3/Al2O3 Adsorbent for removal of As (V from water

    Directory of Open Access Journals (Sweden)

    Faranak Akhlaghian

    2017-04-01

    Full Text Available The presence of arsenate in drinking water causes adverse health effects including skin lesions, diabetes, cancer, damage to the nervous system, and cardiovascular diseases. Therefore, the removal of As (V from water is necessary. In this work, nanostructured adsorbent Fe2O3/Al2O3 was synthesized via the sol-gel method and applied to remove arsenate from polluted waters. First, the Fe2O3 load of the adsorbent was optimized. The Fe2O3/Al2O3 adsorbent was characterized by means of XRF, XRD, ASAP, and SEM techniques. The effects of the operating conditions of the batch process of As (V adsorption such as pH, adsorbent dose, contact time, and initial concentration of As (V solution were studied, and optimized. The thermodynamic study of the process showed that arsenate adsorption was endothermic. The kinetic model corresponded to the pseudo-second-order model. The Langmuir adsorption isotherm was better fitted to the experimental data. The Fe2O3/Al2O3 adsorbent was immobilized on leca granules and applied for As (V adsorption. The results showed that the immobilization of Fe2O3/Al2O3 on leca particles improved the As (V removal efficiency.

  10. Removal efficiency of water purifier and adsorbent for iodine, cesium, strontium, barium and zirconium in drinking water.

    Science.gov (United States)

    Sato, Itaru; Kudo, Hiroaki; Tsuda, Shuji

    2011-01-01

    The severe incident of Fukushima Daiichi Nuclear Power Station has caused radioactive contamination of environment including drinking water. Radioactive iodine, cesium, strontium, barium and zirconium are hazardous fission products because of the high yield and/or relatively long half-life. In the present study, 4 pot-type water purifiers and several adsorbents were examined for the removal effects on these elements from drinking water. Iodide, iodate, cesium and barium were removed by all water purifiers with efficiencies about 85%, 40%, 75-90% and higher than 85%, respectively. These efficiencies lasted for 200 l, which is near the recommended limits for use of filter cartridges, without decay. Strontium was removed with initial efficiencies from 70% to 100%, but the efficiencies were slightly decreased by use. Zirconium was removed by two models, but hardly removed by the other models. Synthetic zeolite A4 efficiently removed cesium, strontium and barium, but had no effect on iodine and zirconium. Natural zeolite, mordenite, removed cesium with an efficiency as high as zeolite A4, but the removal efficiencies for strontium and barium were far less than those of zeolite A4. Activated carbon had little removal effects on these elements. In case of radioactive contamination of tap water, water purifiers may be available for convenient decontamination of drinking water in the home.

  11. Water Treatment Technology - Pumps.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on pumps provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: types of pumps in plant and distribution systems, pump…

  12. Water Treatment Technology - Hydraulics.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on hydraulics provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: head loss in pipes in series, function loss in…

  13. Water Treatment Technology - Filtration.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on filtration provides instructional materials for six competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: purposes of sedimentation basins and flocculation…

  14. Water Treatment Technology - Wells.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on wells provides instructional materials for five competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: dug, driven, and chilled wells, aquifer types, deep well…

  15. Water Treatment Technology - Springs.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on springs provides instructional materials for two competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on spring basin construction and spring protection. For each competency, student…

  16. Water Treatment Technology - Chlorination.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on chlorination provides instructional materials for nine competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: purpose and process of chlorination, chlorine…

  17. Water Treatment Technology - Flouridation.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on flouridation provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: purpose and process of flouridation, correct…

  18. Sol-Gel Derived Adsorbents with Enzymatic and Complexonate Functions for Complex Water Remediation.

    Science.gov (United States)

    Pogorilyi, Roman P; Pylypchuk, Ievgen; Melnyk, Inna V; Zub, Yurii L; Seisenbaeva, Gulaim A; Kessler, Vadim G

    2017-09-28

    Sol-gel technology is a versatile tool for preparation of complex silica-based materials with targeting functions for use as adsorbents in water purification. Most efficient removal of organic pollutants is achieved by using enzymatic reagents grafted on nano-carriers. However, enzymes are easily deactivated in the presence of heavy metal cations. In this work, we avoided inactivation of immobilized urease by Cu (II) and Cd (II) ions using magnetic nanoparticles provided with additional complexonate (diethylene triamine pentaacetic acid or DTPA) functions. Obtained nanomaterials were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). According to TGA, the obtained Fe₃O₄/SiO₂-NH₂-DTPA nanoadsorbents contained up to 0.401 mmol/g of DTPA groups. In the concentration range Ceq = 0-50 mmol/L, maximum adsorption capacities towards Cu (II) and Cd (II) ions were 1.1 mmol/g and 1.7 mmol/g, respectively. Langmuir adsorption model fits experimental data in concentration range Ceq = 0-10 mmol/L. The adsorption mechanisms have been evaluated for both of cations. Crosslinking of 5 wt % of immobilized urease with glutaraldehyde prevented the loss of the enzyme in repeated use of the adsorbent and improved the stability of the enzymatic function leading to unchanged activity in at least 18 cycles. Crosslinking of 10 wt % urease on the surface of the particles allowed a decrease in urea concentration in 20 mmol/L model solutions to 2 mmol/L in up to 10 consequent decomposition cycles. Due to the presence of DTPA groups, Cu2+ ions in concentration 1 µmol/L did not significantly affect the urease activity. Obtained magnetic Fe₃O₄/SiO₂-NH₂-DTPA-Urease nanocomposite sorbents revealed a high potential for urease decomposition, even in presence of heavy metal ions.

  19. Sol-Gel Derived Adsorbents with Enzymatic and Complexonate Functions for Complex Water Remediation

    Directory of Open Access Journals (Sweden)

    Roman P. Pogorilyi

    2017-09-01

    Full Text Available Sol-gel technology is a versatile tool for preparation of complex silica-based materials with targeting functions for use as adsorbents in water purification. Most efficient removal of organic pollutants is achieved by using enzymatic reagents grafted on nano-carriers. However, enzymes are easily deactivated in the presence of heavy metal cations. In this work, we avoided inactivation of immobilized urease by Cu (II and Cd (II ions using magnetic nanoparticles provided with additional complexonate (diethylene triamine pentaacetic acid or DTPA functions. Obtained nanomaterials were characterized by Fourier transform infrared spectroscopy (FTIR, thermogravimetric analysis (TGA, and scanning electron microscopy (SEM. According to TGA, the obtained Fe3O4/SiO2-NH2-DTPA nanoadsorbents contained up to 0.401 mmol/g of DTPA groups. In the concentration range Ceq = 0–50 mmol/L, maximum adsorption capacities towards Cu (II and Cd (II ions were 1.1 mmol/g and 1.7 mmol/g, respectively. Langmuir adsorption model fits experimental data in concentration range Ceq = 0–10 mmol/L. The adsorption mechanisms have been evaluated for both of cations. Crosslinking of 5 wt % of immobilized urease with glutaraldehyde prevented the loss of the enzyme in repeated use of the adsorbent and improved the stability of the enzymatic function leading to unchanged activity in at least 18 cycles. Crosslinking of 10 wt % urease on the surface of the particles allowed a decrease in urea concentration in 20 mmol/L model solutions to 2 mmol/L in up to 10 consequent decomposition cycles. Due to the presence of DTPA groups, Cu2+ ions in concentration 1 µmol/L did not significantly affect the urease activity. Obtained magnetic Fe3O4/SiO2-NH2-DTPA-Urease nanocomposite sorbents revealed a high potential for urease decomposition, even in presence of heavy metal ions.

  20. Removal of silica in geothermal water by addition of adsorbents; Kyuchakuzai tenka ni yoru jinetsu suichu no silica no jokyo

    Energy Technology Data Exchange (ETDEWEB)

    Umetsu, Y.; Narita, E.; Nakazawa, H.; Shimizu, K. [Iwate Univ., Morioka (Japan). Faculty of Education

    1997-06-01

    In the scales generated from geothermal wells, there are silica scale, the other carbonates and sulfates of calcium, composite scales containing the sulfides of metals or oxides and so forth, however, in case of Kakkonda geothermal well, the numerous scales contain silica as a major component. As for the measures to prevent the silica scaling, it is summarized to prevent the scale precipitation or to remove silica component previously. In this study, the removal of silicic acid from the geothermal water has been attempted to prevent the silica-scaling by addition of various iron-contained adsorbents to the water at 40degC. The mixing ratio of Fe in adsorbent to Si in geothermal water was 0.5 (mol/mol). The mixture was stirred at 200 rpm for 5 to 60 min. When allophane clay, tuff-mudstone or iron hydroxide sludge was used as adsorbents, residual silica concentration in the geothermal water was reduced to 300, 150 and 130 mg/l after 10-min. stirring, respectively. Consequently, iron hydroxide sludge and tuff-mudstone re estimated as a useful adsorbent. 20 refs., 8 figs., 2 tabs.

  1. Mn-Ce oxide as a high-capacity adsorbent for fluoride removal from water.

    Science.gov (United States)

    Deng, Shubo; Liu, Han; Zhou, Wei; Huang, Jun; Yu, Gang

    2011-02-28

    A novel Mn-Ce oxide adsorbent with high sorption capacity for fluoride was prepared via co-precipitation method in this study, and the granular adsorbent was successfully prepared by calcining the mixture of the Mn-Ce powder and pseudo-boehmite. High-resolution transmission electron microscopy (TEM) image showed that the Mn-Ce adsorbent consisted of about 4.5 nm crystals, and X-ray diffraction (XRD) analysis indicated the formation of solid solution by Mn species entering CeO(2) lattices. The surface hydroxyl group density on the Mn-Ce adsorbent was determined to be as high as 15.3 mmol g(-1), mainly responsible for its high sorption capacity for fluoride. Sorption isotherms showed that the sorption capacities of fluoride on the powdered and granular adsorbent were 79.5 and 45.5 mg g(-1) respectively at the equilibrium fluoride concentration of 1 mg L(-1), much higher than all reported adsorbents. Additionally, the adsorption was fast within the initial 1 h. Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis revealed that the hydroxyl groups on the adsorbent surface were involved in the sorption of fluoride. Both anion exchange and electrostatic interaction were involved in the sorption of fluoride on the Mn-Ce oxide adsorbent. Copyright © 2010 Elsevier B.V. All rights reserved.

  2. The influence of white and blue silica gels as adsorbents in adsorptive-distillation of ethanol-water mixture

    Science.gov (United States)

    Megawati, Jannah, Reni Ainun; Rahayuningtiyas, Indi

    2017-01-01

    This research studied the difference of white and blue silica gels when used as an adsorbent for ethanol purification that is processed via Adsorptive-Distillation (AD) at 1 atm pressure. The effect of process duration to purification process is also recorded and studied to evaluate the performance of designed AD equipment. The experiment was conducted using boiling flask covered with a heating mantle and the temperature was maintained at 78°C. The vapour flowed into the adsorbent column and was condensed using water as a cooling medium. The initial ethanol concentration was 90.8% v/v and volume was 300 mL. Experiment shows that designed AD equipment could be used to purify ethanol. The average vapour velocity was about 39.29 and 45.91 m/s for white and blue silica gels, respectively, which is considered very high. Therefore the saturated adsorption could not be obtained. Highest ethanol concentration achieved using white silica gel is about 96.671% v/v after 50 minutes. Thus AD with white silica gel showed good performance and passed azeotropic point. But AD with blue silica gel showed a different result, the adsorption of blue silica gel failed to break the azeotropic point. The outlet average water concentration for white and blue silica gels is 3.54 and 3.42 mole/L. Based on the weight ratio of adsorbed water per adsorbent, at 55th minutes of time; this ratio of blue silica gel is about 0.053 gwater/gads. The time required by the blue silica to achieve 0.5 wwater-adsorbed/wwater-initial is 45 minutes, and the average outlet water concentration is 3.42 mole/L. Meanwhile, the time required by a white silica to complete 0.5 wwater-adsorbed/wwater-initial is 35 minutes, and the average outlet water level is 3.54 mole/L. Based on the results, the blue silica as an adsorbent for AD of ethanol-water mixture is better than white silica gel.

  3. Valorization of solid waste products from olive oil industry as potential adsorbents for water pollution control--a review.

    Science.gov (United States)

    Bhatnagar, Amit; Kaczala, Fabio; Hogland, William; Marques, Marcia; Paraskeva, Christakis A; Papadakis, Vagelis G; Sillanpää, Mika

    2014-01-01

    The global olive oil production for 2010 is estimated to be 2,881,500 metric tons. The European Union countries produce 78.5% of the total olive oil, which stands for an average production of 2,136,000 tons. The worldwide consumption of olive oil increased of 78% between 1990 and 2010. The increase in olive oil production implies a proportional increase in olive mill wastes. As a consequence of such increasing trend, olive mills are facing severe environmental problems due to lack of feasible and/or cost-effective solutions to olive-mill waste management. Therefore, immediate attention is required to find a proper way of management to deal with olive mill waste materials in order to minimize environmental pollution and associated health risks. One of the interesting uses of solid wastes generated from olive mills is to convert them as inexpensive adsorbents for water pollution control. In this review paper, an extensive list of adsorbents (prepared by utilizing different types of olive mill solid waste materials) from vast literature has been compiled, and their adsorption capacities for various aquatic pollutants removal are presented. Different physicochemical methods that have been used to convert olive mill solid wastes into efficient adsorbents have also been discussed. Characterization of olive-based adsorbents and adsorption mechanisms of various aquatic pollutants on these developed olive-based adsorbents have also been discussed in detail. Conclusions have been drawn from the literature reviewed, and suggestions for future research are proposed.

  4. Benzotriazole removal from water by Zn-Al-O binary metal oxide adsorbent: behavior, kinetics and mechanism.

    Science.gov (United States)

    Xu, Bingbing; Wu, Fengchang; Zhao, Xiaoli; Liao, Haiqing

    2010-12-15

    In this study, a novel Zn-Al-O binary metal oxide adsorbent was prepared and used to remove the emerging polar contaminant benzotriazole from water. The adsorption behavior, kinetics and mechanism were systemically studied. Results showed that benzotriazole was rapidly and effectively adsorbed by the adsorbent. Instantaneous adsorption was observed under each studied condition, and the adsorption reached equilibrium within 30 min. High initial benzotriazole concentration enhanced the adsorption. The amount of absorbed benzotriazole increased with increasing adsorbent dosage, but decreased with increasing ionic strength. Solution pH had little effect on benzotriazole adsorption. The adsorption isotherm was consistent with S-type. Langmuir isotherm model fitted the equilibrium data better than Freundlich, Dubinin-Radushkevich and Temkin isotherm models. The maximum monolayer adsorptive capacity of benzotriazole with and without electrolytes was 7.30 mg g(-1) and 9.51 mg g(-1), respectively. Elovich and pseudo-second-order models were most suitable for describing the adsorption kinetics. Interactions between the surface sites of the adsorbent and benzotriazole may be a combination of electrostatic interaction, ion exchange and hydrogen bond. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. Sludge from paper mill effluent treatment as raw material to produce carbon adsorbents: An alternative waste management strategy.

    Science.gov (United States)

    Jaria, Guilaine; Silva, Carla Patrícia; Ferreira, Catarina I A; Otero, Marta; Calisto, Vânia

    2017-03-01

    Pulp and paper industry produces massive amounts of sludge from wastewater treatment, which constitute an enormous environmental challenge. A possible management option is the conversion of sludge into carbon-based adsorbents to be applied in water remediation. For such utilization it is important to investigate if sludge is a consistent raw material originating reproducible final materials (either over time or from different manufacturing processes), which is the main goal of this work. For that purpose, different primary (PS) and biological sludge (BS) batches from two factories with different operation modes were sampled and subjected to pyrolysis (P materials) and to pyrolysis followed by acid washing (PW materials). All the materials were characterized by proximate analysis, total organic carbon (TOC) and inorganic carbon (IC), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and N2 adsorption isotherms (specific surface area (SBET)and porosity determination). Sludge from the two factories proved to have distinct physicochemical properties, mainly in what concerns IC. After pyrolysis, the washing step was essential to reduce IC and to considerably increase SBET, yet with high impact in the final production yield. Among the materials here produced, PW materials from PS were those having the highest SBET values (387-488 m2 g-1). Overall, it was found that precursors from different factories might originate final materials with distinct characteristics, being essential to take into account this source of variability when considering paper mill sludge as a raw material. Nevertheless, for PS, low variability was found between batches, which points out to the reliability of such residues to be used as precursors of carbon adsorbents. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Treatment with activated carbon and other adsorbents as an effective method for the removal of volatile compounds in agricultural distillates.

    Science.gov (United States)

    Balcerek, Maria; Pielech-Przybylska, Katarzyna; Patelski, Piotr; Dziekońska-Kubczak, Urszula; Jusel, Tomaš

    2017-05-01

    This study investigates the effect of treatment with activated carbon and other adsorbents on the chemical composition and organoleptics of a barley malt-based agricultural distillate. Contact with activated carbon is one of the methods by which the quality of raw distillates and spirit beverages can be improved. Samples placed in contact with 1 g activated carbon (SpiritFerm) per 100 ml distillate with ethanol content of 50% v/v for 1 h showed the largest reductions in the concentrations of most volatile compounds (aldehydes, alcohols, esters). Increasing the dose of adsorbent to over 1 g 100 ml -1 did not improve the purity of the agricultural distillate significantly. Of the tested compounds, acetaldehyde and methanol showed the lowest adsorption on activated carbon. The lowest concentrations of these congeners (expressed in mg l -1 alcohol 100% v/v) were measured in solutions with ethanol contents of 70-80% v/v, while solutions with an alcoholic strength by volume of 40% did not show statistically significant decreases in these compounds in relation the control sample. The reductions in volatile compounds were compared with those for other adsorbents based on silica or activated carbon and silica. An interesting alternative to activated carbon was found to be an adsorbent prepared from activated carbon and silica (Spiricol). Treatment with this adsorbent produced distillate with the lowest concentrations of acetaldehyde and isovaleraldehyde, and led to the greatest improvement in its organoleptics.

  7. Adsorbent synthesis of polypyrrole/TiO(2) for effective fluoride removal from aqueous solution for drinking water purification: Adsorbent characterization and adsorption mechanism.

    Science.gov (United States)

    Chen, Jie; Shu, Chiajung; Wang, Ning; Feng, Jiangtao; Ma, Hongyu; Yan, Wei

    2017-06-01

    More than 20 countries are still suffering problems of excessive fluoride containing water, and greater than 8mg/L fluoride groundwater has been reported in some villages in China. In order to meet the challenge in the drinking water defluoridation engineering, a high efficiency and affinity defluoridation adsorbent PPy/TiO 2 composite was designed and synthetized by in-situ chemical oxidative polymerization. Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction Investigator (XRD), X-ray photoelectron spectroscopy (XPS), Thermogravimetric analysis (TG), N 2 isotherm analysis, Scanning Electron Microscopy (SEM) and Zeta potential analysis were conducted to characterize surface and textural properties of the as-prepared PPy/TiO 2 , and the possibility of fluoride adsorption was carefully estimated by adsorption isotherm and kinetic studies. Characterization investigations demonstrate the uniqueness of surface and textural properties, such as suitable specific surface area and abundant positively charged nitrogen atoms (N + ), which indicate the composite is a suitable material for the fluoride adsorption. Adsorption isotherms and kinetics follow better with Langmuir and pseudo-second-order model, respectively. The maximum adsorption capacity reaches 33.178mg/g at 25°C according to Langmuir model, and particular interest was the ability to reduce the concentration of fluoride from 11.678mg/L to 1.5mg/L for drinking water at pH of 7 within 30min. Moreover, the adsorbent can be easily recycled without the loss of adsorption capacity after six cycles, greatly highlighting its outstanding affinity to fluoride, low-cost and novel to be used in the purification of fluoride containing water for drinking. Furthermore, the adsorption mechanism was extensively investigated and discussed by FTIR investigation and batch adsorption studies including effect of pH, surface potential and thermodynamics. The adsorption is confirmed to be a spontaneous and exothermic

  8. Preparation of Al-Ce hybrid adsorbent and its application for defluoridation of drinking water

    Energy Technology Data Exchange (ETDEWEB)

    Liu Han [Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China); Deng Shubo, E-mail: dengshubo@tsinghua.edu.cn [Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China); POPs Research Center, Tsinghua University, Beijing 100084 (China); Li Zhijian; Yu Gang; Huang Jun [Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084 (China); POPs Research Center, Tsinghua University, Beijing 100084 (China)

    2010-07-15

    A novel Al-Ce hybrid adsorbent with high sorption capacity for fluoride was prepared through the coprecipitation method in this study, and its preparation conditions were optimized. X-ray diffraction (XRD) and scanning electron microscope (SEM) results showed that the hybrid adsorbent was of amorphous structure and constituted by some aggregated nanoparticles. As the adsorbent had the zero point of {zeta} potential at pH 9.6, it was very effective in fluoride removal from aqueous solution via electrostatic interaction. The results of sorption experiments including sorption kinetics, isotherms, and the effect of solution pH showed that the sorption of fluoride on the Al-Ce adsorbent was fast and pH-dependent. Especially, the adsorbent had high sorption capacity up to 27.5 mg g{sup -1} for fluoride at the equilibrium fluoride concentration of 1 mg L{sup -1}, much higher than that of the conventional adsorbents. Fourier transform infrared (FTIR) analysis and zeta potential measurement showed that the hydroxyl groups and the protonated hydroxyl groups on the adsorbent surface were involved in the fluoride adsorption.

  9. Preparation of Al-Ce hybrid adsorbent and its application for defluoridation of drinking water.

    Science.gov (United States)

    Liu, Han; Deng, Shubo; Li, Zhijian; Yu, Gang; Huang, Jun

    2010-07-15

    A novel Al-Ce hybrid adsorbent with high sorption capacity for fluoride was prepared through the coprecipitation method in this study, and its preparation conditions were optimized. X-ray diffraction (XRD) and scanning electron microscope (SEM) results showed that the hybrid adsorbent was of amorphous structure and constituted by some aggregated nanoparticles. As the adsorbent had the zero point of zeta potential at pH 9.6, it was very effective in fluoride removal from aqueous solution via electrostatic interaction. The results of sorption experiments including sorption kinetics, isotherms, and the effect of solution pH showed that the sorption of fluoride on the Al-Ce adsorbent was fast and pH-dependent. Especially, the adsorbent had high sorption capacity up to 27.5 mg g(-1) for fluoride at the equilibrium fluoride concentration of 1 mg L(-1), much higher than that of the conventional adsorbents. Fourier transform infrared (FTIR) analysis and zeta potential measurement showed that the hydroxyl groups and the protonated hydroxyl groups on the adsorbent surface were involved in the fluoride adsorption. 2010 Elsevier B.V. All rights reserved.

  10. Coordination structure of adsorbed Zn(II) at Water-TiO2 interfaces

    Energy Technology Data Exchange (ETDEWEB)

    He, G.; Pan, G.; Zhang, M.; Waychunas, G.A.

    2011-01-15

    The local structure of aqueous metal ions on solid surfaces is central to understanding many chemical and biological processes in soil and aquatic environments. Here, the local coordination structure of hydrated Zn(II) at water-TiO{sub 2} interfaces was identified by extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) spectroscopy combined with density functional theory (DFT) calculations. A nonintegral coordination number of average {approx}4.5 O atoms around a central Zn atom was obtained by EXAFS analysis. DFT calculations indicated that this coordination structure was consistent with the mixture of 4-coordinated bidentate binuclear (BB) and 5-coordinated bidentate mononuclear (BM) metastable equilibrium adsorption (MEA) states. The BB complex has 4-coordinated Zn, while the monodentate mononuclear (MM) complex has 6-coordinated Zn, and a 5-coordinated adsorbed Zn was found in the BM adsorption mode. DFT calculated energies showed that the lower-coordinated BB and BM modes were thermodynamically more favorable than the higher-coordinated MM MEA state. The experimentally observed XANES fingerprinting provided additional direct spectral evidence of 4- and 5-coordinated Zn-O modes. The overall spectral and computational evidence indicated that Zn(II) can occur in 4-, 5-, and 6-oxygen coordinated sites in different MEA states due to steric hindrance effects, and the coexistence of different MEA states formed the multiple coordination environments.

  11. EDTA functionalized magnetic nanoparticle as a multifunctional adsorbent for Congo red dye from contaminated water

    Science.gov (United States)

    Sahoo, Jitendra Kumar; Rath, Juhi; Dash, Priyabrat; Sahoo, Harekrushna

    2017-05-01

    The present work reports the applicability of magnetite iron nanoparticles (Fe3O4) functionalized with ethylenediaminetetraacetic acid (EDTA) as an efficient adsorbent for the removal of Congo red (CR) dye from contaminated water. Magnetic nanoparticles (Fe3O4) are prepared by chemical precipitation method in which Fe2+ and Fe3+ salt from aqueous solution were reacted in presence of ammonia solution. The surface of Fe3O4 nanoparticle was first coated with (3-aminopropyl) triethoxy silane (APTES) by a salinization reaction and then linked with EDTA via reaction between -NH2 and -COOH to form well dispersed surface functionalised biocompatible magnetic nanoparticles. The obtained EDTA functionalized magnetic nanoparticles are characterized in terms of their morphological, XRD, BET surface area analysis, Fourier transform infrared spectroscopy (FT-IR) and Vibrating sample magnetometer (VSM). The adsorption of CR on Fe3O4-APTES-EDTA nanocomposite corresponds well to the Langmuir model and the Freundlich model respectively. The adsorption processes for CR followed the pseudo-second-order model.

  12. Treatment of Wastewater from a Dairy Industry Using Rice Husk as Adsorbent: Treatment Efficiency, Isotherm, Thermodynamics, and Kinetics Modelling

    Directory of Open Access Journals (Sweden)

    Uttarini Pathak

    2016-01-01

    Full Text Available Effluent from milk processing unit contains soluble organics, suspended solids, and trace organics releasing gases, causing taste and odor, and imparting colour and turbidity produced as a result of high consumption of water from the manufacturing process, utilities and service section, chemicals, and residues of technological additives used in individual operations which makes it crucial matter to be treated for preserving the aesthetics of the environment. In this experimental study after determination of the initial parameters of the raw wastewater it was subjected to batch adsorption study using rice husk. The effects of contact time, initial wastewater concentration, pH, adsorbent dosage, solution temperature and the adsorption kinetics, isotherm, and thermodynamic parameters were investigated. The phenomenon of adsorption was favoured at a lower temperature and lower pH in this case. Maximum removal as high as 92.5% could be achieved using an adsorbent dosage of 5 g/L, pH of 2, and temperature of 30°C. The adsorption kinetics and the isotherm studies showed that the pseudo-second-order model and the Langmuir isotherm were the best choices to describe the adsorption behavior. The thermodynamic parameters suggested that not only was the adsorption by rice husk spontaneous and exothermic in nature but also the negative entropy change indicated enthalpy driven process.

  13. Molecular organization of hydrophobic molecules and co-adsorbed water in SBA-15 ordered mesoporous silica material.

    Science.gov (United States)

    Mellaerts, Randy; Roeffaers, Maarten B J; Houthoofd, Kristof; Van Speybroeck, Michiel; De Cremer, Gert; Jammaer, Jasper A G; Van den Mooter, Guy; Augustijns, Patrick; Hofkens, Johan; Martens, Johan A

    2011-02-21

    The purpose of this study was to improve our understanding of the molecular organization of hydrophobic guest molecules in the presence of co-adsorbed water inside SBA-15 ordered mesoporous silica material. Understanding this adsorption competition is essential in the development of applications of controlled adsorption and desorption. The poorly water soluble drug compound itraconazole and the fluorescent probe Nile red were selected for the study. The interaction between itraconazole and SBA-15 was investigated using FT-IR, (1)H MAS NMR and (29)Si MAS NMR spectroscopy, by determination of adsorption isotherms and release kinetics in simulated gastric fluid. The distribution and migration of the hydrophobic fluorescent probe Nile red was visualized in situ using confocal fluorescence microscopy. For both molecules, there was a pronounced influence of the co-adsorbed water on adsorption, hydrophobic aggregation and migration in SBA-15 pores. These insights contribute to the development of practical methods for loading ordered mesoporous silica materials with hydrophobic molecules.

  14. Removal of microcystin-LR from drinking water using a bamboo-based charcoal adsorbent modified with chitosan.

    Science.gov (United States)

    Zhang, Hangjun; Zhu, Guoying; Jia, Xiuying; Ding, Ying; Zhang, Mi; Gao, Qing; Hu, Ciming; Xu, Shuying

    2011-01-01

    A new kind of low-cost syntactic adsorbent from bamboo charcoal and chitosan was developed for the removal of microcystin-LR from drinking water. Removal efficiency was higher for the syntactic adsorbent when the amount of bamboo charcoal was increased. The optimum dose ratio of bamboo charcoal to chitosan was 6:4, and the optimum amount was 15 mg/L; equilibrium time was 6 hr. The adsorption isotherm was non-linear and could be simulated by the Freundlich model (R2 = 0.9337). Adsorption efficiency was strongly affected by pH and natural organic matter (NOM). Removal efficiency was 16% higher at pH 3 than at pH 9. Efficiency rate was reduced by 15% with 25 mg/L NOM (UV254 = 0.089 cm(-1)) in drinking water. This study demonstrated that the bamboo charcoal modified with chitosan can effectively remove microcystin-LR from drinking water.

  15. Basic Water Treatment Operation.

    Science.gov (United States)

    Ontario Ministry of the Environment, Toronto.

    This manual was developed for use at workshops designed to introduce the fundamentals of water treatment plant operations. The course consists of lecture-discussions and hands-on activities. Each of the fourteen lessons in this document has clearly stated behavioral objectives to tell the trainee what he should know or do after completing that…

  16. Experience With Molecular Adsorbent Recirculating System Treatment in 20 Children Listed for High-Urgency Liver Transplantation

    NARCIS (Netherlands)

    Lexmond, Willem S.; Van Dael, Carin M. L.; Scheenstra, Rene; Goorhuis, Joanne F.; Sieders, Egbert; Verkade, Henkjan J.; Van Rheenen, Patrick F.; Komhoff, Martin

    For more than 10 years, children at our national center for pediatric liver transplantation (LT) have been treated with Molecular Adsorbent Recirculating System (MARS) liver dialysis as a bridging therapy to high-urgency LT. Treatment was reserved for 20 patients with the highest degrees of hepatic

  17. The use of date palm as a potential adsorbent for wastewater treatment: a review.

    Science.gov (United States)

    Ahmad, Tanweer; Danish, Mohammad; Rafatullah, Mohammad; Ghazali, Arniza; Sulaiman, Othman; Hashim, Rokiah; Ibrahim, Mohamad Nasir Mohamad

    2012-06-01

    In tropical countries, the palm tree is one of the most abundant and important trees. Date palm is a principal fruit grown in many regions of the world. It is abundant, locally available and effective material that could be used as an adsorbent for the removal of different pollutants from aqueous solution. This article presents a review on the role of date palm as adsorbents in the removal of unwanted materials such as acid and basic dyes, heavy metals, and phenolic compounds. Many studies on adsorption properties of various low cost adsorbent, such as agricultural waste and activated carbons based on agricultural waste have been reported in recent years. Studies have shown that date palm-based adsorbents are the most promising adsorbents for removing unwanted materials. No previous review is available where researchers can get an overview of the adsorption capacities of date palm-based adsorbent used for the adsorption of different pollutants. This review provides the recent literature demonstrating the usefulness of date palm biomass-based adsorbents in the adsorption of various pollutants.

  18. Assessment of upscaling potential of alternative adsorbent materials for highway stormwater treatment in cold climates.

    Science.gov (United States)

    Ilyas, Aamir; Muthanna, Tone M

    2017-03-01

    Generally, studies on alternative adsorbents focus on adsorbent removal capacity, as a function of pollutant concentration, and other practical aspects, such as costs, environmental impact and end of life costs, that can affect the upscaling of adsorbents for real-life applications, are not explicitly considered. Therefore, this study combines multi-criteria modeling with experimental evaluation to integrate both technical and non-technical factors in assessing the upscaling potential of alternative adsorbents. The experimental step was used to verify the reported pollutant removal as well as testing environmental stability, of the alternative adsorbents, in cold climates. Important factors/criteria for the upscaling process were identified with the help of principal component analysis. The results indicated that adsorbents such as pine bark, olivine and charcoal were the best available options for upscaling. The statistical analysis revealed that factors such as initial costs, hydraulic loads and end-of-life costs were important for the upscaling process and, therefore, should be explicitly included in any future evaluation of the alternative adsorbents.

  19. Expanded graphite loaded with lanthanum oxide used as a novel adsorbent for phosphate removal from water: performance and mechanism study.

    Science.gov (United States)

    Zhang, Ling; Gao, Yan; Li, Mengxue; Liu, Jianyong

    2015-01-01

    A novel adsorbent of expanded graphite (EG) loaded with lanthanum oxide (EG-LaO) was prepared for phosphate removal from water and characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. The effects of impregnation time, La3+ concentration, activation time, and activation temperature on the phosphate removal performance of the adsorbent were studied for optimization of preparation conditions. Isothermal adsorption studies suggested that the Langmuir model fits the experimental data well. Adsorption kinetics investigation showed that the pseudo-second-order model fits the experimental data quite well, indicating that the adsorption process is mainly a process of chemical adsorption, and chloride ions compete to react with the active sites of the adsorbent but do not prevent phosphate from adsorbing onto EG-LaO. The adsorption mechanism studies were performed by a pH dependence study of the adsorption amount. The results demonstrated that the probable mechanisms of phosphate adsorption on EG-LaO were electrostatic and Lewis acid-base interactions in addition to ion exchange.

  20. Removal of Arsenite from Water by Ce-Al-Fe Trimetal Oxide Adsorbent: Kinetics, Isotherms, and Thermodynamics

    Directory of Open Access Journals (Sweden)

    Cuizhen Sun

    2016-01-01

    Full Text Available Ce-Al-Fe trimetal oxide adsorbent was prepared. The morphology characteristics of the new adsorbent were analysed by the transmission electron microscope (SEM method. The SEM results implied its ability in the adsorption of As (III. To verify the analyses, bench-scale experiments were performed for the removal of As (III from water. In the experiments of adsorption, As (III adsorption capacity of the trimetal oxide adsorbent was presented significantly higher than activated aluminium oxide and activated carbon. As (III adsorption kinetics resembled pseudo-second-order adsorption mode. When initial As (III concentration was 3, 8, and 10 mg·L−1, the maximum adsorption capacity achieved was 1.48, 3.73, and 5.12 mg·g−1, respectively. In addition, the experimental adsorption data were described well by the Freundlich adsorption isotherm model at 20, 30, and 40°C. The enthalpy change (ΔS, the standard free energy (ΔG, and entropy change (ΔH indicated that the nature of As (III adsorption was exothermic and spontaneous with increasing randomness on the interface of solid and liquid. And the adsorption mechanism can be interpreted as chemisorption with As (III multilayer coverage formation on the adsorbent surface.

  1. Investigation of lanthanum impregnated cellulose, derived from biomass, as an adsorbent for the removal of fluoride from drinking water.

    Science.gov (United States)

    Nagaraj, Ammavasi; Sadasivuni, Kishor Kumar; Rajan, Mariappan

    2017-11-15

    High concentrations of fluoride in drinking water can cause the disease fluorosis. Our scope goal is to develop an effective biopolymeric adsorbent for the removal of fluoride to below a specific safety limit set by the World Health Organization. In this study, the natural adsorbent material cellulose was impregnated with lanthanum chloride and effectiveness in adsorbing fluoride was confirmed by FT-IR, XRD, and SEM coupled with EDX techniques. The adsorption data were analyzed by Freundlich, Langmuir, and Redlich-Peterson isotherms. The adsorption on cellulose and Lanthanum impregnated Cellulose (LaC) obeyed the pseudo second order kinetic model and thermodynamic parameters were shows the adsorption process was spontaneous and feasible. The high adsorption capacity of LaC was developed from waste materials through an easy procedure, has potential for application to efficient defluoridation. In future, the potential LaC adsorbent will be used for designing of household defluoridation unit for effective and economical fluoride removal. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Effects of the surface chemistry of macroreticular adsorbents on the adsorption of 1-naphthol/1-naphthylamine mixtures from water.

    Science.gov (United States)

    Zhang, Wei-ming; Chen, Jin-long; Chen, Qun; He, Min-yang; Pan, Bing-cai; Zhang, Quan-xing

    2005-01-01

    The adsorption behaviors of 1-naphthol, 1-naphthylamine and 1-naphthol/1-naphthylamine mixtures in water over two macroreticular adsorbents were investigated in single or binary batch systems at 293 K, 303 K and 313 K respectively. All the adsorption isotherms in the studied systems can be adequately fitted by Langmuir model. In the case of aminated macroreticular adsorbent NDA103, 1-naphthol is adsorbed to a larger extent than 1-naphthylamine; while, the opposite trend is found for nonpolar macroreticular adsorbent NDA100. It is noteworthy that at higher temperature (303 K and 313 K), the total uptake amounts of 1-naphthol and 1-naphthylamine in all binary-component systems are obvious larger than the pure uptake amounts in single-component systems, which is presumably due to the cooperative effect primarily arisen from the hydrogen-bonding interaction between the loaded 1-naphthol and 1-naphthylamine molecules. The simultaneous adsorption systems were confirmed to be helpful to the selective adsorption towards 1-naphthol according to the larger selective index.

  3. Aging of the nanosized photochromic WO3 films and the role of adsorbed water in the photochromism

    Science.gov (United States)

    Gavrilyuk, A. I.

    2016-02-01

    Here it has been reported on aging of the nanosized WO3 film, which is revealed is continuous reduction of the photochromic sensitivity over time. Water molecules physically adsorbed on the film surface from ambient air form donor-acceptor and hydrogen bonds, changing gradually the adsorption state to chemisorption which prevents an access of organic molecules that serve as hydrogen donors by the photochromism. The mechanism of the process has been investigated and discussed. The role of water in the photochromism has been highlighted. The difference in the efficiency for being of a hydrogen donor in the photochromic process between water and organic molecules is discussed.

  4. From illite/smectite clay to mesoporous silicate adsorbent for efficient removal of chlortetracycline from water.

    Science.gov (United States)

    Wang, Wenbo; Tian, Guangyan; Zong, Li; Zhou, Yanmin; Kang, Yuru; Wang, Qin; Wang, Aiqin

    2017-01-01

    A series of mesoporous silicate adsorbents with superior adsorption performance for hazardous chlortetracycline (CTC) were sucessfully prepared via a facile one-pot hydrothermal reaction using low-cost illite/smectite (IS) clay, sodium silicate and magnesium sulfate as the starting materials. In this process, IS clay was "teared up" and then "rebuilt" as new porous silicate adsorbent with high specific surface area of 363.52m(2)/g (about 8.7 folds higher than that of IS clay) and very negative Zeta potential (-34.5mV). The inert SiOSi (Mg, Al) bonds in crystal framework of IS were broken to form Si(Al) O(-) groups with good adsorption activity, which greatly increased the adsorption sites served for holding much CTC molecules. Systematic evaluation on adsorption properties reveals the optimal silicate adsorbent can adsorb 408.81mg/g of CTC (only 159.7mg/g for raw IS clay) and remove 99.3% (only 46.5% for raw IS clay) of CTC from 100mg/L initial solution (pH3.51; adsorption temperature 30°C; adsorbent dosage, 3g/L). The adsorption behaviors of CTC onto the adsorbent follows the Langmuir isotherm model, Temkin equation and pseudo second-order kinetic model. The mesopore adsorption, electrostatic attraction and chemical association mainly contribute to the enhanced adsorption properties. As a whole, the high-efficient silicate adsorbent could be candidates to remove CTC from the wastewater with high amounts of CTC. Copyright © 2016. Published by Elsevier B.V.

  5. Treatment of a simulated textile wastewater in a sequencing batch reactor (SBR) with addition of a low-cost adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Sílvia C.R., E-mail: scrs@fe.up.pt; Boaventura, Rui A.R.

    2015-06-30

    Highlights: • Treating textile dyeing effluents by SBR coupled with waste sludge adsorption. • Metal hydroxide sludge: a good adsorbent for a direct textile dye. • Good adsorption capacities were found with the low-cost adsorbent. • Adsorbent performance considerably reduced by auxiliary products. • Color removal complies with discharge limits. - Abstract: Color removal from textile wastewaters, at a low-cost and consistent technology, is even today a challenge. Simultaneous biological treatment and adsorption is a known alternative to the treatment of wastewaters containing biodegradable and non-biodegradable contaminants. The present work aims at evaluating the treatability of a simulated textile wastewater by simultaneously combining biological treatment and adsorption in a SBR (sequencing batch reactor), but using a low-cost adsorbent, instead of a commercial one. The selected adsorbent was a metal hydroxide sludge (WS) from an electroplating industry. Direct Blue 85 dye (DB) was used in the preparation of the synthetic wastewater. Firstly, adsorption kinetics and equilibrium were studied, in respect to many factors (temperature, pH, WS dosage and presence of salts and dyeing auxiliary chemicals in the aqueous media). At 25 °C and pH 4, 7 and 10, maximum DB adsorption capacities in aqueous solution were 600, 339 and 98.7 mg/g, respectively. These values are quite considerable, compared to other reported in literature, but proved to be significantly reduced by the presence of dyeing auxiliary chemicals in the wastewater. The simulated textile wastewater treatment in SBR led to BOD{sub 5} removals of 53–79%, but color removal was rather limited (10–18%). The performance was significantly enhanced by the addition of WS, with BOD{sub 5} removals above 91% and average color removals of 60–69%.

  6. Novel Anionic Clay Adsorbents for Boiler-Blow Down Waters Reclaim and Reuse

    Energy Technology Data Exchange (ETDEWEB)

    Muhammad Sahimi; Theodore T. Tsotsis

    2005-12-01

    Our goal in this study is to utilize novel anionic clay sorbents for treating and reclaiming/reusing power-plant effluents, in particular, boiler blow-down waters containing heavy metals, such as As and Se. Developing and using novel materials for such application is dictated by the challenge posed by reclaiming and recycling these too-clean-to-clean effluent streams, generated during electricity production, whose contaminant levels are in the ppm/ppb (or even less) trace levels. During the study model blow-down streams have been treated in batch experiments. Adsorption isotherms as a function of pH/temperature have been established for both As and Se. Adsorption rates have also measured as a function of concentration, temperature, pH, and space time. For both the equilibrium and rate measurements, we have studied the As/Se interaction, and competition from background anions. A homogeneous surface diffusion model is used to describe the experimental kinetic data. The estimated diffusivity values are shown to depend on the particle size. On the other hand, a model taking into account the polycrystalline nature of these adsorbent particles, and the presence of an intercrystallite porous region predicts correctly that the surface diffusivity is particle size independent. A mathematical model to describe flow experiments in packed-beds has also been developed during phase I of this project. The goal is to validate this model with flow experiments in packed-beds during the phase II of this project, to determine the adsorption capacity under flow conditions, and to compare it with the capacity estimated from the adsorption isotherms determined from the batch studies.

  7. FTIR study of the relation, between extra-framework aluminum species and the adsorbed molecular water, and its effect on the acidity in ZSM-5 steamed zeolite

    Directory of Open Access Journals (Sweden)

    Luis Fioravanti Isernia

    2013-01-01

    Full Text Available The infrared spectroscopy study of zeolite samples, obtained by steam treatment at 560‑960 °C of the ZSM‑5 catalyst (framework Si/Al ratio of 13, suggests an association between adsorbed molecular water and extra‑framework aluminum hydroxyls generated after treatment. Moreover, infrared spectroscopy of adsorbed pyridine shows the reduction of the densities of Brönsted and Lewis sites, when treatment temperature rises, with contradicts the frequently accepted mechanism of the transformation of two bridged Si‑OH‑Al groups for each Lewis site generated. The gradual conversion of the octahedral extra-framework aluminum (Lewis‑associated in polymeric species with low acidity is the most probable cause of this behavior. On the other hand, the apparent decline of the acid Brönsted strength, with the increase in the temperature of the hydrothermal treatment, has two possible causes: a the decreasing accessibility, of the pyridine molecular probe to bridged Si-OH-Al groups with the strongest Brönsted acidity, inside the channels, and b the gradual transformation of these groups into extra framework species of weak acidity.

  8. FTIR study of the relation between extra-framework aluminum species and the adsorbed molecular water, and its effect on the acidity in ZSM-5 steamed zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Isernia, Luis Fioravanti, E-mail: luis.isernia@gmail.com [Laboratorio de Tamices Moleculares, Universidad de Oriente - UO, Maturin, Monagas (Venezuela, Bolivarian Republic of)

    2013-11-01

    The infrared spectroscopy study of zeolite samples, obtained by steam treatment at 560-960 Degree-Sign C of the ZSM-5 catalyst (framework Si/Al ratio of 13), suggests an association between adsorbed molecular water and extra-framework aluminum hydroxyls generated after treatment. Moreover, infrared spectroscopy of adsorbed pyridine shows the reduction of the densities of Broensted and Lewis sites, when treatment temperature rises, with contradicts the frequently accepted mechanism of the transformation of two bridged Si-OH-Al groups for each Lewis site generated. The gradual conversion of the octahedral extra-framework aluminum (Lewis-associated) in polymeric species with low acidity is the most probable cause of this behavior. On the other hand, the apparent decline of the acid Broensted strength, with the increase in the temperature of the hydrothermal treatment, has two possible causes: a) the decreasing accessibility, of the pyridine molecular probe to bridged Si-OH-Al groups with the strongest Broensted acidity, inside the channels, and b) the gradual transformation of these groups into extra framework species of weak acidity. (author)

  9. Immobilized Tannin from Sanseviera trifasciata on Carbon as Adsorbent For Iron(II in Polluted Water Source

    Directory of Open Access Journals (Sweden)

    Irfan Hanafi Arif

    2016-03-01

    Full Text Available The organic-agricultural waste resulted from local farmer or community gardening recently paid public attention. The presence and easily grown of “Lidah Mertua” or Sanseviera trifasciata being focused on potency investigation for its prospecting application. It was reported contain some phenolic and also tannin extracted from aqueous solvents. This paper revealed recent investigation applying of its isolated tannin from leave part to modifying of activated carbon. The previous report published that carbon were able to adsorb some toxic heavy metals. However, it has some limitation including lower capacity adsorption. Impregnated or immobilized the tannin-isolated from S. trifasciata leaves was able to modify the carbon functionality, physical appearance, pores size, and it adsorption capacity. Both Langmuir and Freundlich adsorption mechanism model also disclosed the developed adsorbent mechanism of iron(II adsorption on the adsorbent tannin-immobolized on carbon. The real test using community well drilling water source also gave important finding on the concentration of iron(II contained on water source.

  10. Iron oxide inside SBA-15 modified with amino groups as reusable adsorbent for highly efficient removal of glyphosate from water

    Science.gov (United States)

    Fiorilli, Sonia; Rivoira, Luca; Calì, Giada; Appendini, Marta; Bruzzoniti, Maria Concetta; Coïsson, Marco; Onida, Barbara

    2017-07-01

    Iron oxide clusters were incorporated into amino-functionalized SBA-15 in order to obtain a magnetically recoverable adsorbent. The physical-chemical properties of the material were characterized by FE-SEM, STEM, XRD, TGA, XPS, FT-IR and acid-base titration analysis. Iron oxide nanoparticles were uniformly dispersed into the pore of mesoporous silica and that the adsorbent is characterized high specific surface area (177 m2/g) and accessible porosity. The sorbent was successfully tested for the removal of glyphosate in real water matrices. Despite the significant content of inorganic ions, a quantitative removal of the contaminant was found. The complete regeneration of the sorbent after the adsorption process through diluted NaOH solution was also proved.

  11. Gas-Solid Reaction Properties of Fluorine Compounds and Solid Adsorbents for Off-Gas Treatment from Semiconductor Facility

    Directory of Open Access Journals (Sweden)

    Shinji Yasui

    2012-01-01

    Full Text Available We have been developing a new dry-type off-gas treatment system for recycling fluorine from perfluoro compounds present in off-gases from the semiconductor industry. The feature of this system is to adsorb the fluorine compounds in the exhaust gases from the decomposition furnace by using two types of solid adsorbents: the calcium carbonate in the upper layer adsorbs HF and converts it to CaF2, and the sodium bicarbonate in the lower layer adsorbs HF and SiF4 and converts them to Na2SiF6. This paper describes the fluorine compound adsorption properties of both the solid adsorbents—calcium carbonate and the sodium compound—for the optimal design of the fixation furnace. An analysis of the gas-solid reaction rate was performed from the experimental results of the breakthrough curve by using a fixed-bed reaction model, and the reaction rate constants and adsorption capacity were obtained for achieving an optimal process design.

  12. Water treatment: Chitosan associated with electrochemical methods

    Science.gov (United States)

    Tamiasso-Martinhon, Priscila; Marques Teixeira de Souza, João; Cruzeiro da Silva, Silvia Maria; Pellegrini Pessoa, Fernando Luiz; Sousa, Célia

    2017-04-01

    Pollution of water bodies due to the presence of toxic metals and organic compounds, bring out a series of environmental problems of public, government and social character. In addition, water pollution, has become the target and source of concern in many industrial sectors. Therefore, it is essential to develop technologies for treatment and purification of water. Chitosan is a natural product derived from chitin, extracted mainly from the shells of crustaceans. It is a low cost, renewable and biodegradable biopolymer of great socioeconomic and environmental importance. The classic treatment of wastewater containing metals involves physical chemistry processes of precipitation, ion exchange and electrochemistry. Electrochemical technology has been presented as the most promising methods for treating wastewater polluted with metals, colloids, dyes or oil in water emulsions; besides being used in removing organic compounds. Alternative methods like adsorption with biosorbents have been investigated. The great advantage of this latter over other techniques is the low generation of residues, easy recovery of metals and the possibility of reuse of the adsorbent. This article aimed to carry out an exploratory study, of bibliographical nature, on the use of chitosan in electrochemical methods for water treatment.

  13. Specifications for coke fines as potential adsorbents for coking plant waste water

    Energy Technology Data Exchange (ETDEWEB)

    Karcz, A.; Czepirska-Komorowska, E.; Burmistrz, P. (Akademia Gorniczo-Hutnicza, Cracow (Poland). Wydzial Energochemii Wegla i Fizykochemii Sorbentow)

    1993-01-01

    Proposes utilization of coke dust from coke dry quenching and from dedusting facilities for the purification of coking plant waste water. A process flowsheet is presented for waste water treatment at the Przyjazn coking plant, the only Polish coking plant employing coke dry quenching. The proposal for coke dust use is explained; properties of 4 types of coke dust available at the plant are compared to those of Carbopol Z-4 activated carbon. Adsorption isotherms were determined for the coke dust, as well as pore structures and pore size distribution. A high share of micropores was found in Carbopol Z-4, while coke dust had a higher amount of mesopores. Substantial differences were expected in adsorption performance of dusts compared to activated carbon, but this was not confirmed in laboratory purification of waste water. 19 refs.

  14. The Determination of Mobility and Immobility of Water Adsorbed in Type 5A and 13X Zeolites by IR and DTA

    National Research Council Canada - National Science Library

    F. Ucun

    2002-01-01

    In this study, infrared (IR) and differential thermal analysis (DTA) data were used to investigate the mobility of water adsorbed in synthetic zeolites of type 5A and 13X with pore diameters of 5 and 10 Å, respectively...

  15. Mesocarbon Microbead Carbon-Supported Magnesium Hydroxide Nanoparticles: Turning Spent Li-ion Battery Anode into a Highly Efficient Phosphate Adsorbent for Wastewater Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yan; Guo, Xingming; Wu, Feng; Yao, Ying; Yuan, Yifei; Bi, Xuanxuan; Luo, Xiangyi; Shahbazian-Yassar, Reza; Zhang, Cunzhong; Amine, Khalil

    2016-08-24

    Phosphorus in water eutrophication has become a serious problem threatening the environment. However, the development of efficient adsorbents for phosphate removal from water is lagging. In this work, we recovered the waste material, graphitized carbon, from spent lithium ion batteries and modified it with nanostructured Mg(OH)2 on the surface to treat excess phosphate. This phosphate adsorbent shows one of the highest phosphate adsorption capacities to date, 588.4 mg/g (1 order of magnitude higher than previously reported carbon-based adsorbents), and exhibits decent stability. A heterogeneous multilayer adsorption mechanism was proposed on the basis of multiple adsorption results. This highly efficient adsorbent from spent Li-ion batteries displays great potential to be utilized in industry, and the mechanism study paved a way for further design of the adsorbent for phosphate adsorption.

  16. Mesocarbon Microbead Carbon-Supported Magnesium Hydroxide Nanoparticles: Turning Spent Li-ion Battery Anode into a Highly Efficient Phosphate Adsorbent for Wastewater Treatment.

    Science.gov (United States)

    Zhang, Yan; Guo, Xingming; Wu, Feng; Yao, Ying; Yuan, Yifei; Bi, Xuanxuan; Luo, Xiangyi; Shahbazian-Yassar, Reza; Zhang, Cunzhong; Amine, Khalil

    2016-08-24

    Phosphorus in water eutrophication has become a serious problem threatening the environment. However, the development of efficient adsorbents for phosphate removal from water is lagging. In this work, we recovered the waste material, graphitized carbon, from spent lithium ion batteries and modified it with nanostructured Mg(OH)2 on the surface to treat excess phosphate. This phosphate adsorbent shows one of the highest phosphate adsorption capacities to date, 588.4 mg/g (1 order of magnitude higher than previously reported carbon-based adsorbents), and exhibits decent stability. A heterogeneous multilayer adsorption mechanism was proposed on the basis of multiple adsorption results. This highly efficient adsorbent from spent Li-ion batteries displays great potential to be utilized in industry, and the mechanism study paved a way for further design of the adsorbent for phosphate adsorption.

  17. Zirconium-based metal organic frameworks: Highly selective adsorbents for removal of phosphate from water and urine

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Kun-Yi Andrew, E-mail: linky@nchu.edu.tw [Department of Environmental Engineering, National Chung Hsing University, 250 Kuo-Kuang Road, Taichung, Taiwan (China); Chen, Shen-Yi [Department of Environmental Engineering, National Chung Hsing University, 250 Kuo-Kuang Road, Taichung, Taiwan (China); Jochems, Andrew P. [New Mexico Bureau of Geology & Mineral Resources and New Mexico Institute of Mining & Technology, Socorro, NM (United States)

    2015-06-15

    Phosphate is one of the most concerning compounds in wastewater streams and a main nutrient that causes eutrophication. To eliminate the phosphate pollution, Metal Organic Frameworks (MOFs) are proposed in this study as adsorbents to remove phosphate from water. The zirconium-based MOF, UiO-66, was selected as representative MOF given its exceptional stability in water. To investigate the effect of an amine functional group, UiO-66-NH2 was also prepared using an amine-substituted ligand. The adsorption kinetics and isotherm reveal that UiO-66-NH2 exhibited higher adsorption capacities than UiO-66 possibly due to the amine group. However, the interaction between phosphate and zirconium sites of UiO MOFs might be the primary factor accounting for the phosphate adsorption to UiO MOFs. UiO MOFs also exhibited a high selectivity towards phosphate over other anions such as bromate, nitrite and nitrate. Furthermore, UiO MOFs were found to adsorb phosphate and to completely remove diluted phosphate in urine. We also found that UiO MOFs could be easily regenerated and re-used for phosphate adsorption. These findings suggest that UiO MOFs can be effective and selective adsorbents to remove phosphate from water as well as urine. - Highlights: • UiO-66 as the first type of MOFs was used to remove phosphate from water and urine. • The amine group in UiO MOFs was found to enhance the phosphate adsorption. • UiO-66 exhibited a high adsorption selectivity towards phosphate over other anions. • UiO-66 could be easily regenerated and re-used with 85% regeneration efficiency.

  18. Degradation of aldrin in adsorbed system using advanced oxidation processes: comparison of the treatment methods.

    Science.gov (United States)

    Kusvuran, Erdal; Erbatur, Oktay

    2004-01-30

    In this study, Fenton, UV/Fenton, UV/H2O2, UV/Fe2+ advanced oxidation processes have been applied for degradation of aldrin adsorbed on Na-montmorillonitte and activated carbon. Aldrin adsorbed on Na-montmorillonitte was degraded more efficiently than that of on activated carbon. For example, in UV/Fenton technique 95% of aldrin was removed from Na-montmorillonitte while 50% degradation was observed on activated carbon. Degradation of aldrin adsorbed on Na-montmorillonitte has also been achieved effectively using UV/Fe2+ technique despite the absence of H2O2. All AOPs but Fenton have been observed nearly equally effective for degradation of aldrin on Na-montmorillonitte sorbent. Fenton reaction exhibited least activity in degradation aldrin adsorbed on Na-montmorillonitte. The experiments with activated carbon sorbent indicated that phenyl groups in activated carbon structure and aldrin molecules exhibited competitive behavior on reaction with OH* radicals. The results of infrared spectroscopy support this assumption. The degradation efficiency of aldrin using activated carbon sorbent was determined in the following order: UV/Fenton > UV/H2O2 > Fenton > UV/Fe2+. Copyright 2003 Elsevier B.V.

  19. Host and adsorbate dynamics in silicates with flexible frameworks: Empirical force field simulation of water in silicalite

    Science.gov (United States)

    Bordat, Patrice; Cazade, Pierre-André; Baraille, Isabelle; Brown, Ross

    2010-03-01

    Molecular dynamics simulations are performed on the pure silica zeolite silicalite (MFI framework code), maintaining via a new force field both framework flexibility and realistic account of electrostatic interactions with adsorbed water. The force field is similar to the well-known "BKS" model [B. W. H. van Beest et al., Phys. Rev. Lett. 64, 1955 (1990)], but with reduced partial atomic charges and reoptimized covalent bond potential wells. The present force field reproduces the monoclinic to orthorhombic transition of silicalite. The force field correctly represents the hydrophobicity of pure silica silicalite, both the adsorption energy, and the molecular diffusion constants of water. Two types of adsorption, specific and weak unspecific, are predicted on the channel walls and at the channel intersection. We discuss molecular diffusion of water in silicalite, deducing a barrier to crossing between the straight and the zigzag channels. Analysis of the thermal motion shows that at room temperature, framework oxygen atoms incurring into the zeolite channels significantly influence the dynamics of adsorbed water.

  20. Simultaneous removal of multiple pesticides from water: effect of organically modified clays as coagulant aid and adsorbent in coagulation-flocculation process.

    Science.gov (United States)

    Shabeer, T P Ahammed; Saha, Ajoy; Gajbhiye, V T; Gupta, Suman; Manjaiah, K M; Varghese, Eldho

    2014-01-01

    Contamination of drinking water sources with agrochemical residues became a major concern in the twenty-first century. Coagulation-flocculation is the most widely used water-treatment process, but the efficiency to remove pesticides and other organic pollutants are limited compared to adsorption process. Thus, simultaneous action of adsorption on normal bentonite or organo-modified montmorillonite clays [modified with octadecylamine (ODA-M) and octadecylamine + amino-propyltriethoxysilane (ODAAPS-M)] followed by coagulation-flocculation by alum and poly aluminium chloride has been evaluated for removal of 10 different pesticides, namely atrazine, lindane, metribuzin, aldrin, chlorpyriphos, pendimethalin, alpha-endosulphan, beta-endosulphan, p,p'-DDT, cypermethrin and two of its metabolites, endosulphan sulphate and p,p'-DDE, from water. The coagulation without integration of adsorption was less effective (removal % varies from 12 to 49) than the adsorption-coagulation integrated system (removal % varies from 71 to 100). Further, coagulation integrated with adsorption was more effective when organically modified montmorillonite was used as adsorbent compared to normal bentonite. The removal efficiency of organic clay depends upon the concentration of pesticides, doses of clay minerals, and efficiency was more for ODAAPS-M as compared to ODA-M. The combination of ODAAPS-M-clay with coagulants was also used efficiently for the removal of pesticides from natural and fortified natural water collected and the results exhibit the usefulness of this remediation technique for application in water decontamination and in treatment of industrial and agricultural waste waters.

  1. Potassium Niobate Nanolamina: A Promising Adsorbent for Entrapment of Radioactive Cations from Water

    Science.gov (United States)

    Sun, Jin; Yang, Dongjiang; Sun, Cuihua; Liu, Long; Yang, Shuanglei; (Alec) Jia, Yi; Cai, Rongsheng; Yao, Xiangdong

    2014-12-01

    Processing and managing radioactive waste is a great challenge worldwide as it is extremely difficult and costly; the radioactive species, cations or anions, leaked into the environment are a serious threat to the health of present and future generations. We report layered potassium niobate (K4Nb6O17) nanolamina as adsorbent to remove toxic Sr2+, Ba2+ and Cs+ cations from wastewater. The results show that K4Nb6O17 nanolamina can permanently confine the toxic cations within the interlayer spacing via a considerable deformation of the metastable layered structure during the ion exchange process. At the same time, the nanolaminar adsorbent exhibits prompt adsorption kinetics, high adsorption capacity and selectivity, and superior acid resistance. These merits make it be a promising material as ion exchanger for the removal of radioactive cations from wastewater.

  2. Calcium hydroxide as low cost adsorbent for the effective removal of indigo carmine dye in water

    Directory of Open Access Journals (Sweden)

    Thimmasandra Narayan Ramesh

    2017-02-01

    Full Text Available Adsorption of indigo carmine dye onto calcium hydroxide was investigated in this work. The variation in the pH, adsorbent dose, dye concentration, duration and the temperature was evaluated. Adsorption of indigo carmine dye onto calcium hydroxide was effective at pH 12 (50 min and follows Langmuir-type isotherm behaviour. The adsorption process follows pseudo-second order rate kinetics. Enthalpy, entropy, free energy and the activation energy parameters have been reported.

  3. Calcium hydroxide as low cost adsorbent for the effective removal of indigo carmine dye in water

    OpenAIRE

    Thimmasandra Narayan Ramesh; Devarahosahally Veeranna Kirana; Ashwathaiah Ashwini; T.R. Manasa

    2017-01-01

    Adsorption of indigo carmine dye onto calcium hydroxide was investigated in this work. The variation in the pH, adsorbent dose, dye concentration, duration and the temperature was evaluated. Adsorption of indigo carmine dye onto calcium hydroxide was effective at pH 12 (50 min) and follows Langmuir-type isotherm behaviour. The adsorption process follows pseudo-second order rate kinetics. Enthalpy, entropy, free energy and the activation energy parameters have been reported.

  4. Novel Adsorbent-Reactants for Treatment of Ash and Scrubber Pond Effluents

    Energy Technology Data Exchange (ETDEWEB)

    Bill Batchelor; Dong Suk Han; Eun Jung Kim

    2010-01-31

    The overall goal of this project was to evaluate the ability of novel adsorbent/reactants to remove specific toxic target chemicals from ash and scrubber pond effluents while producing stable residuals for ultimate disposal. The target chemicals studied were arsenic (As(III) and As(V)), mercury (Hg(II)) and selenium (Se(IV) and Se(VI)). The adsorbent/reactants that were evaluated are iron sulfide (FeS) and pyrite (FeS{sub 2}). Procedures for measuring concentrations of target compounds and characterizing the surfaces of adsorbent-reactants were developed. Effects of contact time, pH (7, 8, 9, 10) and sulfate concentration (0, 1, 10 mM) on removal of all target compounds on both adsorbent-reactants were determined. Stability tests were conducted to evaluate the extent to which target compounds were released from the adsorbent-reactants when pH changed. Surface characterization was conducted with x-ray photoelectron spectroscopy (XPS) to identify reactions occurring on the surface between the target compounds and surface iron and sulfur. Results indicated that target compounds could be removed by FeS{sub 2} and FeS and that removal was affected by time, pH and surface reactions. Stability of residuals was generally good and appeared to be affected by the extent of surface reactions. Synthesized pyrite and mackinawite appear to have the required characteristics for removing the target compounds from wastewaters from ash ponds and scrubber ponds and producing stable residuals.

  5. Ferrocene functionalized nanoscale mixed-oxides as a potent phosphate adsorbent from the synthetic and real (Persian Gulf) waters.

    Science.gov (United States)

    Arshadi, M; Zandi, H; Akbari, J; Shameli, A

    2015-07-15

    The application of covalently attached ferrocene groups to the aluminum-silicate nanoparticles (ASNPs) for phosphate (P) removal from the synthetic and real waters has been studied and the prepared nanomaterials were analyzed by XPS, EDS, BET, TEM, chemical analysis (CHN), FTIR, and ICP-AES. The immobilization of the ferrocene on the surface of the inorganic support (mixed oxides) can lead to reduce the drawback of the pristine ferrocene molecules which may have strong tendency to agglomerate into larger particles, resulting in the negative effect on both available active sites and catalyst performance. XPS of Fe ions evidenced that most of the active sites of the nano-adsorbent is in the form of Fe(III) ions at the surface. The heterogeneous Fe(III) ions were effective toward removal of phosphate. The contact time to obtain equilibrium for maximum adsorption of phosphate (100%) was found to be 120 min. The adsorption kinetics of P has been evaluated in terms of pseudo-first- and -second-order kinetics, and the Freundlich and Langmuir isotherm models have also been tested to the equilibrium adsorption results. The adsorption process was spontaneous and endothermic in nature and followed pseudo-second-order kinetic model. FTIR, EDS and XPS results confirmed the formation of Fe-O-P bond on the Si/Al@Fe surface after adsorption of P from aqueous media. The Si/Al@Fe displayed high reusability due to its high removal capacity after 10th adsorption-desorption runs. The proposed adsorbent could also be utilized to adsorb the P ions from the real sample (Persian Gulf water). The high removal capacity of P ions from the real water and the high levels of reusability confirmed the versatility of the heterogenized ferrocene groups on the ASNPs. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Development of Composite Adsorbents for LLW Treatment and Their Adsorption Properties for Cs and Sr - 13127

    Energy Technology Data Exchange (ETDEWEB)

    Susa, Shunsuke; Mimura, Hitoshi [Dept. of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Aramaki-Aza-Aoba 6-6-01-2, Sendai, 980-8579 (Japan); Ito, Yoshiyuki; Saito, Yasuo [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, 2-4 Shirakata Shirone, Naka-gun, Ibaraki, 319-1195 (Japan)

    2013-07-01

    In this study, the composite adsorbents (KCoFC-NM (NM: natural mordenite), KCoFC-SG (SG: porous silica gel), AMP-SG and so on) were prepared by impregnation-precipitation methods. As for the distribution properties, the largest K{sub d,Cs} value of 3.8 x 10{sup 4} cm{sup 3}/g was obtained for KCoFC-SG (Davi.) composite. KCoFC-SG (NH, MB5D) and T-KCFC also had relatively large K{sub d,Cs} values above 1.0 x 10{sup 4} cm{sup 3}/g. The uptake rate of Cs{sup +} ions was examined by batch method. KCoFC-SG (NH, MB5D) and AMP-SG (Davi.) had relatively large uptake rate of Cs{sup +}, and the uptake attained equilibrium within 1 h. The maximum uptake capacity of Cs{sup +} ions was estimated to be above 0.5 mmol/g for KCoFC-NM and KCoFC-CP composites. KCoFC-X composite had a relatively large uptake capacity of Cs{sup +} ions (0.23 mmol/g > 0.17 mmol/g (T-KCFC)) and this composite also had a selectivity towards Sr{sup 2+} ions; KCoFC-X is effective adsorbent for both Cs{sup +} and Sr{sup 2+} ions. The largest value of K{sub d,Sr} was estimated to be 218 cm{sup 3}/g for titanic acid-PAN. Titanic acid-PAN had the largest uptake rate of Sr{sup 2+} ions, and the uptake attained equilibrium within 8 h. Adsorbability of other nuclides was further examined by batch method. All adsorbents had adsorbability for Rb{sup +} and RuNO{sup 3+} ions. KCoFC-SG (NH), KCoFC-CP and T-KCFC had higher selectivity towards Cs{sup +} than other adsorbents; these adsorbents had adsorbability to Cs{sup +} ions even in the presence of Ba{sup 2+}, Ca{sup 2+} and Mg{sup 2+} ions. The separation factor of K{sub d,Sr}/K{sub d,Ba} for titanic acid-PAN was about 1, indicating that the K{sub d,Sr} for titanic acid-PAN tends to decrease with Ba{sup 2+} concentration. As for the breakthrough properties, the largest 5 % breakpoint and 5 % breakthrough capacity of Cs{sup +} ions were estimated to be 47.1 cm{sup 3} and 0.07 mmol/g for the column of KCoFC-SG (NH), respectively. The order of 5 % breakthrough capacity

  7. Why can water cages adsorb aqueous methane? A potential of mean force calculation on hydrate nucleation mechanisms.

    Science.gov (United States)

    Guo, Guang-Jun; Li, Meng; Zhang, Yi-Gang; Wu, Chang-Hua

    2009-11-28

    By performing constrained molecular dynamics simulations in the methane-water system, we successfully calculated the potential of mean force (PMF) between a dodecahedral water cage (DWC) and dissolved methane for the first time. As a function of the distance between DWC and methane, this is characterized by a deep well at approximately 6.2 A and a shallow well at approximately 10.2 A, separated by a potential barrier at approximately 8.8 A. We investigated how the guest molecule, cage rigidity and the cage orientation affected the PMF. The most important finding is that the DWC itself strongly adsorbs methane and the adsorption interaction is independent of the guests. Moreover, the activation energy of the DWC adsorbing methane is comparable to that of hydrogen bonds, despite differing by a factor of approximately 10% when considering different water-methane interaction potentials. We explain that the cage-methane adsorption interaction is a special case of the hydrophobic interaction between methane molecules. The strong net attraction in the DWC shell with radii between 6.2 and 8.8 A may act as the inherent driving force that controls hydrate formation. A cage adsorption hypothesis for hydrate nucleation is thus proposed and discussed.

  8. Removal of fluoride from drinking water using a modified fly ash adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Debasis Goswami; Arabinda K. Das

    2006-01-15

    Fly ash from a coal-fired power station was chemically modified and utilized for the removal of fluoride from drinking water. Two types of beds were used. Bed I was prepared by treatment with 12M HCl followed by neutralization with 5M NaOH solution. The reaction mass was filtered, washed, dried, and crushed to fine powder. Bed I material was mixed with alum and MgCl{sub 2} solutions and treated with 0.9M Na{sub 2}CO{sub 3} until pH reached to 4.5. Mass was again filtered, washed, dried at 120{sup o}C for 4 h and crushed to fine powder. This bed material is Bed II, which was used for defluoridation. Bed I was used to maintain pH (7.5-8.5) of the final effluent. Fluoride (100 ppm) present in both synthetic mixtures and drinking water samples was allowed to pass through Bed II (15 g) absorbent and effluents were found to contain no fluoride but pH of the effluent was 5.4-5.5. To maintain WHO guidelines for drinking water on pH, this effluent was again passed through Bed I. The effectiveness of the modified fly ash bed was satisfactory.

  9. Potassium Niobate Nanolamina: A Promising Adsorbent for Entrapment of Radioactive Cations from Water

    OpenAIRE

    Sun, Jin; Yang, Dongjiang; Sun, Cuihua; Liu, Long; Yang, Shuanglei; Jia, Yi; Cai, Rongsheng; Yao, Xiangdong

    2014-01-01

    Processing and managing radioactive waste is a great challenge worldwide as it is extremely difficult and costly; the radioactive species, cations or anions, leaked into the environment are a serious threat to the health of present and future generations. We report layered potassium niobate (K4Nb6O17) nanolamina as adsorbent to remove toxic Sr2+, Ba2+ and Cs+ cations from wastewater. The results show that K4Nb6O17 nanolamina can permanently confine the toxic cations within the interlayer spac...

  10. Inhibition of Lipid Oxidation in Oil-in-Water Emulsions by Interface-Adsorbed Myofibrillar Protein.

    Science.gov (United States)

    Yang, Jiayi; Xiong, Youling L

    2015-10-14

    This study investigated the role of interfacial myofibrillar protein (MFP) in the oxidative stabilization of meat emulsions. Emulsions with 10% oil were prepared using either 2% (w/v) Tween 20 or 0.25, 0.5, and 1% (w/v) MFP and then subjected to hydroxyl radical oxidation at 4 °C for 0, 2, and 24 h. MFP was more readily oxidized (intrinsic fluorescence quenching, sulfur losses, and carbonyl formation) than oil [conjugated dienes and 2-thiobarbituric acid-reactive substances (TBARS)]. However, oxidized MFP in the continuous phase stimulated lipid oxidation after 24 h, sharply contrasting with interface-adsorbed MFP that inhibited TBARS formation nearly 90% (p oxidized samples exhibited greater losses of fluorescence and more extensive polymerization of myosin (detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis) than MFP present in the continuous phase. Results indicated that, due to the physical localization, interface-adsorbed MFP in general and myosin in particular provided accentuated protection of emulsions against oxidation.

  11. Optimization of tetravalent manganese feroxyhyte's negative charge density: A high-performing mercury adsorbent from drinking water.

    Science.gov (United States)

    Kokkinos, E; Simeonidis, K; Pinakidou, F; Katsikini, M; Mitrakas, M

    2017-01-01

    This study demonstrates an optimization procedure for the development of an Hg-specified adsorbent able to comply with the regulation limit for drinking water of 1μg/L. On this purpose, the synthesis of Mn(IV)-feroxyhyte was modified to achieve high negative charge density by combining alkaline and extreme oxidizing conditions. In particular, precipitation of FeSO4 at pH9 and excess of KMnO4 follows a very fast nucleation step providing a product with very small nanocrystal size (1-2nm), high specific surface area (300m(2)/g) and maximum negative charge density (1.8mmol H(+)/g). The adsorbent was validated for Hg removal in batch experiments and column tests using natural-like water indicating an adsorption capacity as high as 2.5μg/mg at equilibrium concentration 1μg/L under reliable conditions of application. Importantly, the adsorption is an exothermic spontaneous process, resulting in the formation of inner sphere complexes by sharing both A-type and B-type oxygen atoms with the metal surface octahedral as revealed by the X-ray absorption fine structure results. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Comparison between nitrate and pesticide removal from ground water using adsorbents and NF and RO membranes.

    Science.gov (United States)

    Tepus, Brigita; Simonic, Marjana; Petrinić, Irena

    2009-10-30

    An investigation was carried out regarding the removal of pollutants such as nitrate and pesticides (atrazine, deethylatrazine and deisopropylatrazine) from actual ground water samples obtained in Slovenia, by the use of two new adsorption resins, one derived from styrenedivinylbenzene and one from polystyrene, and commercial nanofiltration and reverse osmosis membranes. Atrazine and deethylatrazine were also bound to the activated carbon. Despite the different technologies applied, the effort was directed towards simultaneous removal of the above-mentioned pollutants. According to the results, the first of the mentioned adsorption resins was successfully used for pesticides' removal among the tested adsorption media, whereas the removal of nitrates was unsuccessful. The reverse osmosis membrane displayed a high rejection of all compounds. All concentration values after treatment were below the maximum concentration allowed, while the nanofiltration membrane showed lower compound rejection, thus being suitable for atrazine removal.

  13. Treatment of a simulated textile wastewater in a sequencing batch reactor (SBR) with addition of a low-cost adsorbent.

    Science.gov (United States)

    Santos, Sílvia C R; Boaventura, Rui A R

    2015-06-30

    Color removal from textile wastewaters, at a low-cost and consistent technology, is even today a challenge. Simultaneous biological treatment and adsorption is a known alternative to the treatment of wastewaters containing biodegradable and non-biodegradable contaminants. The present work aims at evaluating the treatability of a simulated textile wastewater by simultaneously combining biological treatment and adsorption in a SBR (sequencing batch reactor), but using a low-cost adsorbent, instead of a commercial one. The selected adsorbent was a metal hydroxide sludge (WS) from an electroplating industry. Direct Blue 85 dye (DB) was used in the preparation of the synthetic wastewater. Firstly, adsorption kinetics and equilibrium were studied, in respect to many factors (temperature, pH, WS dosage and presence of salts and dyeing auxiliary chemicals in the aqueous media). At 25 °C and pH 4, 7 and 10, maximum DB adsorption capacities in aqueous solution were 600, 339 and 98.7 mg/g, respectively. These values are quite considerable, compared to other reported in literature, but proved to be significantly reduced by the presence of dyeing auxiliary chemicals in the wastewater. The simulated textile wastewater treatment in SBR led to BOD5 removals of 53-79%, but color removal was rather limited (10-18%). The performance was significantly enhanced by the addition of WS, with BOD5 removals above 91% and average color removals of 60-69%. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Water treatment method

    Science.gov (United States)

    Martin, Frank S.; Silver, Gary L.

    1991-04-30

    A method for reducing the concentration of any undesirable metals dissolved in contaminated water, such as waste water. The method involves uniformly reacting the contaminated water with an excess amount of solid particulate calcium sulfite to insolubilize the undesirable metal ions, followed by removal thereof and of the unreacted calcium sulfite.

  15. Silica-based materials as drug adsorbents: first principle investigation on the role of water microsolvation on Ibuprofen adsorption.

    Science.gov (United States)

    Delle Piane, Massimo; Vaccari, Stefano; Corno, Marta; Ugliengo, Piero

    2014-08-07

    Silica-based materials find applications as excipients and, particularly for those of mesoporous nature, as drug delivery agents for pharmaceutical formulations. Their performance can be crucially affected by water moisture, as it can modify the behavior of these formulations, by limiting their shelf life. Here we describe the role of water microsolvation on the features of ibuprofen adsorbed on a model of amorphous silica surface by means of density functional theory (DFT) simulations. Starting from the results of the simulation of ibuprofen in interaction with a dry hydrophobic amorphous silica surface, a limited number of water molecules has been added to study the configurational landscape of the microsolvated system. Structural and energetics properties, as well as the role of dispersive forces, have been investigated. Our simulations have revealed that the silica surface exhibits a higher affinity for water than for ibuprofen, even if several structures coexist at room temperature, with an active competition of ibuprofen and water for the exposed surface silanols. Dispersive interactions play a key role in this system, as pure DFT fails to correctly describe its potential energy surface. Indeed, van der Waals forces are the leading contribution to adsorption, independently of whether the drug is hydrogen-bonded directly to the surface or via water molecules.

  16. Ceiba Pentradenta wood waste activated carbon for waste water treatment

    Directory of Open Access Journals (Sweden)

    K. Geetha

    2014-03-01

    Full Text Available Adsorption is considered to be one of the most promising techniques for waste water treatment over the last decades. The low materials originated from various sources such as agricultural sources and byproducts, agricultural residues and wastes, low-cost sources from which most complex adsorbents will be produced .The farming waste material has to be disposed either safely or must be reused for some valuable purpose. In this consent Ceiba Pentradenta Wood waste, an agricultural waste material which is being converted as Activated carbon in presence of Nitrogen atmosphere at 7000 C is used as an adsorbent for dye removal. The portrayal studies such as bulk density, moisture content, ash content, fixed carbon content, soluble matter (water, acid, matter soluble in acid, pH, decolourising power, ion exchange capacity, percentage content and surface area have been carried out to assess the suitability of these carbons as absorbents in treatment of the water and wastewater. The present study reveals the recovery of valuable adsorbents from readily and cheaply available agriculture wastes.

  17. NMR Study of Spin-Lattice Relaxation of Water Protons by Mn 2+Adsorbed onto Colloidal Silica

    Science.gov (United States)

    Roose, P.; Van Craen, J.; Andriessens, G.; Eisendrath, H.

    The magnetic-field dependence of the water-proton spin-lattice relaxation time (referred to as nuclear-magnetic-relaxation dispersion) has been measured in colloidal silica suspensions after addition of calibrated MnCl 2solutions. The NMRD curves always show the diamagnetic dispersion normally observed in a paramagnetic ion-free silica sol but, above pH 7, also reveal a supplementary relaxation peak at high magnetic fields typical for paramagnetic ion complexes adsorbed onto the silica. The paramagnetic contribution increases linearly with ion concentration until a contribution attributed to free Mn 2+aquo-ions is observed as well. The ion adsorption density[formula]is temperature and pH sensitive; e.g., no adsorption is observed at pH 2.4. The paramagnetic contribution to the experimental NMRD curves, due to adsorption of Mn 2+aquo complexes onto the silica, is satisfactorily described by the Solomon-Bloembergen-Morgan equations. The estimated parameters, resulting from least-squares comparisons, are consistent with the assumption that the primary hydration shell of the adsorbed ion is retained.

  18. Artificial neural network modeling in competitive adsorption of phenol and resorcinol from water environment using some carbonaceous adsorbents.

    Science.gov (United States)

    Aghav, R M; Kumar, Sunil; Mukherjee, S N

    2011-04-15

    This paper illustrates the application of artificial neural network (ANN) for prediction of performances in competitive adsorption of phenol and resorcinol from aqueous solution by conventional and low cost carbonaceous adsorbent materials, such as activated carbon (AC), wood charcoal (WC) and rice husk ash (RHA). The three layer's feed forward neural network with back propagation algorithm in MATLAB environment was used for estimation of removal efficiencies of phenol and resorcinol in bi-solute water environment based on 29 sets of laboratory batch study results. The input parameters used for training of the neural network include amount of adsorbent (g/L), initial concentrations of phenol (mg/L) and resorcinol (mg/L), contact time (h), and pH. The removal efficiencies of phenol and resorcinol were considered as an output of the neural network. The performances of the developed ANN models were also measured using statistical parameters, such as mean error, mean square error, root mean square error, and linear regression. The comparison of the removal efficiencies of pollutants using ANN model and experimental results showed that ANN modeling in competitive adsorption of phenolic compounds reasonably corroborated with the experimental results. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. REMOVAL OF FLUORIDE FROM DRINKING WATER BY COCONUT HUSK AS NATURAL ADSORBENT

    OpenAIRE

    Islamuddin*, Rajneesh k Gautam, Shaista Fatima

    2016-01-01

    High fluoride concentration is a worldwide problem in drinking water due its health effects. In India large population is mainly belong to rural areas which depend on ground water for their drinking purpose. The fluoride concentration in ground water varies from place to place. The data show that the fluoride distribution in ground water varies from 0.01mg/l to 48 mg/l [2]. The fluoride comes into ground water by various ways, for example, weathering of rocks, industrial effluents and geoche...

  20. Technology for Water Treatment

    Science.gov (United States)

    1992-01-01

    There are approximately 500,000 water cooling towers in the United States, all of which must be kept clear of "scale" and corrosion and free of pollutants and bacteria. Electron Pure, Ltd. manufactures a hydro cooling tower conditioner as well as an automatic pool sanitizer. The pool sanitizer consists of two copper/silver electrodes placed in a chamber mounted in the pool's recirculation system. The tower conditioner combines the ionization system with a water conditioner, pump, centrifugal solids separator and timer. The system saves water, eliminates algae and operates maintenance and chemical free. The company has over 100 distributors in the U.S. as well as others in 20 foreign countries. The buildup of scale and corrosion is the most costly maintenance problem in cooling tower operation. Jet Propulsion Laboratory successfully developed a non-chemical system that not only curbed scale and corrosion, but also offered advantages in water conservation, cost savings and the elimination of toxic chemical discharge. In the system, ozone is produced by an on-site generator and introduced to the cooling tower water. Organic impurities are oxidized, and the dissolved ozone removes bacteria and scale. National Water Management, a NASA licensee, has installed its ozone advantage systems at some 200 cooling towers. Customers have saved money and eliminated chemical storage and discharge.

  1. Magnetically Separable Fe3O4/SnO2/Graphene Adsorbent for Waste Water Removal

    Science.gov (United States)

    Paramarta, V.; Taufik, A.; Saleh, R.

    2017-05-01

    Our previous study conducted the SnO2 and SnO2/graphene adsorption efficiency in Methylene Blue removal from aqueous solution, however, the difficulty of adsorbent separation from the methylene blue solution limits its efficiency. Therefore, in this work, SnO2 and SnO2/graphene was combined with Fe3O4 to improve the separation process and adsorption performance for removing the organic dyes. Fe3O4/SnO2/grapheme were synthesized by using the co-precipitation method. The graphene content was varied from 1, 3, and 5 weight percent (wt%). The crystalline phase and thermal stability of the samples were characterized by using X- ray Diffraction (XRD) and Thermal Gravimetric Analysis (TGA). The adsorption ability of the samples was investigated by using significant adsorption degradation of MB observed when the graphene in Fe3O4/SnO2 nanocomposite was added. The other parameters such as pH and initial concentration have also been investigated. The reusability was also investigated to study the stability of the samples. The fitting of equilibrium adsorption capacity result indicates that the adsorption mechanism of Fe3O4/SnO2 nanocomposite with graphene tends to follow the Langmuir adsorption isotherm model.

  2. Magnetic nanoporous carbon as an adsorbent for the extraction of phthalate esters in environmental water and aloe juice samples.

    Science.gov (United States)

    Liu, Li; Hao, Yunhui; Ren, Yiqian; Wang, Chun; Wu, Qiuhua; Wang, Zhi

    2015-05-01

    In this work, magnetic nanoporous carbon with high surface area and ordered structure was synthesized using cheap commercial silica gel as template and sucrose as the carbon source. The prepared magnetic nanoporous carbon was firstly used as an adsorbent for the extraction of phthalate esters, including diethyl phthalate, diallyl phthalate, and di-n-propyl-phthalate, from lake water and aloe juice samples. Several parameters that could affect the extraction efficiency were optimized. Under the optimum conditions, the limit of detection of the method (S/N = 3) was 0.10 ng/mL for water sample and 0.20 ng/mL for aloe juice sample. The linearity was observed over the concentration range of 0.50-150.0 and 1.0-200.0 ng/mL for water and aloe juice samples, respectively. The results showed that the magnetic nanoporous carbon has a high adsorptive capability toward the target phthalate esters in water and aloe juice samples. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Contaminated water treatment

    Science.gov (United States)

    Gormly, Sherwin J. (Inventor); Flynn, Michael T. (Inventor)

    2010-01-01

    Method and system for processing of a liquid ("contaminant liquid") containing water and containing urine and/or other contaminants in a two step process. Urine, or a contaminated liquid similar to and/or containing urine and thus having a relatively high salt and urea content is passed through an activated carbon filter to provide a resulting liquid, to remove most of the organic molecules. The resulting liquid is passed through a semipermeable membrane from a membrane first side to a membrane second side, where a fortified drink having a lower water concentration (higher osmotic potential) than the resulting liquid is positioned. Osmotic pressure differential causes the water, but not most of the remaining inorganic (salts) contaminant(s) to pass through the membrane to the fortified drink. Optionally, the resulting liquid is allowed to precipitate additional organic molecules before passage through the membrane.

  4. 100 Areas water treatment specifications

    Energy Technology Data Exchange (ETDEWEB)

    Greninger, A.B.

    1952-07-11

    This memorandum discussed review of the data from tests using alum in the treatment of pile process water, and using activated silica as a coagulant aid during period of low water temperature, which shows that this method should be substituted for the present method of treating pile process water in all 100 Areas. It was recommended that the water treatment procedures and specifications attached to this memorandum be initiated as standard practice in all 100 Areas as soon as it is possible to make the necessary equipment modifications and installations.

  5. Surface-structure dependence of water-related adsorbates on platinum

    NARCIS (Netherlands)

    Badan, C.

    2016-01-01

    Today, the energy sector is highly dependent on heterogeneous catalysis because a future solution to end our dependency on natural sources lies in generating hydrogen by splitting water. Several transition metals, such as Pt, are known to be good catalyst materials for water splitting reactions.

  6. Effect of molecular adsorbents recirculating system treatment in children with acute liver failure caused by Wilson disease.

    Science.gov (United States)

    Rustom, Najla; Bost, Muriel; Cour-Andlauer, Fleur; Lachaux, Alain; Brunet, Anne-Sophie; Boillot, Olivier; Bordet, Fabienne; Valla, Frederic; Richard, Nathalie; Javouhey, Etienne

    2014-02-01

    Because fulminant Wilson disease (WD) has an extremely poor prognosis, the use of liver support that can bridge patients to liver transplantation is lifesaving. We report the experience of albumin dialysis in acute liver failure (ALF) caused by WD in children. Chart review of children admitted for ALF secondary to acute WD and treated by the molecular adsorbents and recirculating system. Measures of copper level in blood and within the circuit during molecular adsorbents recirculating system (MARS) sessions were performed. Clinical and biological assessments after MARS session were reported. Four children, with a median age of 12.3 years, were treated from 2004 to 2009 for a severe ALF associated with acute renal failure, haemolysis, and severe cholestasis. All of the children had a new Wilson index >12. A total of 14 MARS sessions were performed, for a median duration of 7.5 hours. Tolerance was good, except for 1 child who experienced haemorrhage because of vascular injury following insertion of the dialysis catheter. A neurological improvement or stabilisation was noted in all of the children along with an improvement in the Fisher index and ammonia level after MARS treatment. MARS was able to remove copper, to decrease the serum copper level of 28% in mean, and to decrease the bilirubin and creatinin levels >25%. All of the children were subsequently underwent liver transplants with a good outcome without disability. MARS is able to remove copper and to stabilise children with ALF secondary to WD, allowing bridging to LT.

  7. Preparation of a Sepia Melanin and Poly(ethylene-alt-maleic Anhydride Hybrid Material as an Adsorbent for Water Purification

    Directory of Open Access Journals (Sweden)

    Guido Panzarasa

    2018-01-01

    Full Text Available Meeting the increasing demand of clean water requires the development of novel efficient adsorbent materials for the removal of organic pollutants. In this context the use of natural, renewable sources is of special relevance and sepia melanin, thanks to its ability to bind a variety of organic and inorganic species, has already attracted interest for water purification. Here we describe the synthesis of a material obtained by the combination of sepia melanin and poly(ethylene-alt-maleic anhydride (P(E-alt-MA. Compared to sepia melanin, the resulting hybrid displays a high and fast adsorption efficiency towards methylene blue (a common industrial dye for a wide pH range (from pH 2 to 12 and under high ionic strength conditions. It is easily recovered after use and can be reused up to three times. Given the wide availability of sepia melanin and P(E-alt-MA, the synthesis of our hybrid is simple and affordable, making it suitable for industrial water purification purposes.

  8. Preparation of a Sepia Melanin and Poly(ethylene-alt-maleic Anhydride) Hybrid Material as an Adsorbent for Water Purification.

    Science.gov (United States)

    Panzarasa, Guido; Osypova, Alina; Consolati, Giovanni; Quasso, Fiorenza; Soliveri, Guido; Ribera, Javier; Schwarze, Francis W M R

    2018-01-23

    Meeting the increasing demand of clean water requires the development of novel efficient adsorbent materials for the removal of organic pollutants. In this context the use of natural, renewable sources is of special relevance and sepia melanin, thanks to its ability to bind a variety of organic and inorganic species, has already attracted interest for water purification. Here we describe the synthesis of a material obtained by the combination of sepia melanin and poly(ethylene- alt -maleic anhydride) (P(E- alt -MA)). Compared to sepia melanin, the resulting hybrid displays a high and fast adsorption efficiency towards methylene blue (a common industrial dye) for a wide pH range (from pH 2 to 12) and under high ionic strength conditions. It is easily recovered after use and can be reused up to three times. Given the wide availability of sepia melanin and P(E- alt -MA), the synthesis of our hybrid is simple and affordable, making it suitable for industrial water purification purposes.

  9. A systematic approach of chitosan nanoparticle preparation via emulsion crosslinking as potential adsorbent in wastewater treatment.

    Science.gov (United States)

    Riegger, Benjamin R; Bäurer, Bernd; Mirzayeva, Aziza; Tovar, Günter E M; Bach, Monika

    2018-01-15

    This study investigates the impact of glutaraldehyde (glut) concentration and molecular weight (MW) of six commercially available, highly deacetylated chitosans (Chi) on nanoparticle (Chi-NP) formation by emulsion crosslinking technique and their use as potential adsorber for diclofenac (DCL) and carbamazepine (CBZ). With a glut:primary amine ratio of 1:1 and NaCl as a hydrophile, it was possible to reproducibly synthesize narrowly distributed, spherical Chi-NPs over a broad range of chitosan MW with a high yield. Increasing Chi MW resulted in larger particle sizes ranging from 109.9nm, for lowest MW, up to 200.3nm for the highest MW, measured by DLS. To evaluate the static adsorption behavior of the Chi-NPs, CBZ and DCL were used in single point adsorption experiments. An adsorption capacity of up to 351.8mgg-1 DCL for low MW Chi-NPs was observed and all Chi-NPs showed superior adsorptions when compared to untreated Chi. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. DEFLUORIDATION OF DRINKING WATER BY VARIOUS BIODEGRADABLE ADSORBENT –A REVIEW

    OpenAIRE

    Vustelamuri Padmavathi and Thatavarthi Padmini*

    2017-01-01

    Most of the developing countries like India depend on the groundwater as source of drinking water that may be contaminated by natural sources or by industrial effluents. One such contaminant is fluoride that possesses adverse effects on human health. When people consume water having fluoride (F– ) concentration >1–1.5 mg/L for a long period of time, various ailments that are collectively referred to as fluorosis occur. Various defluoridation technologies are being used to remove fluoride from...

  11. The determination of optimum condition in water hyacinth drying process by mixed adsorption drying method and modified fly ash as an adsorbent

    Science.gov (United States)

    Saputra, Asep Handaya; Putri, Rizky Anggreini

    2017-05-01

    Water hyacinth is an aquatic weed that has a very fast growth which makes it becomes a problem to the ecosystem. On the other hand, water hyacinth has a high fiber content (up to 20% by weight) which makes it potential to become raw material for composites and textile industries. As an aquatic plant, water hyacinth has a high initial moisture content that reaches more than 90%. Meanwhile the moisture content of fiber as a raw material for composite and textile industry should not be more than 10% to maintain the good quality of the products. Mixed adsorption drying method is one of the innovative method that can replace conventional drying process. Fluidization method which has been commonly used in agricultural and pharmaceutical products drying, can be enhanced by combining it with the adsorption method as performed in this study. In mixed fluidization-adsorption drying method, fly ash as adsorbent and water hyacinth fiber were put together into the fluidization column where the drying air evaporate the moisture content in water hyacinth fiber. In addition, the adsorbent adsorb the moisture content in the drying air to make the moisture content of the drying air remain low. The drying process is performed in various temperature and composition of water hyacinth and adsorbent in order to obtain the optimum drying condition. In addition, the effect of fly ash pellet and fly ash powder to the drying process was also performed. The result shows that the higher temperature and the more amount of adsorbent results in the faster drying rate. Fly ash pellet shows a better adsorption since it has a smaller pore diameter and wider surface area. The optimum temperature obtained from this study is 60°C and the optimum ratio of water hyacinth and fly ash is 50:50.

  12. On the use of carbon blacks as potential low-cost adsorbents for the removal of non-steroidal anti-inflammatory drugs from river water.

    Science.gov (United States)

    Cuerda-Correa, Eduardo M; Domínguez-Vargas, Joaquín R; Olivares-Marín, Francisco J; de Heredia, Jesús Beltrán

    2010-05-15

    The adsorption of two non-steroidal anti-inflammatory drugs (NSAIDs), namely naproxen and ketoprofen, has been studied. Low-cost carbonaceous materials such as carbon blacks have been used as the adsorbents. The influence of temperature (20-60 degrees C), pH (3-11), ionic strength (0.01-0.1M), textural properties of the adsorbents (S(BET) and pore volumes) and aqueous matrix on the adsorption process has been analyzed. The adsorption isotherms have been determined both in milli-Q aqueous solution and water from the Guadiana river. Ionic strength and pH exert a noticeable influence on the process. In general, the removal is favored at low values of temperature and pH. On the contrary, an increase of the ionic strength seems to favor the adsorption process. The use of more porous adsorbents results in a more effective removal of the pollutants. Finally, the use of natural river water results in a noticeable increase of the removal capacity of naproxen and, particularly, ketoprofen. The experimental results proved that, under the optimal operation conditions, up to 517mg/g of naproxen and 400mg/g of ketoprofen may be adsorbed, which demonstrates the promising potential of these adsorbents for the removal of the pharmaceuticals under study. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  13. Modeling and evaluation of chromium remediation from water using low cost bio-char, a green adsorbent.

    Science.gov (United States)

    Mohan, Dinesh; Rajput, Shalini; Singh, Vinod K; Steele, Philip H; Pittman, Charles U

    2011-04-15

    Oak wood and oak bark chars were obtained from fast pyrolysis in an auger reactor at 400-450 °C. These chars were characterized and utilized for Cr(VI) remediation from water. Batch sorption studies were performed at different temperatures, pH values and solid to liquid ratios. Maximum chromium was removed at pH 2.0. A kinetic study yielded an optimum equilibrium time of 48 h with an adsorbent dose of 10 g/L. Sorption studies were conducted over a concentration range of 1-100mg/L. Cr(VI) removal increased with an increase in temperature (Q(Oak wood)(°): 25 °C = 3.03 mg/g; 35 °C = 4.08 mg/g; 45 °C = 4.93 mg/g and Q(Oakbark)(°): 25 °C = 4.62 mg/g; 35 °C = 7.43 mg/g; 45 °C = 7.51 mg/g). More chromium was removed with oak bark than oak wood. The char performances were evaluated using the Freundlich, Langmuir, Redlich-Peterson, Toth, Radke and Sips adsorption isotherm models. The Sips adsorption isotherm model best fits the experimental data [high regression (R(2)) coefficients]. The overall kinetic data was satisfactorily explained by a pseudo second order rate expression. Water penetrated into the char walls exposing Cr(VI) to additional adsorption sites that were not on the surfaces of dry char pores. It is remarkable that oak chars (S(BET): 1-3m(2)g(-1)) can remove similar amounts of Cr(VI) as activated carbon (S(BET): ∼ 1000 m(2)g(-1)). Thus, byproduct chars from bio-oil production might be used as inexpensive adsorbents for water purification. Char samples were successfully used for chromium remediation from contaminated surface water with dissolved interfering ions. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Water Treatment Technology - Distribution Systems.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on distribution systems provides instructional materials for six competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: types of pipe for distribution systems, types…

  15. Phosphate Remediation and Recovery from Lake Water using Modified Iron Oxide-based Adsorbents

    Science.gov (United States)

    Adsorption behavior of Bayoxide ® E33 (E33) and three E33-modified sorbents for the removal of phosphate from lake water was investigated in this study. E33-modified sorbents were synthesized by coating with manganese and nanoparticles. Characterization was done by X-ray diffract...

  16. High Throughput Plasma Water Treatment

    Science.gov (United States)

    Mujovic, Selman; Foster, John

    2016-10-01

    The troublesome emergence of new classes of micro-pollutants, such as pharmaceuticals and endocrine disruptors, poses challenges for conventional water treatment systems. In an effort to address these contaminants and to support water reuse in drought stricken regions, new technologies must be introduced. The interaction of water with plasma rapidly mineralizes organics by inducing advanced oxidation in addition to other chemical, physical and radiative processes. The primary barrier to the implementation of plasma-based water treatment is process volume scale up. In this work, we investigate a potentially scalable, high throughput plasma water reactor that utilizes a packed bed dielectric barrier-like geometry to maximize the plasma-water interface. Here, the water serves as the dielectric medium. High-speed imaging and emission spectroscopy are used to characterize the reactor discharges. Changes in methylene blue concentration and basic water parameters are mapped as a function of plasma treatment time. Experimental results are compared to electrostatic and plasma chemistry computations, which will provide insight into the reactor's operation so that efficiency can be assessed. Supported by NSF (CBET 1336375).

  17. ACTIVATED CARBON FROM LIGNITE FOR WATER TREATMENT

    Energy Technology Data Exchange (ETDEWEB)

    Edwin S. Olson; Daniel J. Stepan

    2000-07-01

    High concentrations of humate in surface water result in the formation of excess amounts of chlorinated byproducts during disinfection treatment. These precursors can be removed in water treatment prior to disinfection using powdered activated carbon. In the interest of developing a more cost-effective method for removal of humates in surface water, a comparison of the activities of carbons prepared from North Dakota lignites with those of commercial carbons was conducted. Previous studies indicated that a commercial carbon prepared from Texas lignite (Darco HDB) was superior to those prepared from bituminous coals for water treatment. That the high alkali content of North Dakota lignites would result in favorable adsorptive properties for the very large humate molecules was hypothesized, owing to the formation of larger pores during activation. Since no standard humate test has been previously developed, initial adsorption testing was performed using smaller dye molecules with various types of ionic character. With the cationic dye, methylene blue, a carbon prepared from a high-sodium lignite (HSKRC) adsorbed more dye than the Darco HDB. The carbon from the low-sodium lignite was much inferior. With another cationic dye, malachite green, the Darco HDB was slightly better. With anionic dyes, methyl red and azocarmine-B, the results for the HSKRC and Darco HDB were comparable. A humate test was developed using Aldrich humic acid. The HSKRC and the Darco HDB gave equally high adsorption capacities for the humate (138 mg/g), consistent with the similarities observed in earlier tests. A carbon prepared from a high-sodium lignite from a different mine showed an outstanding improvement (201 mg/g). The carbons prepared from the low-sodium lignites from both mines showed poor adsorption capacities for humate. Adsorption isotherms were performed for the set of activated carbons in the humate system. These exhibited a complex behavior interpreted as resulting from two types

  18. Separation of ethanol/water azeotrope using compound starch-based adsorbents.

    Science.gov (United States)

    Wang, Yanhong; Gong, Chunmei; Sun, Jinsheng; Gao, Hong; Zheng, Shuai; Xu, Shimin

    2010-08-01

    Comparing breakthrough cures of five starch-based materials experimentally prepared for ethanol dehydration, a compound adsorptive agent ZSG-1 was formulated with high adsorption capacity, low energy and material cost. The selective water adsorption was conducted in a fixed-bed absorber packed with ZSG-1 to find the optimum conditions yielding 99.7 wt% anhydrous ethanol with high efficiency. The adsorption kinetics is well described by Bohart-Adams equation. The adsorption heat, Delta H(abs), was calculated to be -3.16 x 10(4)J mol(-1) from retention data by inverse gas chromatography. Results suggested that water entrapment in ZSG-1 is a exothermic and physisorption process. Also, ZSG-1 is recyclable for on-site multiple-use and then adapt for upstream fermentation process after saturation, avoiding pollution through disposal. (c) 2010 Elsevier Ltd. All rights reserved.

  19. Banana peel as an adsorbent for removing atrazine and ametryne from waters.

    Science.gov (United States)

    Silva, Claudineia R; Gomes, Taciana F; Andrade, Graziela C R M; Monteiro, Sergio H; Dias, Ana C R; Zagatto, Elias A G; Tornisielo, Valdemar L

    2013-03-13

    The feasibility of using banana peel for removal of the pesticides atrazine and ametryne from river and treated waters has been demonstrated, allowing the design of an efficient, fast, and low-cost strategy for remediation of polluted waters. The conditions for removal of these pesticides in a laboratory scale were optimized as sample volume = 50 mL, banana mass = 3.0 g, stirring time = 40 min, and no pH adjustment necessary. KF(sor) values for atrazine and ametryne were evaluated as 35.8 and 54.1 μg g(-1) (μL mL(-1)) by using liquid scintillation spectrometry. Adsorption was also evaluated by LC-ESI-MS/MS. As quantification limits were 0.10 and 0.14 μg L(-1) for both pesticides, sample preconcentration was not needed. Linear analytical curves (up to 10 μg L(-1)), precise results (RSD 90% removal efficiency were attained for both pesticides. Water samples collected near an intensively cultivated area were adequately remedied.

  20. Extraction of Phosphate from Polluted Waters Using Calcium Alginate Beads Doped with Active Carbon Derived from A. aspera Plant as Adsorbent

    Directory of Open Access Journals (Sweden)

    Ravulapalli Sujitha

    2017-01-01

    Full Text Available An adsorbent prepared by entrapping active carbon derived from the stems of Achyranthes aspera plant in the calcium alginate beads (CABAA has been investigated for its adsorption nature towards the removal of phosphate by varying various physicochemical parameters. Surface morphological studies are made using FTIR, XRD, FESEM, and EDX. The sorption mechanism is analyzed using Freundlich, Langmuir, Dubinin-Radushkevich, and Temkin adsorption isotherms. The adsorption kinetics is found to follow the pseudo-second-order model. Thermodynamic parameters are analyzed and found that the adsorption is endothermic and nonspontaneous in nature. The maximum amount of phosphate adsorbed onto CABAA is found to be 133.3 mg/g of active carbon and, furthermore, the adsorbent is highly selective. The methodology developed is successfully applied to polluted water samples.

  1. Speciation of trace metals in natural waters: the influence of an adsorbed layer of natural organic matter (NOM) on voltammetric behaviour of copper.

    Science.gov (United States)

    Louis, Yoann; Cmuk, Petra; Omanović, Dario; Garnier, Cédric; Lenoble, Véronique; Mounier, Stéphane; Pizeta, Ivanka

    2008-01-07

    The influence of an adsorbed layer of the natural organic matter (NOM) on voltammetric behaviour of copper on a mercury drop electrode in natural water samples was studied. The adsorption of NOM strongly affects the differential pulse anodic stripping voltammogram (DPASV) of copper, leading to its distortion. Phase sensitive ac voltammetry confirmed that desorption of adsorbed NOM occurs in general at accumulation potentials more negative than -1.4V. Accordingly, an application of negative potential (-1.6V) for a very short time at the end of the accumulation time (1% of total accumulation time) to remove the adsorbed NOM was introduced in the measuring procedure. Using this protocol, a well-resolved peak without interferences was obtained. It was shown that stripping chronopotentiogram of copper (SCP) in the depletive mode is influenced by the adsorbed layer in the same manner as DPASV. The influence of the adsorbed NOM on pseudopolarographic measurements of copper and on determination of copper complexing capacity (CuCC) was demonstrated. A shift of the peak potential and the change of the half-peak width on the accumulation potential (for pseudopolarography) and on copper concentration in solution (for CuCC) were observed. By applying a desorption step these effects vanished, yielding different final results.

  2. Waste water treatment by flotation

    Directory of Open Access Journals (Sweden)

    Camelia Badulescu

    2005-11-01

    Full Text Available The flotation is succesfully applied as a cleaning method of waste water refineries, textile fabrics (tissues, food industry, paper plants, oils plants, etc. In the flotation process with the released air, first of all, the water is saturated with air compressed at pressures between 0,3 – 3 bar, followed by the relaxed phenomenon of the air-water solution in a flotation cell with slowly flowing. The supersaturation could be applied in the waste water treatment. In this case the waste water, which is in the atmospheric equilibrum, is introduced in a closed space where the depression is 0,3 – 0,5 bar. Our paper presents the hypobaric flotation cell and the technological flow of cleaning of domestic waste waters

  3. Contaminants in drinking water and its mitigation using suitable adsorbents: an overview.

    Science.gov (United States)

    Gopal, Krishna; Srivastava, Sachin Behari; Shukla, Satish; Bersillon, J L

    2004-10-01

    Various options are applicable for the removal of water pollutants included reverse osmosis, ion exchange, coagulation, co-precipitation, catalytic reduction, herbal filtration, electrodialysis and adsorption. This paper deals with the sorption phenomena for the removal of pollutants from drinking water. Attempts have been made to use low cost sorbents developed by pretreatment/activation/impregnation with alkalis, acids, iron oxide, manganese dioxide, ferric chloride, alum, lime, aluminum salts with natural products/indigenous minerals viz. activated alumina, activated carbon, groundnut husk, saw dust, chemically coated sand, fly ash, zeolites, clay minerals and other plant products. Application of Freundich and Langmuir isotherms were used to assess the adsorption capacity. Equilibrium isotherms were determined at optimum temperature and pH to characterize the sorption process. Statistical parameters such as mass transfer coefficients, multiple regression analysis were applied to establish the mechanism. It is suggested that the characterization of suitable, and exhausted sorbent through the application of fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray fluorescence (XRF) is essential to establish its surface bonding. Scope for safety evaluation and risk assessment to human and biosphere may provide the guideline and predication to the regulatory agencies for its sustainable use and safe disposal The ecotoxicological assessment of the leachates and low cost removal technology are discussed in this paper.

  4. Regenerative adsorbent heat pump

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative adsorbent heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system and at least a portion of the heat of adsorption. A series of at least four compressors containing an adsorbent is provided. A large amount of heat is transferred from compressor to compressor so that heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  5. Solid-phase microextraction of phthalate esters in water sample using different activated carbon-polymer monoliths as adsorbents.

    Science.gov (United States)

    Lirio, Stephen; Fu, Chung-Wei; Lin, Jhih-Yun; Hsu, Meng-Ju; Huang, Hsi-Ya

    2016-07-13

    In this study, the application of different activated carbon-polymer (AC-polymer) monoliths as adsorbents for the solid-phase microextraction (SPME) of phthalate esters (PAEs) in water sample were investigated. The activated carbon (AC) was embedded in organic polymers, poly(butyl methacrylate-co-ethylene dimethacrylate) (poly(BMA-EDMA)) or poly(styrene-co-divinylbenzene) (poly(STY-DVB)), via a 5-min microwave-assisted or a 15-min water bath heating polymerization. Preliminary investigation on the performance of the native poly(BMA-EDMA) and poly(STY-DVB) demonstrated remarkable adsorption efficiencies for PAEs. However, due to the strong hydrophobic, π-π, and hydrogen bonding interactions between the analytes and polymers, low extraction recoveries were achieved. In contrast, the presence of AC in native polymers not only enhanced the adsorption efficiencies but also assisted the PAE desorption, especially for AC-poly(STY-DVB) with extraction recovery ranged of 76.2-99.3%. Under the optimized conditions, the extraction recoveries for intra-, inter-day and column-to-column were in the range of 76.5-100.8% (<3.7% RSDs), 77.2-97.6% (<5.6% RSDs) and 75.5-99.7% (<6.2% RSDs), respectively. The developed AC-poly(STY-DVB) monolithic column showed good mechanical stability, which can be reused for more than 30 extraction times without any significant loss in the extraction recoveries of PAEs. The AC-poly(STY-DVB) monolithic column was successfully applied in SPME of PAEs in water sample with extraction recovery ranged of 78.8%-104.6% (<5.5% RSDs). Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Efficient removal of arsenic from water using a granular adsorbent: Fe-Mn binary oxide impregnated chitosan bead.

    Science.gov (United States)

    Qi, Jianying; Zhang, Gaosheng; Li, Haining

    2015-10-01

    A novel sorbent of Fe-Mn binary oxide impregnated chitosan bead (FMCB) was fabricated through impregnating Fe-Mn binary oxide into chitosan matrix. The FMCB is sphere-like with a diameter of 1.6-1.8 mm, which is effective for both As(V) and As(III) sorption. The maximal sorption capacities are 39.1 and 54.2 mg/g, respectively, outperforming most of reported granular sorbents. The arsenic was mainly removed by adsorbing onto the Fe-Mn oxide component. The coexisting SO4(2-), HCO3(-) and SiO3(2-) have no great influence on arsenic sorption, whereas, the HPO4(2-) shows negative effects. The arsenic-loaded FMCB could be effectively regenerated using NaOH solution and repeatedly used. In column tests, about 1500 and 3200 bed volumes of simulated groundwater containing 233 μg/L As(V) and As(III) were respectively treated before breakthrough. These results demonstrate the superiority of the FMCB in removing As(V) and As(III), indicating that it is a promising candidate for arsenic removal from real drinking water. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Nuclear transfer and anisotropic motional spin phenomena: relaxation time temperature dependence studies of water adsorbed on silica gel. Part IV

    Energy Technology Data Exchange (ETDEWEB)

    Woessner, D.E.; Zimmerman, J.R.

    1962-12-15

    An experimental investigation of the temperature dependence of the nuclear magnetic resonance relaxation phenomena of water vapor adsorbed on silica gel is described. Two-component relaxation data are observed. With temperature increase, the longer T/sub 2/ value decreases while its fractional population increases. These data are shown to be consistent with nuclear transfers between two state environments possessing distinct relaxation characteristics. and a comparison with theory is made. Evidence of a change of surface characteristics is presented; for early experiments, two-component longitudinal relaxation occurs below a transition temperature; in later experiments, only one-component T/sub 1/ behavior is found. A theory for an anisotropic motional model for nuclear magnetic dipole-dipole relaxation on surfaces is presented. The motional model is random reorientation of the interproton vector about an axis normal to the surface that occurs much faster than the time dependence of the angle between the vector and this axis. The relaxation processes are thus related to multiple nuclear correlation times. Consequences of an anisotropic model agree with experimental observations. (auth)

  8. Defluoridation of water using as-synthesized Zn/Al/Cl anionic clay adsorbent: Equilibrium and regeneration studies

    Energy Technology Data Exchange (ETDEWEB)

    Mandal, S., E-mail: s.mandal@ncl.res.in [Chemical Engineering and Process Development Division, National Chemical Laboratory, Pune (India); Mayadevi, S. [Chemical Engineering and Process Development Division, National Chemical Laboratory, Pune (India)

    2009-08-15

    Zn/Al/Cl anionic clay has been synthesized by co-precipitation method and applied for adsorption of fluoride in aqueous medium. Equilibrium adsorption data were fitted to Langmuir, Freundlich, Temkin, and Generalized isotherm equations. Thermodynamic parameters like {Delta}G and {Delta}H values show the feasibility and exothermic nature of the adsorption process. Influence of solution pH and presence of other anions on fluoride adsorption by the clay has also been studied. Presence of carbonate in water was found to have an adverse effect on fluoride adsorption by the clay. pH{sub pzc} of the clay has been found to be 8.97. A two-step 1st order kinetic model was used to explain the fluoride adsorption kinetics of the as-synthesized clay. It was possible to regenerate the adsorbent with an aqueous solution of 0.01 M NaOH and the effect of regeneration on fluoride adsorption was reported up to five regeneration cycles.

  9. Defluoridation of water using as-synthesized Zn/Al/Cl anionic clay adsorbent: equilibrium and regeneration studies.

    Science.gov (United States)

    Mandal, S; Mayadevi, S

    2009-08-15

    Zn/Al/Cl anionic clay has been synthesized by co-precipitation method and applied for adsorption of fluoride in aqueous medium. Equilibrium adsorption data were fitted to Langmuir, Freundlich, Temkin, and Generalized isotherm equations. Thermodynamic parameters like DeltaG and DeltaH values show the feasibility and exothermic nature of the adsorption process. Influence of solution pH and presence of other anions on fluoride adsorption by the clay has also been studied. Presence of carbonate in water was found to have an adverse effect on fluoride adsorption by the clay. pH(pzc) of the clay has been found to be 8.97. A two-step 1st order kinetic model was used to explain the fluoride adsorption kinetics of the as-synthesized clay. It was possible to regenerate the adsorbent with an aqueous solution of 0.01 M NaOH and the effect of regeneration on fluoride adsorption was reported up to five regeneration cycles.

  10. Extraction-preconcentration Mercury ion by Ghezeljeh montmorillonite nanoclay as a new native adsorbent from food and water samples

    Directory of Open Access Journals (Sweden)

    Zahra Hassanzadeh Siahpoosh

    2017-01-01

    Full Text Available Ghezeljeh montmorillonite nanoclay or “Geleh-Sar-Shoor” (means head-washing clay used as a native adsorbent to extraction-preconcentration mercury ions from a variety of real water and fish samples have been investigated in a batch system followed by atomic absorption spectroscopy (AAS with vapor generation accessory (VGA system. The clay was characterized by using FT-IR, SEM-EDS, XRF, XRD, CEC, Specific surface area and Zeta potential. The results of XRD, FT-IR, Zeta potential and CEC of the Ghezeljeh clay confirm that montmorillonite is the dominant mineral phase. On the basis of on SEM images, the distance between the layers is in nm level. The outcome of varying parameters and interfering ions were studied. Detection and quantification limits, preconcentration factor, and adsorption capacity were calculated. The Langmuir and Freundlich equations showed the finest fit to the equilibrium data. The adsorption procedure follows a pseudo-second-order reaction pattern. Calculation of ΔG0, ΔH0 and ΔS0 displayed that the nature of Hg(II ions adsorption is endothermic and favorable at upper temperature.

  11. Comparison of the dilational behaviour of adsorbed milk proteins at the air-water and oil-water interfaces.

    NARCIS (Netherlands)

    Williams, A.; Prins, A.

    1996-01-01

    The interfacial dilational properties of two milk proteins, β-casein and β-lactoglobulin, have been compared at the air-water and paraffin oil-water interfaces. The measurements were performed as a function of bulk protein concentration using a modified Langmuir trough technique at a frequency of

  12. Aluminium fumarate metal-organic framework: A super adsorbent for fluoride from water

    Energy Technology Data Exchange (ETDEWEB)

    Karmakar, Sankha [Department of Chemical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India); Dechnik, Janina [Institut fur Anorganische Chemie und Strukturchemie, Heinrich-Heine-Universität Düsseldorf, 40204 Düsseldorf (Germany); Janiak, Christoph, E-mail: janiak@uni-duesseldorf.de [Institut fur Anorganische Chemie und Strukturchemie, Heinrich-Heine-Universität Düsseldorf, 40204 Düsseldorf (Germany); De, Sirshendu, E-mail: sde@che.iitkgp.ernet.in [Department of Chemical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)

    2016-02-13

    Highlights: • Maximum adsorption of fluoride on AlFu MOF occurred at 293 K. • Maximum adsorption capacity for fluoride was 600 mg/g at 293 K. • The MOF exhibited adequate charge characteristic and high surface area (1156 m{sup 2}/g). • Second order reaction and intra particle diffusion (first 1.5 h) was prevalent. • AlFu MOF exhibited high potential for fluoride removal from water. - Abstract: Potential of aluminium fumarate metal organic framework (MOF) for fluoride removal from groundwater has been explored in this work. The laboratory produced MOF exhibited characteristics similar to the commercial version. MOF was found to be micro-porous with surface area of 1156 m{sup 2}/g and average pore size 17 Å. Scanning electron micrograph of the AlFu MOF showed minute pores and texture was completely different from either of the parent materials. Change in the composition of AlFu MOF after fluoride adsorption was evident from powder X-ray diffraction analysis. Thermal stability of the AlFu MOF up to 700 K was established by thermo-gravimetric analysis. Incorporation of fluoride phase after adsorption was confirmed by X-ray fluorescence analysis. As observed from FTIR study, hydroxyl ions in AlFu MOF were substituted by fluoride. 0.75 g/l AlFu MOF was good enough for complete removal of 30 mg/l fluoride concentration in feed solution. The maximum adsorption capacity for fluoride was 600, 550, 504 and 431 mg/g, respectively, at 293, 303, 313 and 333 K.

  13. Cleaning and reusing backwash water of water treatment plants

    Science.gov (United States)

    Skolubovich, Yury; Voytov, Evgeny; Skolubovich, Alexey; Ilyina, Lilia

    2017-10-01

    The article deals with the treatment of wash water of water treatment plants open water sources. The results of experimental studies on the choice of effective reagent, cleaning and disposal of wash water of filters. The paper proposed a new two-stage purification technology and multiple reuse of wash water of water purification stations from open surface sources

  14. Laccase Immobilized on a PAN/Adsorbents Composite Nanofibrous Membrane for Catechol Treatment by a Biocatalysis/Adsorption Process

    Directory of Open Access Journals (Sweden)

    Qingqing Wang

    2014-03-01

    Full Text Available The treatment of catechol via biocatalysis and adsorption with a commercial laccase immobilized on polyacrylonitrile/montmorillonite/graphene oxide (PAN/MMT/GO composite nanofibers was evaluated with a homemade nanofibrous membrane reactor. The properties in this process of the immobilized laccase on PAN, PAN/MMT as well as PAN/MMT/GO with different weight ratios of MMT and GO were investigated. These membranes were successfully applied for removal of catechol from an aqueous solution. Scanning electron microscope images revealed different morphologies of the enzyme aggregates on different supports. After incorporation of MMT or MMT/GO, the optimum pH showed an alkaline shift to 4, compared to 3.5 for laccase immobilized on pure PAN nanofibers. The optimum temperature was at 55 °C for all the immobilized enzymes. Besides, the addition of GO improved the operational stability and storage stability. A 39% ± 2.23% chemical oxygen demand (COD removal from the catechol aqueous solution was achieved. Experimental results suggested that laccase, PAN, adsorbent nanoparticles (MMT/GO can be combined together for catechol treatment in industrial applications.

  15. Heterogeneous radiolysis of water: effect of the concentration of water in the adsorbed phase on the hydrogen yield

    Energy Technology Data Exchange (ETDEWEB)

    Garibov, A.A.; Gezalov, K.B.; Velibekova, G.Z.; Khudiev, A.T.; Ramazanova, M.K.; Kasumov, R.D.; Agaev, T.N.; Gasanov, A.M.

    1988-05-01

    A study was carried out on the effect of the water concentration on the molecular hydrogen yield during the heterogeneous radiolysis of water in the presence of KSK silica gel and NaX zeolite. The molecular hydrogen yield was found to rise with an increase in the degree of filling in the range /theta/ = 0-1, while the limiting values of G/sub total/(H/sub 2/) are reached in the region of unimolecular filling of the active centers. In order to clarify the mechanism of the heterogeneous radiolysis of water in the presence of zeolite systems, the ESR method was used to investigate the rate of accumulation of radiation defects in zeolite HLaY and also the water radiolysis process in its presence.

  16. Surface Water Treatment Workshop Manual.

    Science.gov (United States)

    Ontario Ministry of the Environment, Toronto.

    This manual was developed for use at workshops designed to increase the knowledge of experienced water treatment plant operators. Each of the fourteen lessons in this document has clearly stated behavioral objectives to tell the trainee what he should know or do after completing that topic. Areas covered in this manual include: basic water…

  17. CFD in drinking water treatment

    NARCIS (Netherlands)

    Wols, B.A.

    2010-01-01

    Hydrodynamic processes largely determine the efficacy of drinking water treatment systems, in particular disinfection systems. A lack of understanding of the hydrodynamics has resulted in suboptimal designs of these systems. The formation of unwanted disinfection-by-products and the energy

  18. In-vitro synthesis of marble apatite as a novel adsorbent for removal of fluoride ions from ground water: An ultrasonic approach.

    Science.gov (United States)

    Mehta, Dhiraj; Mondal, Poonam; Saharan, Virendra Kumar; George, Suja

    2018-01-01

    Marble waste powder consisting of calcium and magnesium compounds was used to synthesize a novel biocompatible product, marble apatite (MA) primarily hydroxyapatite (Hap) for applications in defluoridation of drinking water. Synthesis of marble apatite was carried out by using calcium compounds (mixture of hydroxide and nitrate) extracted from marble waste powder which was treated with potassium dihydrogen phosphate at 80°C under alkaline conditions using conventional precipitation method (CM) and ultrasonication method (USM). Qualitative analysis of synthesized marble apatite from both the methods was carried out using FTIR, phase analysis by XRD and microstructure analysis by SEM and TEM. When ultrasonication (USM) method was used, the yield of marble apatite was improved from 67.5% to 78.4%, with reduction in crystallite size (58.46nm), lesser agglomeration and comparatively well-defined spherical morphology compared to the CM method. Studies also include estimation of the defluoridation capacity of MA as an adsorbent for drinking water treatment and effects of process parameters such as pH, contact time, initial fluoride concentration, dosage and presence of other co-ions on fluoride removal capacity. The results showed that the experimental adsorption capacity of the marble apatite synthesized using USM method was significantly higher (1.826mg/g) than marble apatite synthesized using conventional method (0.96mg/g) at pH 7 with a contact time of 90min. The mechanism of adsorption was studied, and it was observed that Langmuir isotherm model fitted best to the experimental data, while the kinetic studies revealed that the process followed pseudo-second order model. This novel compound, marble apatite synthesized from marble waste powder is found to be promising for defluoridation of drinking water and will help in alleviating the problems of fluorosis as well as reduce the problems of disposal of marble waste. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Preparation of dye waste-barium sulfate hybrid adsorbent and application in organic wastewater treatment.

    Science.gov (United States)

    Hu, Zhang-Jun; Xiao, Yan; Zhao, Dan-Hua; Shen, Yu-Lin; Gao, Hong-Wen

    2010-03-15

    A new hybrid material was developed by the template-free hybridization of weak acidic pink red B (APRB, C.I. 18073) with BaSO(4). The composition and structure of the material were determined and characterized. In contrast to conventional sorbents, the hybrid material has a specific surface area of 0.89 m(2)/g, but it contains lots of negative charges and lipophilic groups as the basis of specific adsorption. The efficient removal of cationic dyes and persistent organic pollutants (POPs) indicates that it has an improved adsorption capacity and selectivity with a short removal time less than 2 min; while the hybrid sorbents fit the Langmuir isotherm model, and follow the octanol-water partition law. Instead of using APRB reagent, an APRB-producing wastewater was reused to prepare the cost-effective sorbent, and the equilibrium adsorption capacities of which reached 222 and 160 mg/g for EV and BPR, respectively. The sorbents was then used to treat three wastewater samples with satisfactory results of over 97% decolonization and 88% COD-decreasing. In addition, the hybrid sorbent was regenerated from sludge over five cycles, and its adsorption capacity was not appreciably changed. This work has developed a simple and eco-friendly method for synthesizing a practical and efficient sorbent. (c) 2009 Elsevier B.V. All rights reserved.

  20. A comparison of different concentration methods for the detection of viruses present in bottled waters and those adsorbed to water bottle surfaces.

    Science.gov (United States)

    Huguet, L; Carteret, C; Gantzer, C

    2012-04-01

    This study aimed to provide a tool for selecting the best approach to virological testing of bottled waters. Different methods were investigated. Method A examined the recovery of virus RNA following in situ lysis of virus particles in the aqueous phase and of those adhered to the bottle wall, method B examined the recovery of virus RNA following lysis of virus particles in the aqueous phase, and method C examined the recovery of intact virus particles. Method C generated the lowest genome recovery rate regardless of the water and virus type used, therefore comparison was mainly conducted between methods A and B.The effects of independent variables on the viral RNA recovery rate were determined by full factorial design. These independent variables included three waters (differing in mineral composition), four viruses (poliovirus 1, hepatitis A virus, Norovirus, and the MS2 phage), three incubation times (0, 10, and 20 days), and two methods (A and B). According to the results, each factor influenced the recovery rate of viral RNA with the exception of incubation time. Statistical analysis identified interactions between the factors. The strongest interactions involved the water and virus types, as well as the methods. The results suggested that method A should be used for the concentration and detection of hepatitis A virus, regardless of the divalent cation concentration of the bottled water. Method A was most suitable for water with the highest mineral content (divalent cation concentration of 250 mgL(-1)) and for the analysis of viruses capable of adsorbing onto the bottle walls (Poliovirus 1). Method B could be recommended for the analysis of water whose cation concentration is unknown. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Novel carboxymethyl cellulose based nanocomposite membrane: Synthesis, characterization and application in water treatment.

    Science.gov (United States)

    Saber-Samandari, Samaneh; Saber-Samandari, Saeed; Heydaripour, Samira; Abdouss, Majid

    2016-01-15

    Significant efforts have been made to develop composite membranes with high adsorption efficiencies for water treatment. In this study, a carboxymethyl cellulose-graft-poly(acrylic acid) membrane was synthesized in the presence of silica gel, which was used as an inorganic support. Then, different amounts of bentonite were introduced to the carboxymethyl cellulose (CMC) grafted networks as a multifunctional crosslinker, and nanocomposite membranes were prepared. The nanocomposite membranes were characterized using Fourier transform infrared spectroscopy, and scanning electron microscopy, which revealed their compositions and surface morphologies. The novel synthesized nanocomposite membranes were utilized as adsorbents for the removal of crystal violet (CV) and cadmium (Cd (II)) ions, which were selected as representatives of a dye and a heavy metal, respectively. We explored the effects of various parameters, such as time, pH, temperature, initial concentration of adsorbate solution and amount of adsorbent, on membrane adsorption capacity. Furthermore, the kinetic, adsorption isotherm models and thermodynamic were employed for the description of adsorption processes. The maximum adsorption capacities of membranes for CV and Cd (II) ions were found to be 546 and 781 mg g(-1), respectively. The adsorption of adsorbate ions by all types of nanocomposite membranes followed pseudo-second-order kinetic model and was best fit with the Freundlich adsorption isotherm. The results indicated that the synthesized nanocomposite membrane is an efficient adsorbent for the removal of cationic dye and metal contaminants from aqueous solution during water treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Application of near infrared spectroscopy for the determination of adsorbed p-nitrophenol on HDTMA organoclay—implications for the removal of organic pollutants from water

    Science.gov (United States)

    Zhou, Qin; Xi, Yunfei; He, Hongping; Frost, Ray L.

    2008-03-01

    NIR spectroscopy has been used to measure the adsorption of p-nitrophenol on untreated montmorillonite and surfactant exchanged montmorillonite. p-Nitrophenol is characterised by an intense NIR band at 8890 cm -1 which shifts to 8840 cm -1 upon adsorption on organoclay. The band was not observed for p-nitrophenol adsorbed on untreated montmorillonite. Both the montmorillonite and the surfactant modified montmorillonite are characterised by NIR bands at 7061 and 6791 cm -1. The organoclay is characterised by two prominent bands at 5871 and 5667 cm -1 assigned to the fundamental overtones of the mid-IR bands at 2916 and 2850 cm -1. A band at 6017 cm -1 is attributed to the p-nitrophenol adsorbed on the organoclay. The band is not observed for the montmorillonite with adsorbed p-nitrophenol. It is concluded that p-nitrophenol is adsorbed to significantly greater amounts on the organoclay compared with the untreated montmorillonite. The implication is that organoclays are most useful for removing organic molecules from water through adsorption.

  3. Treatment of Highly Turbid Water by Polyaluminum Ferric Chloride (PAFCL

    Directory of Open Access Journals (Sweden)

    Fazel Fazel Mohammadi-Moghaddam

    2015-10-01

    Full Text Available Background & Aims of the Study: In some situation like rainfall seasons raw water become very turbid so it affected the water treatment plant processes and quality of produced water. Treatment of very high turbid water has some concerns like precursors for disinfection by-products and very loading rate of particle on filter's media and consequently increases in water consumption for filter backwash. This paper investigates the performance of a composite inorganic polymer of aluminium and ferric salt, Polyaluminium ferric chloride (PAFCl, for the removal of turbidity, color and natural organic matter (NOM from high turbid water. Materials and Methods: Experiments were carried out by Jar test experiment by synthetic water samples with 250 and 500 NTU turbidity that prepared in laboratory. Results: The results of conventional jar test showed that the optimum pH for coagulation of water sample was 7.5 to 8 and optimum dosage of the coagulant was 10 mg/L. Removal efficiency of turbidity, color and UV adsorbent at 254 nm at optimum dose and pH without filtration was 99.92%, 100% and 80.6% respectively for first sample (250 NTU and 99.95%, 99.49% and 84.77 for second sample (500 NTU respectively. Conclusion: It concluded that polyaluminium ferric chloride has a very good efficiency for the removal of turbidity, color and organic matter in high turbid water. Also it can be select as a coagulant for high turbid water and some waste water from water treatment plant like filter backwash water.

  4. Sn(II) oxy-hydroxides as potential adsorbents for Cr(VI)-uptake from drinking water: An X-ray absorption study.

    Science.gov (United States)

    Pinakidou, Fani; Kaprara, Efthimia; Katsikini, Maria; Paloura, Eleni C; Simeonidis, Konstantinos; Mitrakas, Manassis

    2016-05-01

    The feasibility of implementing a Sn(II) oxy-hydroxide (Sn6O4(OH)4) for the reduction and adsorption of Cr(VI) in drinking water treatment was investigated using XAFS spectroscopies at the Cr-K-edge. The analysis of the Cr-K-edge XANES and EXAFS spectra verified the effective use of Sn6O4(OH)4 for successful Cr(VI) removal. Adsorption isotherms, as well as dynamic Rapid Small Scale Test (RSSCT) in NSF water matrix showed that Sn6O4(OH)4 can decrease Cr(VI) concentration below the upcoming regulation limit of 10μg/L for drinking water. Moreover, an uptake capacity of 7.2μg/mg at breakthrough concentration of 10μg/L was estimated from the RSSCT, while the residual Cr(VI) concentration ranged at sub-ppb level for a significant period of the experiment. Furthermore, no evidence for the formation of Cr(OH)3 precipitates was found. On the contrary, Cr(III)-oxyanions were chemisorbed onto SnO2, which was formed after Sn(II)-oxidation during Cr(VI)-reduction. Nevertheless, changes in the type of Cr(III)-inner sphere complexes were observed after increasing surface coverage: Cr(III)-oxyanions preferentially sorb in a geometry which combines both bidentate binuclear ((2)C) and monodentate ((1)V) geometries, at the expense of the present bidentate mononuclear ((2)E) contributions. On the other hand, the pH during sorption does not affect the adsorption mechanism of Cr(III)-species. The implementation of Sn6O4(OH)4 in water treatment technology combines the advantage of rapidly reducing a large amount of Cr(VI) due to donation of two electrons by Sn(II) and also the strong chemisorption of Cr(III) in a combination of the (2)C and (1)V configurations, which enhances the safe disposal of spent adsorbents. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Potential of polyaniline modified clay nanocomposite as a selective decontamination adsorbent for Pb(II) ions from contaminated waters; kinetics and thermodynamic study.

    Science.gov (United States)

    Piri, Somayeh; Zanjani, Zahra Alikhani; Piri, Farideh; Zamani, Abbasali; Yaftian, Mohamadreza; Davari, Mehdi

    2016-01-01

    Nowadays significant attention is to nanocomposite compounds in water cleaning. In this article the synthesis and characterization of conductive polyaniline/clay (PANI/clay) as a hybrid nanocomposite with extended chain conformation and its application for water purification are presented. Clay samples were obtained from the central plain of Abhar region, Abhar, Zanjan Province, Iran. Clay was dried and sieved before used as adsorbent. The conductive polyaniline was inflicted into the layers of clay to fabricate a hybrid material. The structural properties of the fabricated nanocomposite are studied by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM). The elimination process of Pb(II) and Cd(II) ions from synthetics aqueous phase on the surface of PANI/clay as adsorbent were evaluated in batch experiments. Flame atomic absorption instrument spectrophotometer was used for determination of the studied ions concentration. Consequence change of the pH and initial metal amount in aqueous solution, the procedure time and the used adsorbent dose as the effective parameters on the removal efficiency was investigated. Surface characterization was exhibited that the clay layers were flaked in the hybrid nanocomposite. The results show that what happen when a nanocomposite polyaniline chain is inserted between the clay layers. The adsorption of ions confirmed a pH dependency procedure and a maximum removal value was seen at pH 5.0. The adsorption isotherm and the kinetics of the adsorption processes were described by Temkin model and pseudo-second-order equation. Time of procedure, pH and initial ion amount have a severe effect on adsorption efficiency of PANI/clay. By using suggested synthesise method, nano-composite as the adsorbent simply will be prepared. The prepared PANI/clay showed excellent adsorption capability for decontamination of Pb ions from contaminated water. Both of suggested synthesise and

  6. Amorphous boron-doped sodium titanates hydrates: Efficient and reusable adsorbents for the removal of Pb{sup 2+} from water

    Energy Technology Data Exchange (ETDEWEB)

    Di Bitonto, Luigi; Volpe, Angela; Pagano, Michele; Bagnuolo, Giuseppe; Mascolo, Giuseppe [CNR-IRSA, Via de Blasio 5, 70132 Bari (Italy); La Parola, Valeria [CNR-ISMN, Via U. La Malfa, 153, 90146 Palermo (Italy); Di Leo, Paola [CNR-IMAA, Via S. Loja, Tito Scalo (PZ) (Italy); Pastore, Carlo, E-mail: carlo.pastore@ba.irsa.cnr.it [CNR-IRSA, Via de Blasio 5, 70132 Bari (Italy)

    2017-02-15

    Highlights: • Amorphous B-doped sodium titanates hydrates were mildly synthesized. • These compounds resulted efficiently used in removing Pb{sup 2+} from natural water. • Adsorption occurs with a partial ionic exchange mechanism. • Adsorbents were easily recoverable and reusable for further new cycles. - Abstract: Amorphous titanium hydroxide and boron-doped (B-doped) sodium titanates hydrates were synthetized and used as adsorbents for the removal of Pb{sup 2+} from water. The use of sodium borohydride (NaBH{sub 4}) and titanium(IV) isopropoxide (TTIP) as precursors permits a very easy synthesis of B-doped adsorbents at 298 K. The new adsorbent materials were first chemically characterized (XRD, XPS, SEM, DRIFT and elemental analysis) and then tested in Pb{sup 2+} adsorption batch experiments, in order to define kinetics and equilibrium studies. The nature of interaction between such sorbent materials and Pb{sup 2+} was also well defined: besides a pure adsorption due to hydroxyl interaction functionalities, there is also an ionic exchange between Pb{sup 2+} and sodium ions even working at pH 4.4. Langmuir model presented the best fitting with a maximum adsorption capacity up to 385 mg/g. The effect of solution pH and common ions (i.e. Na{sup +}, Ca{sup 2+} and Mg{sup 2+}) onto Pb{sup 2+} sorption were also investigated. Finally, recovery was positively conducted using EDTA. Very efficient adsorption (>99.9%) was verified even using tap water spiked with traces of Pb{sup 2+} (50 ppb).

  7. Investigation of feasibility of bamboo charcoal as solid-phase extraction adsorbent for the enrichment and determination of four phthalate esters in environmental water samples.

    Science.gov (United States)

    Zhao, Ru-Song; Wang, Xia; Yuan, Jin-Peng; Lin, Jin-Ming

    2008-03-07

    This paper demonstrates, for the first time, that adsorptive potential of bamboo charcoal for solid-phase extraction of phthalate esters was investigated. The four phthalate esters, dimethyl phthalate (DMP), diethyl phthalate (DEP), butyl benzyl phthalate (BBP) and di-n-butyl phthalate (DBP), are quantitatively adsorbed on a bamboo charcoal packed cartridge, then the analytes retained on the cartridge are quantitatively desorbed with optimum amounts of acetone. Finally, the analytes in the eluant acetone are determined by high-performance liquid chromatography-ultraviolet detectior. Important parameters influencing the extraction efficiency, such as eluant and its volume, flow rate of sample, sample volume, pH, the amount of adsorbent and ionic strength were investigated and optimized in detail. Under the optimum conditions, the limits of detection were 0.35-0.43 microg/L for four phthalate esters. The proposed method has been applied to the analysis of rainwater and tap water samples. And satisfactory spiked recoveries were obtained in the range of 75.0-114.2%. All the results indicated that the bamboo charcoal has great potential as a novel adsorbent material for the enrichment and determination of phthalate esters in real environmental water samples.

  8. Some Observations on the Development of Superior Photocatalytic Systems for Application to Water Purification by the “Adsorb and Shuttle” or the Interphase Charge Transfer Mechanisms

    Directory of Open Access Journals (Sweden)

    Cooper Langford

    2014-11-01

    Full Text Available Adsorb and shuttle (A/S and interfacial charge transfer are the two major strategies for overcoming recombination in photocatalysis in this era of nanoparticle composites. Their relationships are considered here. A review of key literature is accompanied by a presentation of three new experiments within the overall aim of assessing the relation of these strategies. The cases presented include: A/S by a high silica zeolite/TiO2 composite, charge transfer (CT between phases in a TiO2/WO3 composite and both A/S and CT by composites of TiO2 with powered activated carbon (AC and single-walled carbon nanotubes (SWCNT. The opportunities presented by the two strategies for moving toward photocatalysts that could support applications for the removal of contaminants from drinking water or that lead to a practical adsorbent for organics that could be regenerated photocatalytically link this discussion to ongoing research here.

  9. Optimal Surface Amino-Functionalization Following Thermo-Alkaline Treatment of Nanostructured Silica Adsorbents for Enhanced CO2 Adsorption

    Directory of Open Access Journals (Sweden)

    Obdulia Medina-Juárez

    2016-11-01

    Full Text Available Special preparation of Santa Barbara Amorphous (SBA-15, mesoporous silica with highly hexagonal ordered, these materials have been carried out for creating adsorbents exhibiting an enhanced and partially selective adsorption toward CO2. This creation starts from an adequate conditioning of the silica surface, via a thermo-alkaline treatment to increase the population of silanol species on it. CO2 adsorption is only reasonably achieved when the SiO2 surface becomes aminated after put in contact with a solution of an amino alkoxide compound in the right solvent. Unfunctionalized and amine-functionalized substrates were characterized through X-ray diffraction, N2 sorption, Raman spectroscopy, electron microscopy, 29Si solid-state Nuclear Magnetic Resonance (NMR, and NH3 thermal programmed desorption. These analyses proved that the thermo-alkaline procedure desilicates the substrate and eliminates the micropores (without affecting the SBA-15 capillaries, present in the original solid. NMR analysis confirms that the hydroxylated solid anchors more amino functionalizing molecules than the unhydroxylated material. The SBA-15 sample subjected to hydroxylation and amino-functionalization displays a high enthalpy of interaction, a reason why this solid is suitable for a strong deposition of CO2 but with the possibility of observing a low-pressure hysteresis phenomenon. Contrastingly, CH4 adsorption on amino-functionalized, hydroxylated SBA-15 substrates becomes almost five times lower than the CO2 one, thus giving proof of their selectivity toward CO2. Although the amount of retained CO2 is not yet similar to or higher than those determined in other investigations, the methodology herein described is still susceptible to optimization.

  10. Optimal Surface Amino-Functionalization Following Thermo-Alkaline Treatment of Nanostructured Silica Adsorbents for Enhanced CO2 Adsorption

    Science.gov (United States)

    Medina-Juárez, Obdulia; García-Sánchez, Miguel Ángel; Arellano-Sánchez, Ulises; Kornhauser-Straus, Isaac; Rojas-González, Fernando

    2016-01-01

    Special preparation of Santa Barbara Amorphous (SBA)-15, mesoporous silica with highly hexagonal ordered, these materials have been carried out for creating adsorbents exhibiting an enhanced and partially selective adsorption toward CO2. This creation starts from an adequate conditioning of the silica surface, via a thermo-alkaline treatment to increase the population of silanol species on it. CO2 adsorption is only reasonably achieved when the SiO2 surface becomes aminated after put in contact with a solution of an amino alkoxide compound in the right solvent. Unfunctionalized and amine-functionalized substrates were characterized through X-ray diffraction, N2 sorption, Raman spectroscopy, electron microscopy, 29Si solid-state Nuclear Magnetic Resonance (NMR), and NH3 thermal programmed desorption. These analyses proved that the thermo-alkaline procedure desilicates the substrate and eliminates the micropores (without affecting the SBA-15 capillaries), present in the original solid. NMR analysis confirms that the hydroxylated solid anchors more amino functionalizing molecules than the unhydroxylated material. The SBA-15 sample subjected to hydroxylation and amino-functionalization displays a high enthalpy of interaction, a reason why this solid is suitable for a strong deposition of CO2 but with the possibility of observing a low-pressure hysteresis phenomenon. Contrastingly, CH4 adsorption on amino-functionalized, hydroxylated SBA-15 substrates becomes almost five times lower than the CO2 one, thus giving proof of their selectivity toward CO2. Although the amount of retained CO2 is not yet similar to or higher than those determined in other investigations, the methodology herein described is still susceptible to optimization. PMID:28774017

  11. Sea-urchin-like iron oxide nanostructures for water treatment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun Uk, E-mail: leeho@kbsi.re.kr [Division of Materials Science, Korea Basic Science Institute, Daejeon 305-333 (Korea, Republic of); Lee, Soon Chang [Department of Fine Chemical Engineering and Applied Chemistry, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Lee, Young-Chul [Department of Biological Engineering, College of Engineering, Inha University, Incheon 402-751 (Korea, Republic of); Vrtnik, Stane; Kim, Changsoo; Lee, SangGap [Division of Materials Science, Korea Basic Science Institute, Daejeon 305-333 (Korea, Republic of); Lee, Young Boo; Nam, Bora [Jeonju Center, Korea Basic Science Institute, Jeonju 561-756 (Korea, Republic of); Lee, Jae Won [Department of Energy Engineering, Dankook University, Cheonan 330-714 (Korea, Republic of); Park, So Young; Lee, Sang Moon [Division of Materials Science, Korea Basic Science Institute, Daejeon 305-333 (Korea, Republic of); Lee, Jouhahn, E-mail: jouhahn@kbsi.re.kr [Division of Materials Science, Korea Basic Science Institute, Daejeon 305-333 (Korea, Republic of)

    2013-11-15

    Highlights: • The u-MFN were synthesized via a ultrasound irradiation and/or calcinations process. • The u-MFN exhibited excellent adsorption capacities. • The u-MFN also displayed excellent adsorption of organic polluent after recycling. • The u-MFN has the potential to be used as an efficient adsorbent material. -- Abstract: To obtain adsorbents with high capacities for removing heavy metals and organic pollutants capable of quick magnetic separation, we fabricated unique sea-urchin-like magnetic iron oxide (mixed γ-Fe{sub 2}O{sub 3}/Fe{sub 3}O{sub 4} phase) nanostructures (called u-MFN) with large surface areas (94.1 m{sup 2} g{sup −1}) and strong magnetic properties (57.9 emu g{sup −1}) using a simple growth process and investigated their potential applications in water treatment. The u-MFN had excellent removal capabilities for the heavy metals As(V) (39.6 mg g{sup −1}) and Cr(VI) (35.0 mg g{sup −1}) and the organic pollutant Congo red (109.2 mg g{sup −1}). The u-MFN also displays excellent adsorption of Congo red after recycling. Because of its high adsorption capacity, fast adsorption rate, and quick magnetic separation from treated water, the u-MFN developed in the present study is expected to be an efficient magnetic adsorbent for heavy metals and organic pollutants in aqueous solutions.

  12. Heat transfer to the adsorbent in solar adsorption cooling device

    Science.gov (United States)

    Pilat, Peter; Patsch, Marek; Papucik, Stefan; Vantuch, Martin

    2014-08-01

    The article deals with design and construction of solar adsorption cooling device and with heat transfer problem in adsorber. The most important part of adsorption cooling system is adsorber/desorber containing adsorbent. Zeolith (adsorbent) type was chosen for its high adsorption capacity, like a coolant was used water. In adsorber/desorber occur, at heating of adsorbent, to heat transfer from heat change medium to the adsorbent. The time required for heating of adsorber filling is very important, because on it depend flexibility of cooling system. Zeolith has a large thermal resistance, therefore it had to be adapted the design and construction of adsorber. As the best shows the tube type of adsorber with double coat construction. By this construction is ensured thin layer of adsorbent and heating is quick in all volume of adsorbent. The process of heat transfer was experimentally measured, but for comparison simulated in ANSYS, too.

  13. Removal and recovery of phosphate from water by calcium-silicate composites-novel adsorbents made from waste glass and shells.

    Science.gov (United States)

    Jiang, Dan; Amano, Yoshimasa; Machida, Motoi

    2017-03-01

    The removal and recovery of phosphate from water by calcium-silicate composite (CSC) and alkali-treated calcium-silicate composite (ASC) was investigated. ASC had a higher specific surface area and total pore volume, and exhibited better performance of phosphate adsorption than CSC. In the batch mode adsorption studies, the isotherm adsorption experiments data fitted well the Langmuir isotherm model and the maximum adsorption capacities were 120 and 73.0 mg/g for ASC and for CSC, respectively. For the kinetic study, the experimental data fitted very well the pseudo-second-order kinetic model. The uptake of phosphate could be performed well over a wide pH range, from 3.0 to 13.0 for ASC and from 4.0 to 13.0 for CSC. The adsorption of phosphate by ASC was very selective even with 10 times higher concentration of other coexistent anions. For the adsorption of low phosphate concentration (10 mg/L), ASC could efficiently remove phosphate at the dosage of 0.8 g/L, while CSC was even difficult to remove phosphate at the dosage of 4.0 g/L. Phosphate fractionation results and FTIR spectra showed that phosphate-Ca complex was formed through phosphate adsorption process. The adsorbed phosphate could be successfully desorbed by 2% citric acid solution, indicating that the adsorbent after adsorbed phosphate could be reusable as fertilizer in the agricultural field.

  14. Adsorptive Removal of Pharmaceuticals and Personal Care Products from Water with Functionalized Metal-organic Frameworks: Remarkable Adsorbents with Hydrogen-bonding Abilities

    Science.gov (United States)

    Seo, Pill Won; Bhadra, Biswa Nath; Ahmed, Imteaz; Khan, Nazmul Abedin; Jhung, Sung Hwa

    2016-10-01

    Adsorption of typical pharmaceuticals and personal care products (PPCPs) (such as naproxen, ibuprofen and oxybenzone) from aqueous solutions was studied by using the highly porous metal-organic framework (MOF) MIL-101 with and without functionalization. Adsorption results showed that MIL-101s with H-donor functional groups such as -OH and -NH2 were very effective for naproxen adsorption, despite a decrease in porosity, probably because of H-bonding between O atoms on naproxen and H atoms on the adsorbent. For this reason, MIL-101 with two functional groups capable of H-bonding (MIL-101-(OH)2) exhibited remarkable adsorption capacity based on adsorbent surface area. The favorable contributions of -OH and -(OH)2 on MIL-101 in the increased adsorption of ibuprofen and oxybenzone (especially based on porosity) confirmed again the importance of H-bonding mechanism. The adsorbent with the highest adsorption capacity, MIL-101-OH, was very competitive when compared with carbonaceous materials, mesoporous materials, and pristine MIL-101. Moreover, the MIL-101-OH could be recycled several times by simply washing with ethanol, suggesting potential application in the adsorptive removal of PPCPs from water.

  15. Nanotechnology for a safe and sustainable water supply: enabling integrated water treatment and reuse.

    Science.gov (United States)

    Qu, Xiaolei; Brame, Jonathon; Li, Qilin; Alvarez, Pedro J J

    2013-03-19

    Ensuring reliable access to clean and affordable water is one of the greatest global challenges of this century. As the world's population increases, water pollution becomes more complex and difficult to remove, and global climate change threatens to exacerbate water scarcity in many areas, the magnitude of this challenge is rapidly increasing. Wastewater reuse is becoming a common necessity, even as a source of potable water, but our separate wastewater collection and water supply systems are not designed to accommodate this pressing need. Furthermore, the aging centralized water and wastewater infrastructure in the developed world faces growing demands to produce higher quality water using less energy and with lower treatment costs. In addition, it is impractical to establish such massive systems in developing regions that currently lack water and wastewater infrastructure. These challenges underscore the need for technological innovation to transform the way we treat, distribute, use, and reuse water toward a distributed, differential water treatment and reuse paradigm (i.e., treat water and wastewater locally only to the required level dictated by the intended use). Nanotechnology offers opportunities to develop next-generation water supply systems. This Account reviews promising nanotechnology-enabled water treatment processes and provides a broad view on how they could transform our water supply and wastewater treatment systems. The extraordinary properties of nanomaterials, such as high surface area, photosensitivity, catalytic and antimicrobial activity, electrochemical, optical, and magnetic properties, and tunable pore size and surface chemistry, provide useful features for many applications. These applications include sensors for water quality monitoring, specialty adsorbents, solar disinfection/decontamination, and high performance membranes. More importantly, the modular, multifunctional and high-efficiency processes enabled by nanotechnology provide a

  16. Underutilized Luffa cylindrica sponge: A local bio-adsorbent for the removal of Pb(II pollutant from water system

    Directory of Open Access Journals (Sweden)

    Adewale Adewuyi

    2017-06-01

    Full Text Available Biosorption of Pb2+ ions from aqueous solution onto Luffa cylindrica sponge as adsorbent (LCSA was investigated in batch adsorption system. LCSA was characterized by X-ray diffraction analysis technique (XRD, Scanning Electron Microscopy (SEM coupled with energy dispersive spectroscopy (EDS, Fourier Transform Infrared spectrometer (FTIR, particle size dispersion, zeta potential, thermogravimetric analysis (TGA, and Brunauer-Emmett-Teller (BET surface area analyzer. The sorption of Pb2+ ions by LCSA was subjected to equilibrium, thermodynamics and kinetic studies and was carried out by considering the effects of pH, initial metal ions concentration, contact time and temperature. BET surface area of LCSA was 6.00 m2/g with mean distribution size of 0.02 µm while the zeta potential was found to increase as the value of pH increased from 4 to 14. The findings revealed the maximum equilibrium adsorption capacity to be 75.853 mg/g. The process is chemisorptive and controlled by intra-particle diffusion. The values of thermodynamic parameters such as ΔG°, ΔH° and ΔS° showed a stable adsorbent-adsorbate (LCSA-Pb configuration which is exothermic. The adsorption capacity of LCSA compared better than some natural bio-sorbent found in literature.

  17. Sequestering Nickel (II Ions from Aqueous Solutions Using Various Adsorbents: A Review

    Directory of Open Access Journals (Sweden)

    Olugbenga Solomon Bello

    2014-06-01

    Full Text Available Adsorption process has proven to be one of the best water treatment technologies around the world and activated carbon is undoubtedly considered as a universal adsorbent for the removal of different types of pollutants from water. However, widespread use of commercial activated carbon is sometimes restricted due to its high cost. Attempts have been made to develop inexpensive adsorbents utilizing numerous agro-industrial and municipal waste materials. Use of agricultural waste materials as low-cost adsorbents is attractive because it reduces the cost of waste disposal, thereby leading to environmental protection. In this review, agricultural, synthetic and other adsorbents used for adsorbing nickel (II ion from aqueous solutions are reported. Different ways to improve their efficiencies are also discussed.

  18. Technology for Water Treatment (National Water Management)

    Science.gov (United States)

    1992-01-01

    The buildup of scale and corrosion is the most costly maintenance problem in cooling tower operation. Jet Propulsion Laboratory successfully developed a non-chemical system that not only curbed scale and corrosion, but also offered advantages in water conservation, cost savings and the elimination of toxic chemical discharge. In the system, ozone is produced by an on-site generator and introduced to the cooling tower water. Organic impurities are oxidized, and the dissolved ozone removes bacteria and scale. National Water Management, a NASA licensee, has installed its ozone advantage systems at some 200 cooling towers. Customers have saved money and eliminated chemical storage and discharge.

  19. FACTORS AFFECTING WATER QUALITY BEFORE TREATMENT

    Directory of Open Access Journals (Sweden)

    Artur Jachimowski

    2017-02-01

    Full Text Available The article assesses the impact of natural and anthropogenic factors on the quality of surface water grasped by Krakow's water treatment plants. We analyzed the indicators chosen in the physicochemical marked in the raw water in the years 2007–2014. The study shows that the water prior to treatment differed in the number and share of separate factors. These components, in turn, explained 63% to 71% of analyzed chemical composition of water.

  20. FACTORS AFFECTING WATER QUALITY BEFORE TREATMENT

    OpenAIRE

    Artur Jachimowski

    2017-01-01

    The article assesses the impact of natural and anthropogenic factors on the quality of surface water grasped by Krakow's water treatment plants. We analyzed the indicators chosen in the physicochemical marked in the raw water in the years 2007–2014. The study shows that the water prior to treatment differed in the number and share of separate factors. These components, in turn, explained 63% to 71% of analyzed chemical composition of water.

  1. TENORM: Drinking Water Treatment Residuals

    Science.gov (United States)

    EPA has specific regulations under the Safe Drinking Water Act (SDWA) that limit the amount of radioactivity allowed in community water systems. Learn about methods used to treat these water supplies to remove radioactivity and manage wastes.

  2. Sn(II) oxy-hydroxides as potential adsorbents for Cr(VI)-uptake from drinking water: An X-ray absorption study

    Energy Technology Data Exchange (ETDEWEB)

    Pinakidou, Fani; Kaprara, Efthimia [Aristotle University of Thessaloniki, School of Chemical Engineering, Analytical Chemistry Laboratory, 54124 Thessaloniki (Greece); Katsikini, Maria; Paloura, Eleni C.; Simeonidis, Konstantinos [Aristotle University of Thessaloniki, School of Physics, Department of Solid State Physics, 54124 Thessaloniki (Greece); Mitrakas, Manassis, E-mail: manasis@eng.auth.gr [Aristotle University of Thessaloniki, School of Chemical Engineering, Analytical Chemistry Laboratory, 54124 Thessaloniki (Greece)

    2016-05-01

    The feasibility of implementing a Sn(II) oxy-hydroxide (Sn{sub 6}O{sub 4}(OH){sub 4}) for the reduction and adsorption of Cr(VI) in drinking water treatment was investigated using XAFS spectroscopies at the Cr-K-edge. The analysis of the Cr-K-edge XANES and EXAFS spectra verified the effective use of Sn{sub 6}O{sub 4}(OH){sub 4} for successful Cr(VI) removal. Adsorption isotherms, as well as dynamic Rapid Small Scale Test (RSSCT) in NSF water matrix showed that Sn{sub 6}O{sub 4}(OH){sub 4} can decrease Cr(VI) concentration below the upcoming regulation limit of 10 μg/L for drinking water. Moreover, an uptake capacity of 7.2 μg/mg at breakthrough concentration of 10 μg/L was estimated from the RSSCT, while the residual Cr(VI) concentration ranged at sub-ppb level for a significant period of the experiment. Furthermore, no evidence for the formation of Cr(OH){sub 3} precipitates was found. On the contrary, Cr(III)-oxyanions were chemisorbed onto SnO{sub 2}, which was formed after Sn(II)-oxidation during Cr(VI)-reduction. Nevertheless, changes in the type of Cr(III)-inner sphere complexes were observed after increasing surface coverage: Cr(III)-oxyanions preferentially sorb in a geometry which combines both bidentate binuclear ({sup 2}C) and monodentate ({sup 1}V) geometries, at the expense of the present bidentate mononuclear ({sup 2}E) contributions. On the other hand, the pH during sorption does not affect the adsorption mechanism of Cr(III)-species. The implementation of Sn{sub 6}O{sub 4}(OH){sub 4} in water treatment technology combines the advantage of rapidly reducing a large amount of Cr(VI) due to donation of two electrons by Sn(II) and also the strong chemisorption of Cr(III) in a combination of the {sup 2}C and {sup 1}V configurations, which enhances the safe disposal of spent adsorbents. - Highlights: • Effective Cr(VI) removal from drinking water by Sn{sub 6}O{sub 4}(OH){sub 4} • Sn{sub 6}O{sub 4}(OH){sub 4} transformation to SnO{sub 2} after Cr

  3. Zeolites as alcohol adsorbents from aqueous solutions

    Directory of Open Access Journals (Sweden)

    Cekova Blagica

    2006-01-01

    Full Text Available The potential usage of zeolites as adsorbents for the removal of organic molecules from water was investigated in a series of experiments with aqueous solutions of lower alcohols. This could represent a simple solution to the problem of cleaning up industrial wastewater as well as recovering valuable chemicals at relatively low costs. Adsorption isotherms of the Langmuir type were applied, and calculations showed that the amount of propanol adsorbed on silicalite corresponded to approximately 70% of the pore volume. The adsorption process is simple, and recovery of the more concentrated products is easily done by heat treatment and/or at lowered pressures. Adsorption experiments with aqueous acetone showed that silicalite had approximately the same adsorption capacity for acetone as for n-propanol. Heats of adsorption were determined calorimetrically.

  4. COMBINATION OF MOLECULAR ADSORBENT RECIRCULATING SYSTEM AND RADIOIODINE FOR THE TREATMENT OF CONCURRENT HYPERTHYROIDISM AND SEVERE LIVER DYSFUNCTION: A RETROSPECTIVE COHORT STUDY.

    Science.gov (United States)

    Zhang, Qing; Guan, Yanxing; Xiang, Tianxin; Liu, Shaozheng; Chen, Qingjie; Zhang, Qing

    2017-02-01

    The treatment of hyperthyroidism associated with severe liver dysfunction (LD) is a clinical challenge, and there has been no unified examination of this problem. The objective of this study was to assess the efficacy and safety of radioiodine (131I) in combination with a molecular adsorbent recirculating system (MARS) for the treatment of hyperthyroidism complicated by severe liver LD. A total of 116 hyperthyroidism patients with concomitant LD who received MARS treatment were studied retrospectively. The patients were grouped according to whether or not they also received 131I treatment: Group 1 (59 patients) received 131I following MARS treatment, while Group 2 (57 cases) received only MARS. Clinical outcomes, including thyroid hormone levels, liver function parameters, and therapeutic efficacy were calculated. The overall response rate was significantly greater in Group 1 than in Group 2 (Phyperthyroidism complicated by severe LD was effective and safe. The use of this system could rapidly improve liver function and metabolism, allowing 131I therapy to be applied as early as possible with a shortened recovery time of liver function. ALSS = artificial liver support system ALT = alanine transaminase AST = aspartate transaminase ATD = antithyroid drugs DBil = direct bilirubin FT3 = free tri-iodothyronine FT4 = free thyroxine 131I = radioiodine INR = international normalized ratio LD = liver dysfunction MARS = molecular adsorbent recirculating system MELD = model for end-stage liver disease PT = prothrombin time TBil = total bilirubin TSH = thyroid-stimulating hormone.

  5. Sum Frequency Generation Vibrational Spectroscopy of Adsorbed Amino Acids, Peptides and Proteins of Hydrophilic and Hydrophobic Solid-Water Interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Holinga IV, George Joseph [Univ. of California, Berkeley, CA (United States)

    2010-09-01

    Sum frequency generation (SFG) vibrational spectroscopy was used to investigate the interfacial properties of several amino acids, peptides, and proteins adsorbed at the hydrophilic polystyrene solid-liquid and the hydrophobic silica solid-liquid interfaces. The influence of experimental geometry on the sensitivity and resolution of the SFG vibrational spectroscopy technique was investigated both theoretically and experimentally. SFG was implemented to investigate the adsorption and organization of eight individual amino acids at model hydrophilic and hydrophobic surfaces under physiological conditions. Biointerface studies were conducted using a combination of SFG and quartz crystal microbalance (QCM) comparing the interfacial structure and concentration of two amino acids and their corresponding homopeptides at two model liquid-solid interfaces as a function of their concentration in aqueous solutions. The influence of temperature, concentration, equilibration time, and electrical bias on the extent of adsorption and interfacial structure of biomolecules were explored at the liquid-solid interface via QCM and SFG. QCM was utilized to quantify the biological activity of heparin functionalized surfaces. A novel optical parametric amplifier was developed and utilized in SFG experiments to investigate the secondary structure of an adsorbed model peptide at the solid-liquid interface.

  6. Evaluation of the use of performance reference compounds in an Oasis-HLB adsorbent based passive sampler for improving water concentration estimates of polar herbicides in freshwater.

    Science.gov (United States)

    Mazzella, Nicolas; Lissalde, Sophie; Moreira, Sylvia; Delmas, François; Mazellier, Patrick; Huckins, James N

    2010-03-01

    Passive samplers such as the Polar Organic Chemical Integrative Sampler (POCIS) are useful tools for monitoring trace levels of polar organic chemicals in aquatic environments. The use of performance reference compounds (PRC) spiked into the POCIS adsorbent for in situ calibration may improve the semiquantitative nature of water concentration estimates based on this type of sampler. In this work, deuterium labeled atrazine-desisopropyl (DIA-d5) was chosen as PRC because of its relatively high fugacity from Oasis HLB (the POCIS adsorbent used) and our earlier evidence of its isotropic exchange. In situ calibration of POCIS spiked with DIA-d5 was performed, and the resulting time-weighted average concentration estimates were compared with similar values from an automatic sampler equipped with Oasis HLB cartridges. Before PRC correction, water concentration estimates based on POCIS data sampling rates from a laboratory calibration exposure were systematically lower than the reference concentrations obtained with the automatic sampler. Use of the DIA-d5 PRC data to correct POCIS sampling rates narrowed differences between corresponding values derived from the two methods. Application of PRCs for in situ calibration seems promising for improving POCIS-derived concentration estimates of polar pesticides. However, careful attention must be paid to the minimization of matrix effects when the quantification is performed by HPLC-ESI-MS/MS.

  7. Water Treatment Technology - General Plant Operation.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on general plant operations provides instructional materials for seven competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: water supply regulations, water plant…

  8. Surface Water Treatment Rules State Implementation Guidance

    Science.gov (United States)

    These documents provide guidance to states, tribes and U.S. EPA Regions exercising primary enforcement responsibility under the Safe Drinking Water Act. The documents contain EPA’s recommendations for implementation of the Surface Water Treatment Rules.

  9. A novel fiber-based adsorbent technology

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, T.A. [Chemica Technologies, Inc., Bend, OR (United States)

    1997-10-01

    In this Phase I Small Business Innovation Research program, Chemica Technologies, Inc. is developing an economical, robust, fiber-based adsorbent technology for removal of heavy metals from contaminated water. The key innovation is the development of regenerable adsorbent fibers and adsorbent fiber cloths that have high capacity and selectivity for heavy metals and are chemically robust. The process has the potential for widespread use at DOE facilities, mining operations, and the chemical process industry.

  10. Comparison and evaluation of five types of imidazole-modified silica adsorbents for the removal of 2,4-dinitrophenol from water samples with the methyl group at different positions of imidazolium ring

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhike, E-mail: wzk@htu.cn; Ye, Cunling; Li, Juan; Wang, Heping; Zhang, Han

    2013-09-15

    Highlights: • Five imidazole-modified silica adsorbents were synthesized. • The five adsorbents are of primary anion-exchange and electrostatic nature. • The electrostatic nature was affected by the methyl group of imidazolium ring. • The five adsorbents are suitable for adsorption of 2,4-DNP with low pK{sub a} value. • The adsorbent was regenerated and reused ten times by washings with HCl and water. -- Abstract: The objective of this work was to improve the understanding the influence of the methyl group at different positions of imidazolium ring on the adsorption behaviors of imidazole-modified silica adsorbents. Five adsorbents named as SilprImCl, SilprM{sub 1}ImCl, SilprM{sub 2}ImCl, SilprM{sub 4}ImCl and SilprM{sub 1}M{sub 2}ImCl were synthesized using imidazole, 1-methylimidazole, 2-methylimidazole, 4-methylimidazole and 1,2-dimethylimidazole, respectively. These adsorbents were characterized by scanning electron microscope, infrared spectra, thermogravimetric analysis, elemental analysis and BET analysis. Firstly, phenol, 2-nitrophenol (2-NP), 3-nitrophenol (3-NP), 4-nitrophenol (4-NP) and 2,4-dinitrophenol (2,4-DNP) were used as adsorbates to investigate the selectivity of SilprImCl and its adsorption capacities followed the order of 2,4-DNP ≫ 4-NP > 2-NP ≫ 3-NP > phenol. Therefore, 2,4-DNP was used to investigate the adsorption behaviors of the five adsorbents. It was inferred that the adsorbents are of primary anion-exchange and electrostatic nature. The electrostatic nature was affected significantly by the methyl group at different positions of imidazolium ring. The adsorbed amounts of 2,4-DNP decreased in the order of: SilprM{sub 1}M{sub 2}ImCl ≈ SilprM{sub 1}ImCl > SilprM{sub 4}ImCl > SilprM{sub 2}ImCl > SilprImCl. The adsorption–elution experiments indicated that 2,4-DNP can be removed from aqueous solutions by a SilprM{sub 4}ImCl packed column and the recovery of 91.6% was obtained. The adsorbent could be regenerated and reused

  11. Comparative study of adsorbents for the removal of fluoride ions from water use and consumption in Mexico; Estudio comparativo de adsorbentes para la remocion de iones fluoruro del agua de uso y consumo en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Teutli S, E. A.

    2014-07-01

    Although fluoride is essential for health many studies have shown it is associated with some health problems, such as fluoro sis, thyroid disorder, neurological disease, Alzheimer, pineal gland and cancer. One of the major routes of exposure is through drinking water. The World Health Organization (Who) allows only 1.5 mg/L as a safe limit for fluoride ions in drinking water and the EPA U. S. Environmental Protection Agency has recently proposed 0.7 mg/L. In some cases, the water extracted from deep wells has concentrations of fluoride ions above 1.5 mg/L (NOM-127-SSA1-2000) which is the permissible limit of water for human use and consumption (whuc). In several countries, there are high concentrations of fluoride ions due to the geological distribution of fluorine-rich rocks. In our country we can find several states that have concentrations higher than 1.5 mg/L of fluoride ions in water, such as Aguascalientes, Zacatecas, Chihuahua, Coahuila, Durango, Guanajuato, Sonora, Jalisco and San Luis Potosi. Various technologies have been proposed to remove fluoride ions from water, such as adsorption, ion exchange, reverse osmosis, nano filtration, electrodialysis, dialysis and electrocoagulation. Sorption is superior to other techniques in terms of initial cost, simplicity of design and ease of operation. In this work systematic studies were done considering the aspects mentioned above, in order to determine the adsorbents properties and most suitable conditions for the removal of fluoride ions from whuc. It is important to note that to date no adsorption treatments for the removal of fluoride ions from water for human use and consumption in our country is done, although there are established methodologies, they have not been implemented because of their high costs. In this work an integral study was done on the removal of fluoride ions from water for human use and consumption. A comparative study of hematite, calcite and zeolite as adsorbents was performed to develop a

  12. MWH's water treatment: principles and design

    National Research Council Canada - National Science Library

    Crittenden, John C

    2012-01-01

    ... with additional worked problems and new treatment approaches. It covers both the principles and theory of water treatment as well as the practical considerations of plant design and distribution...

  13. Crow Nation Water Treatment Plant NPDES Permit

    Science.gov (United States)

    Under NPDES permit MT-0030538, the U.S. Bureau of Indian Affairs is authorized to discharge from the Crow Agency water treatment plants via the wastewater treatment facility located in Bighorn County, Montana to the Little Bighorn River.

  14. Water/carbonate stripping for CO.sub.2 capture adsorber regeneration and CO.sub.2 delivery to photoautotrophs

    Science.gov (United States)

    Chance, Ronald; Koros, William J.; McCool, Benjamin; Noel, James

    2015-08-11

    The invention provides systems and methods for the delivery of carbon to photoautotrophs. The invention utilizes low energy regeneration of adsorbent for CO.sub.2 capture and provides for effective CO.sub.2 loading into liquids useful for photoautotroph growth and/or production of photosynthetic products, such as biofuels, via photoautotrophic culture media. The inventive system comprises a fluid/membrane/fluid contactor that provides selective transfer of molecular CO.sub.2 via a dense (non-porous) membrane from a carbonate-based CO.sub.2 snipping solution to a culture medium where the CO.sub.2 is consumed by a photoautotroph for the production of biofuels, biofuel precursors or other commercial products.

  15. Sustainable treatment of municipal waste water

    DEFF Research Database (Denmark)

    Hansen, Peter Augusto; Larsen, Henrik Fred

    The main goal of the EU FP6 NEPTUNE program is to develop new and improve existing waste water treatment technologies (WWTT) and sludge handling technologies for municipal waste water, in accordance with the concepts behind the EU Water Framework Directive. As part of this work, the project.......e. heavy metals, pharmaceuticals and endocrine disruptors) in the waste water. As a novel approach, the potential ecotoxicity and human toxicity impacts from a high number of micropollutants and the potential impacts from pathogens will be included. In total, more that 20 different waste water and sludge...... treatment technologies are to be assessed. This paper will present the first LCA results from running existing life cycle impact assessment (LCIA) methodology on some of the waste water treatment technologies. Keywords: Sustainability, LCA, micropollutants, waste water treatment technologies....

  16. Bicarbonate Elution of Uranium from Amidoxime-Based Polymer Adsorbents for Sequestering Uranium from Seawater

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Horng-Bin [Department of Chemistry, University of Idaho, Moscow, Idaho 83844 USA; Wai, Chien M. [Department of Chemistry, University of Idaho, Moscow, Idaho 83844 USA; Kuo, Li-Jung [Pacific Northwest National Laboratory, Marine Sciences Laboratory, Sequim, Washington 98382 USA; Gill, Gary [Pacific Northwest National Laboratory, Marine Sciences Laboratory, Sequim, Washington 98382 USA; Tian, Guoxin [Lawrence Berkeley National Laboratory, Berkeley, California 94720 USA; Rao, Linfeng [Lawrence Berkeley National Laboratory, Berkeley, California 94720 USA; Das, Sadananda [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 USA; Mayes, Richard T. [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 USA; Janke, Christopher J. [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 USA

    2017-05-02

    Uranium adsorbed on amidoxime-based polyethylene fibers in simulated seawater can be quantitatively eluted using 3 M KHCO3 at 40°C. Thermodynamic calculations are in agreement with the experimental observation that at high bicarbonate concentrations (3 M) uranyl ions bound to amidoxime molecules are converted to uranyl tris-carbonato complex in the aqueous solution. The elution process is basically the reverse reaction of the uranium adsorption process which occurs at a very low bicarbonate concentration (~10-3 M) in seawater. In real seawater experiments, the bicarbonate elution is followed by a NaOH treatment to remove natural organic matter adsorbed on the polymer adsorbent. Using the sequential bicarbonate and NaOH elution, the adsorbent is reusable after rinsing with deionized water and the recycled adsorbent shows no loss of uranium loading capacity based on real seawater experiments.

  17. Establishing Solar Water Disinfection as a water treatment method at ...

    African Journals Online (AJOL)

    1.1 billion People worldwide do not have access to safe drinking water and therefore are exposed to a high risk for diarrhoeal diseases. As a consequence, about 6,000 children die each day of dehydration due to diarrhoea. Adequate water treatment methods and safe storage of drinking water, combined with hygiene ...

  18. Cyclic process of simazine removal from waters by adsorption on zeolite H-Y and its regeneration by thermal treatment

    Energy Technology Data Exchange (ETDEWEB)

    Sannino, Filomena, E-mail: fsannino@unina.it [Dipartimento di Scienze del Suolo, della Pianta, dell' Ambiente e delle Produzioni Animali, Universita di Napoli ' Federico II' , Via Universita 100, 80055 Portici (Italy); Ruocco, Silvia [Dipartimento di Scienze del Suolo, della Pianta, dell' Ambiente e delle Produzioni Animali, Universita di Napoli ' Federico II' , Via Universita 100, 80055 Portici (Italy); Marocco, Antonello; Esposito, Serena; Pansini, Michele [Laboratorio Materiali - Dipartimento di Meccanica, Strutture, Ambiente e Territorio - Universita di Cassino - Via Di Biasio 43 - 03043 Cassino (Italy)

    2012-08-30

    Highlights: Black-Right-Pointing-Pointer Bringing agrochemical concentration below the law limit allowed in wastewaters. Black-Right-Pointing-Pointer Regenerating the adsorbent which can be used again in the cyclic process. Black-Right-Pointing-Pointer Destroying the agrochemical molecules by combustion. - Abstract: Removal of the agrochemical simazine from polluted waters through adsorption by zeolite Y in its protonic form was studied. The investigated parameters were: pH, time, initial simazine concentration and solid/liquid ratio. An iterative process of simazine removal from waters is proposed, featuring: (i) final agrochemical concentration well below 0.05 mg/dm{sup 3}, the maximum concentration allowed by Italian laws in wastewaters; (ii) regeneration of the adsorbent by a few minutes thermal treatment in air at about 500 Degree-Sign C, which results in the combustion of simazine without damage of the adsorbent; (iii) destruction of the agrochemical compound by combustion.

  19. Removing heavy metals using permeable pavement system with a titanate nano-fibrous adsorbent column as a post treatment.

    Science.gov (United States)

    Sounthararajah, Danious Pratheep; Loganathan, Paripurnanda; Kandasamy, Jayakumar; Vigneswaran, Saravanamuthu

    2017-02-01

    Permeable pavement systems (PPS) are a widely-used treatment measure in sustainable stormwater management and groundwater recharge. However, PPS are not very efficient in removing heavy metals from stormwater. A pilot scale study using zeolite or basalt as bed material in PPS removed 41-72%, 67-74%, 38-43%, 61-72%, 63-73% of Cd, Cu, Ni, Pb, and Zn, respectively, from synthetic stormwater (pH 6.5; Cd, Cu, Ni, Pb, and Zn concentrations of 0.04, 0.6, 0.06, 1.0, and 2.0 mg L-1, respectively) over a period of 80 h. The total volume of stormwater that passed through the PPS was equivalent to runoff in 10 years of rainfall in Sydney, Australia. The concentrations of metals in the PPS effluent failed fresh and marine water quality trigger values recommended in the Australian and New Zealand guidelines. An addition of a post-treatment of a horizontal filter column containing a titanate nano-fibrous (TNF) material with a weight  basalt; Pb > Cu > Cd, Ni, Zn. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Purification treatment for underground water

    Energy Technology Data Exchange (ETDEWEB)

    Fonbershteyn, V.

    1985-08-01

    In order for underground water to be clean and to taste good, iron can be removed from it right underground, in the water-bearing stratum, before it is brought to the surface. G.M. Kommunar, V.S. Alekseyev, and V.T. Grebennikov, candidates of technical sciences and associates of the Moscow All-Union Hydrogeology Scientific Research Institute, developed the practical application of this beneficial technology, which makes it possible to do away with purification installations. With the new technology (Patent No. 985 214, 1 018 918) water saturated with oxygen is sent through an ejector and then pumped into a well. It passes through rocks that serve as a natural filter, and the filter is loaded with oxygen. The filter now becomes a barrier for mineral impurities contained in the artesian water. The amount of time needed to pump the oxidized water into the well is calculated beforehand, knowing the capacity of the water-bearing stratum, the porosity of the rocks, the expenditure of pumped oxidized water, and the radius of the zone of the filtering rocks. While the water is pumped out of the well, its properties are monitored periodically. If the concentration of iron exceeds the allowable norm-0.3 mg per liter-the extraction is halted, and oxidized water is once again pumped into the well. It is convenient and economical to combine several wells into one system, where each well will pump and accept water according to its own schedule. This new technology can also be used to remove manganese, heavy metals, and hydrogen sulfide from underground water.

  1. Investigations on humic acid removal from water using surfactant-modified zeolite as adsorbent in a fixed-bed reactor

    Science.gov (United States)

    Elsheikh, Awad F.; Ahmad, Umi Kalthom; Ramli, Zainab

    2017-10-01

    Natural organic matter (NOM) is ubiquitous in aquatic environments and has recently become an issue of worldwide concern in drinking water treatment. The major component of NOM is humic acids (HA). In this study, a natural zeolite (mordenite) was modified employing hexadecyltrimethylammonium bromide (HDTMA) to enhance greater efficient sites for sorption of HA. The natural zeolite and surfactant-modified zeolite (SMZ) were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectrometer (FT-IR), N2 Adsorption-desorption isotherms and BET-specific surface area, thermographic analysis, derivative thermographic analysis (TGA-DTA) and Field emission scanning electron microscopy (FESEM). A fixed-bed reactor was used for the removal of HA and the effects of different experimental parameters such as HDTMA loading levels, HA solution flow rate, solution pH and eluent concentration were investigated. The results indicated that the SMZ bed with HDTMA loading of 75% of external cation exchange capacity (ECEC) at a flow rate of 2 BV/h and pH of 10 showed the greatest enhanced removal efficiency of HA while ethanol solutions (25%v/v) with feed flow rate of 2 BV/h were sufficient for complete regeneration of SMZ and desorption of HA. Measurements of surface area of SMZ indicated that a monolayer formation of the surfactant at those conditions allowed the optimum removal of HA.

  2. Bamboo charcoal as adsorbent for SPE coupled with monolithic column-HPLC for rapid determination of 16 polycyclic aromatic hydrocarbons in water samples.

    Science.gov (United States)

    Ma, Jiping; Li, Mo; Li, Jinhua; Rui, Cuijie; Xin, Yanping; Xue, Qinzhao; Chen, Lingxin

    2011-10-01

    The coupling of solid-phase extraction (SPE) using bamboo charcoal (BC) as an adsorbent with a monolithic column-high performance liquid chromatography (MC-HPLC) method was developed for the high-efficiency enrichment and rapid determination of 16 polycyclic aromatic hydrocarbons (PAHs) in water. Key influence factors, such as the type and the volume of the elution solvent, and the flow rate and the volume of the sample loading, were optimized to obtain a high SPE recovery and extraction efficiency. BC as an SPE adsorbent presented a high extraction efficiency due to its large specific surface area and high adsorption capacity; MC as an HPLC column accelerated the separation within 8 min because of its high porosity, fast mass transfer, and low-pressure resistance. The calibration curves for the PAHs extracted were linear in the range of 0.2-15 µg/L, with the correlation coefficients (r(2)) between 0.9970-0.9999. This method attained good precisions (relative standard deviation, RSD) from 3.5 to 10.9% for the standard PAHs I aqueous solutions at 5 µg/L; the method recoveries ranged in 52.6-121.6% for real spiked river water samples with 0.4 and 4 µg/L. The limits of detection (LODs, S/N = 3) of the method were determined from 11 and 87 ng/L. The developed method was demonstrated to be applicable for the rapid and sensitive determination of 16 PAHs in real environmental water samples.

  3. Household Water Treatments in Developing Countries

    Science.gov (United States)

    Smieja, Joanne A.

    2011-01-01

    Household water treatments (HWT) can help provide clean water to millions of people worldwide who do not have access to safe water. This article describes four common HWT used in developing countries and the pertinent chemistry involved. The intent of this article is to inform both high school and college chemical educators and chemistry students…

  4. Off shore produced water treatment with pertraction

    NARCIS (Netherlands)

    Klaassen, R.

    2004-01-01

    During the production of oil and gas also water is produced. This produced water contains dispersed and dissolved oil components. The impact of offshore emissions of produced water on the environment and the treatment of technologies for it are currently under discussion. Emission limits tend to

  5. Grey water treatment systems: A review

    NARCIS (Netherlands)

    Abu-Ghunmi, L.N.A.H.; Zeeman, G.; Fayyad, M.; Lier, van J.B.

    2011-01-01

    This review aims to discern a treatment for grey water by examining grey water characteristics, reuse standards, technology performance and costs. The review reveals that the systems for treating grey water, whatever its quality, should consist of processes that are able to trap pollutants with a

  6. Effect of the adsorbate (Bromacil) equilibrium concentration in water on its adsorption on powdered activated carbon. Part 2: Kinetic parameters.

    Science.gov (United States)

    Al Mardini, Fadi; Legube, Bernard

    2009-10-30

    The application of several monosolute equilibrium models has previously shown that Bromacil adsorption on SA-UF (Norit) powdered activated carbon (PAC) is probably effective on two types of sites. High reactivity sites were found to be 10-20 less present in a carbon surface than lower reactivity sites, according to the q(m) values calculated by isotherm models. The aims of this work were trying, primarily, to identify the kinetic-determinant stage of the sorption of Bromacil at a wide range of initial pesticide concentrations (approximately 5 to approximately 500 microg L(-1) at pH 7.8), and secondly, to specify the rate constants and other useful design parameters for the application in water treatment. It was therefore not possible to specify a priori whether the diffusion or surface reaction is the key step. It shows that many of the tested models which describe the stage of distribution or the surface reaction are correctly applied. However, the diffusivity values (D and D(0)) were found to be constant only constants for some specific experimental concentrations. The HSDM model of surface diffusion in pores was also applied but the values of the diffusion coefficient of surface (D(s)) were widely scattered and reduce significantly with the initial concentration or the equilibrium concentration in Bromacil. The model of surface reaction of pseudo-second order fitted particularly well and led to constant values which are independent of the equilibrium concentration, except for the low concentrations where the constants become significantly more important. This last observation confirms perfectly the hypothesis based on two types of sites as concluded by the equilibrium data (part 1).

  7. Successful use of the Molecular Adsorbent Recirculating System (MARS) in a patient with primary biliary cirrhosis (PBC) and treatment refractory pruritus.

    Science.gov (United States)

    Mullhaupt, Beat; Kullak-Ublick, Gerd A.; Ambühl, Patrice M.; Stocker, Reto; Renner, Eberhard L.

    2003-04-01

    Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease often associated with severe pruritus. Despite maximal medical management pruritus often persists and has a detrimental effect on quality of life. For patients that are refractory to all medical treatments, more invasive approaches have been tried. Recently, a new extracorporeal hemodiafiltration method, Molecular Adsorbent Recirculating System (MARS), has been described. Based on the hypothesis that hydrophobic, protein-bound metabolites play a major role in the development of liver failure, this device uses an albumin enriched dialysate to facilitate the removal of albumin bound toxins. AIM: To assess the safety and efficacy of a single MARS treatment on the pruritus score in a patient with PBC and treatment refractory pruritus. DESIGN/PATIENTS: A 61-year-old female patient with biopsy proven PBC, who had been accepted on our liver transplantation waiting list because of treatment refractory pruritus, was subjected to a single MARS treatment. RESULTS: At the end of a single 8 h MARS treatment session pruritus completely disappeared. Not unexpectedly, however, this effect was only short lived. Except for a slight hypercalcemia no adverse events were observed. CONCLUSION: A single MARS treatment very effectively improved pruritus. Long-term repetitive treatment, however, might be necessary to sustain its effectiveness.

  8. Catalytic membrane reactor for water and wastewater treatment

    Science.gov (United States)

    Heng, Samuel

    A double membrane reactor was fabricated and assessed for continuous treatment of water containing organic contaminants by ozonation. This innovative reactor consisted of a zeolite membrane prepared on the inner surface of a porous a-alumina support, which served as water selective extractor and active contactor, and a porous stainless membrane which was the ozone gas diffuser. The coupling of membrane separation and chemical oxidation was found to be highly beneficial to both processes. The total organic carbon (TOC) removal rate at the retentate was enhanced by up to 2.2 times, as compared to membrane ozonation. Simultaneously, clean water (membrane support, was shown to further enhance TOC degradation, permeated TOC concentration, permeate flux, and moreover, ozone yield. The achievements of this project included: (1) The development of a novel low-temperature zeolite membrane activation method that generates consistently high quality membranes (i.e. high reproducibility and fewer defects). (2) The demonstration that gamma-alumina and gamma-alumina supported catalysts do not have significant activity and that the TOC removal enhancement usually observed during catalytic ozonation was due primarily to the contribution of adsorption and metal leaching. Thermogravimetric analysis (TGA) and elemental analysis (EA) of the spent catalyst showed that, during catalytic ozonation, oxygenated by-products of increased adsorbability were concentrated onto the gamma-alumina contactor, and were subsequently degraded. (3) The development of a method for coating high surface area gamma-alumina layers onto the grains of zeolite membrane support used as the active membrane contactor.

  9. A Primer on Waste Water Treatment.

    Science.gov (United States)

    Department of the Interior, Washington, DC. Federal Water Pollution Control Administration.

    This information pamphlet is for teachers, students, or the general public concerned with the types of waste water treatment systems, the need for further treatment, and advanced methods of treating wastes. Present day pollution control methods utilizing primary and secondary waste treatment plants, lagoons, and septic tanks are described,…

  10. Coconut-based biosorbents for water treatment--a review of the recent literature.

    Science.gov (United States)

    Bhatnagar, Amit; Vilar, Vítor J P; Botelho, Cidália M S; Boaventura, Rui A R

    2010-10-15

    Biosorption is an emerging technique for water treatment utilizing abundantly available biomaterials (especially agricultural wastes). Among several agricultural wastes studied as biosorbents for water treatment, coconut has been of great importance as various parts of this tree (e.g. coir, shell, etc.) have been extensively studied as biosorbents for the removal of diverse type of pollutants from water. Coconut-based agricultural wastes have gained wide attention as effective biosorbents due to low-cost and significant adsorption potential for the removal of various aquatic pollutants. In this review, an extensive list of coconut-based biosorbents from vast literature has been compiled and their adsorption capacities for various aquatic pollutants as available in the literature are presented. Available abundantly, high biosorption capacity, cost-effectiveness and renewability are the important factors making these materials as economical alternatives for water treatment and waste remediation. This paper presents a state of the art review of coconut-based biosorbents used for water pollution control, highlighting and discussing key advancement on the preparation of novel adsorbents utilizing coconut wastes, its major challenges together with the future prospective. It is evident from the literature survey that coconut-based biosorbents have shown good potential for the removal of various aquatic pollutants. However, still there is a need to find out the practical utility of such developed adsorbents on commercial scale, leading to the superior improvement of pollution control and environmental preservation. Copyright © 2010 Elsevier B.V. All rights reserved.

  11. MEMBRANES FOR DRINKING WATER TREATMENT

    Science.gov (United States)

    Various treatment technologies have proven effective in controlling halogenated disinfection by-products such as precursor removal and the use of alternative disinfectants. One of the most promising methods for halogenated by-product control includes removal of precursors before ...

  12. Natural radioactivity in drinking underground waters in Upper Silesia and solid wastes produced during treatment.

    Science.gov (United States)

    Chmielewska, Izabela; Chałupnik, Stanisław; Bonczyk, Michal

    2014-11-01

    Content of (226)Ra, (228)Ra and uranium isotopes in waters from subsurface aquifers was studied. The sampling points were chosen for having the elevated natural content of iron and manganese. Measurements of radium were made by LSC, while uranium was measured by alpha spectrometry. Waste sludge was measured by gamma spectrometry and three-stage BCR sequential extraction was performed. Radon activity concentration in the air at water treatment plants was determined and dose adsorbed by staff was calculated. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Studies on competitive adsorption of dyes onto carbon (XC-72) and regeneration of adsorbent.

    Science.gov (United States)

    Xing, Xiang; Qu, Hongxia; Chen, Peng; Chi, Bin; Xie, Huifang

    2016-11-01

    Carbon as an adsorbent has been widely studied for wastewater treatment, but the regeneration of adsorbent has been scarcely reported. In this paper, an economical and environmental method was applied to regenerate carbon (XC-72). Results showed that both anhydrous ethanol and deionized water did not obtain optimal effect for the desorption of Acid Orange 7, Ponceau 2R and Rhodamine B, but the desorption effect was dramatically improved when anhydrous ethanol and deionized water were mixed in a certain volume ratio. In addition, the adsorption kinetics of the three dyes were investigated, which showed that the process of adsorption could be well represented by the pseudo-second-order model. For the study of competitive adsorption, this indicated that the interaction between adsorbent and adsorbate had something to do with electrostatic attraction.

  14. Successful treatment of an adult with Amanita phalloides-induced fulminant liver failure with molecular adsorbent recirculating system (MARS).

    Science.gov (United States)

    Lionte, Cătălina; Sorodoc, Laurenţiu; Simionescu, Victoriţa

    2005-09-01

    Despite significant advances in intensive care management of Amanita phalloides-induced fulminant liver failure (FLF), patients with this condition still have a high mortality rate in the absence of orthotopic liver transplantation. Molecular Adsorbent Recirculating System (MARS) is a new, cell-free, extracorporeal liver assistance method utilizing an albumin dialysate for the removal of albumin-bound toxins, and a highly effective depurative therapy in adults with wild mushroom-induced FLF. We report the case of a 39 year old woman with Amanita phalloides-induced FLF, admitted to our intensive care unit (ICU) and treated with MARS. Our patient had severe hepatic dysfunction: hepatic encephalopathy (grade II), ALT = 5022 (2475-10098) IU/L, bilirubin = 7.18 (4.8-10.1) mg/dL, prothrombin time (PT) = 90.4 (29.3-140.4) s. MARS sessions had an immediate impact on liver tests: statistically significant decrease in ammonia, ALT and PT. Hepatic encephalopathy was successfully reduced. The patient survived and the hepatic function completely recovered. MARS appears to be a safe and highly effective depurative therapy in adults with Amanita phalloides-induced FLF.

  15. Experience of Treatments of Amanita phalloides-Induced Fulminant Liver Failure with Molecular Adsorbent Recirculating System and Therapeutic Plasma Exchange.

    Science.gov (United States)

    Zhang, Jicheng; Zhang, Ying; Peng, Zhiyong; Maberry, Donald; Feng, Xueqiang; Bian, Pengfei; Ma, Wenjuan; Wang, Chunting; Qin, Chengyong

    2014-01-01

    Ingestion of the mushroom containing Amanita phalloides can induce fulminant liver failure and death. There are no specific antidotes. Blood purifications, such as molecular adsorbent recirculating system (MARS) and therapeutic plasma exchange (TPE), are potential therapies. However, the extent to which these technologies avert the deleterious effects of amatoxins remains controversial; the optimal intensity, duration, and initiation criteria have not been determined yet. This study aimed to retrospectively observe the effects of MARS and TPE on nine patients with A. phalloides-induced fulminant liver failure. The survival rate for the nine patients was 66.7%. Both TPE and MARS might remove toxins and improve liver functions. However, a single session of TPE produced immediately greater improvements in alanine aminotransferase (-60% vs. -16.3%), aspartate aminotransferase (-47.6% vs. -15.4%), and total bilirubin (-37.3% vs. -17.1%) (compared with the values of pretreatment, all p < 0.05) than MARS compared with MARS. Early intervention may be more effective than delayed therapy. Additionally, the presence of severe liver failure and renal failure indicated worse outcome. Although these findings are promising, additional case-controlled, randomized studies are required to confirm our results.

  16. Photophysical studies of a new water soluble indocarbocyanine dye adsorbed onto microcrystalline cellulose and β-cyclodextrin

    National Research Council Canada - National Science Library

    El-Shishtawy, Reda M; Oliveira, Anabela S; Almeida, Paulo; Ferreira, Diana P; Conceição, David S; Ferreira, Luis F Vieira

    2013-01-01

    A water-soluble indocarbocyanine dye was synthesized and its photophysics were studied for the first time on two solid hosts, microcrystalline cellulose and b-cyclodextrin, as well as in homogeneous media...

  17. Photophysical Studies of a New Water Soluble Indocarbocyanine Dye Adsorbed onto Microcrystalline Cellulose and b-Cyclodextrin

    National Research Council Canada - National Science Library

    Luis F. Vieira Ferreira; Diana P. Ferreira; David S. Conceição; Paulo Almeida; Anabela S. Oliveira; Reda M. El-Shishtawy

    2013-01-01

    A water-soluble indocarbocyanine dye was synthesized and its photophysics were studied for the first time on two solid hosts, microcrystalline cellulose and b-cyclodextrin, as well as in homogeneous media...

  18. Interim Enhanced Surface Water Treatment Rule Documents

    Science.gov (United States)

    The IESWTR balances the need for treatment with potential increases in disinfection by -products. The materials found on this page are intended to assist public water systems and state in the implementation of the IESWTR.

  19. Water/Wastewater Treatment Plant Operator Qualifications.

    Science.gov (United States)

    Water and Sewage Works, 1979

    1979-01-01

    This article summarizes in tabular form the U.S. and Canadian programs for classification of water and wastewater treatment plant personnel. Included are main characteristics of the programs, educational and experience requirements, and indications of requirement substitutions. (CS)

  20. Nanotechnology for water treatment and purification

    CERN Document Server

    Apblett, Allen

    2014-01-01

    This book describes the latest progress in the application of nanotechnology for water treatment and purification. Leaders in the field present both the fundamental science and a comprehensive overview of the diverse range of tools and technologies that have been developed in this critical area. Expert chapters present the unique physicochemical and surface properties of nanoparticles and the advantages that these provide for engineering applications that ensure a supply of safe drinking water for our growing population. Application areas include generating fresh water from seawater, preventing contamination of the environment, and creating effective and efficient methods for remediation of polluted waters. The chapter authors are leading world-wide experts in the field with either academic or industrial experience, ensuring that this comprehensive volume presents the state-of-the-art in the integration of nanotechnology with water treatment and purification. Covers both wastewater and drinking water treatmen...

  1. Assessment of carbon nanotubes and silver nanoparticles loaded clays as adsorbents for removal of bacterial contaminants from water sources.

    Science.gov (United States)

    Hassouna, M E M; ElBably, M A; Mohammed, Asmaa N; Nasser, M A G

    2017-02-01

    This work evaluated the antimicrobial efficacy of kaolin clay and its loaded forms with carbon nanotubes (CNTs) and silver nanoparticles (AgNPs) against bacterial isolates from different water supplies (tap, underground and surface water) in addition to wastewater. A total of 160 water samples were collected from different water sources in the investigated districts. Samples were cultured for isolation and serological identification of pathogenic bacteria. AgNPs were synthesized by a typical one-step synthesis protocol, where CNTs were carried out in a reactor employing the double bias-assisted hot filament chemical vapor deposition method. Both were characterized using transmission electron microscopy, infrared and X-ray fluorescence (XRF) spectroscopy. The antimicrobial efficacy of each of natural kaolin clay, AgNPs- and CNTs-loaded clays were evaluated by their application in four concentrations (0.01, 0.03, 0.05 and 0.1 ppm) at different contact times (5 min, 15 min, 30 min and 2 h). AgNPs-loaded clays at concentrations of 0.05 and 0.1 mg/l for 2 h contact time exhibited a higher bactericidal efficacy on Escherichia coli and Salmonella spp. (70, 70, 80 and 90%, respectively) compared to CNTs-loaded clay. Concluding, the application of AgNPs-loaded clay for removal of water bacterial contaminants at a concentration of 0.1 ppm for 2 h contact times resulted in highly effective removals.

  2. The Use of Water Plants for Storm Water Runoff Treatment

    Directory of Open Access Journals (Sweden)

    Lina Varneckaitė

    2011-04-01

    Full Text Available The popularity of using water plants for storm water runoff treatment has been largely due to the fact that pond and wetland based systems offer the advantages of providing a relatively passive, natural, low-maintenance and operationally simple treatment solution while enhancing habitat and aesthetic values at the same time. While ponds are generally effective at removing coarse suspended sediments, they are less effective at removing finer particulates and dissolved contaminants. To provide enhanced treatment, a wetland can be placed downstream of a pond.Article in Lithuanian

  3. Water Treatment Technology - Taste, Odor & Color.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on taste, odor, and color provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: taste and odor determination, control of…

  4. Water Treatment Technology - Cross-Connections.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on cross connections provides instructional materials for two competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on cross connections terminology and control devices. For each…

  5. availability analysis of chemicals for water treatment

    African Journals Online (AJOL)

    NIJOTECH

    Nigerian Journal of Technology, Vol. 25, No. 1, March 2005. Anyata and Obiasor. 75. The calls for increased demand of water treatment chemicals. This model to be formulated is based on the need to reduce shortages of chemicals in the water supply industries while minimizing direct cost of supplying chemicals.

  6. Interfacial Shear Rheology of β-Lactoglobulin - Bovine Submaxillary Mucin Layers Adsorbed at Air/Water Interface

    DEFF Research Database (Denmark)

    Celebioglu, Hilal Yilmaz; Kmiecik-Palczewska, Joanna; Lee, Seunghwan

    2017-01-01

    that hydrophobic patches of BSM can be imbedded into the BLG monolayer as driven by a strong hydrophobic interaction with air and disrupt the cohesive assembly of BLG, whereas the hydrophilic (negatively charged) parts of the BSM chain are protruding from the interface towards the bulk water.......The interfacial rheological properties of solutions of β-lactoglobulin (BLG), as a model food compound, mixed with bovine submaxillary mucin (BSM), a major salivary protein, have been investigated. Time, frequency, stress sweep and flow measurements have been performed at different pHs (7.4, 5.......0 and 3.0), to investigate the air/water interfacial properties. All protein layers (BLG, BSM, and BLG-BSM mixtures) formed an elastic network at the air/water interface with low frequency dependence of the interfacial modulus. The results indicated that BLG moves faster as smaller molecule than mucin...

  7. Alkaline treatment of timber sawdust: A straightforward route toward effective low-cost adsorbent for the enhanced removal of basic dyes from aqueous solutions

    Directory of Open Access Journals (Sweden)

    Yamina Djilali

    2016-09-01

    Full Text Available The present study assesses the ability of two low-cost adsorbents – timber sawdust (TS–OH and its alkaline treated analog (TS–ONa – to remove two basic dyes, namely, Methylene Blue and Methyl Green, from aqueous solutions. The presence of new functional groups on the surface of TS–ONa resulted in a dramatic increase of surface polarity and the density of sorption sites, thereby improving the sorption efficiency of the cationic dyes. The results obtained from the sorption characteristics have revealed that the sorption process for TS–ONa was uniform and rapid. The adsorption of cationic dyes reached equilibrium within the first 10 min of contact time and the treated material acts efficiently in a wide pH range of dye solutions. The extent of adsorption was measured through equilibrium sorption isotherms and analyzed using the Langmuir model. The monolayer saturation capacities for Methylene Blue are 694.44 and 1928.31 mg g−1 and for Methyl Green are 892.86 and 1821.33 mg g−1 for TS–OH and TS–ONa, respectively. Therefore, the chemically treated sawdust proved two- to threefold higher adsorption capacities of these dyes than those of the untreated analog. The exothermic nature of adsorption is demonstrated by a decrease of adsorption capacity with increasing temperature, and the negative value of free energy change indicated the spontaneity of adsorption. Desorption experiments with 1 M aqueous NaCl put into evidence that cationic dyes were completely desorbed from the matrices and the reusability of the TS–ONa matrix after three repeated cycles led to just a slight attenuation in its performance. These results show that alkaline treatment of a low value by-product of the timber industry leads to a powerful and efficient low-cost adsorbent, which may be used for the treatment of colored wastewaters.

  8. Comparative analysis of the efficiencies of two low cost adsorbents ...

    African Journals Online (AJOL)

    ISHIOMA

    were also used to investigate the mechanism of adsorption. MATERIALS AND METHODS. Adsorbents. The adsorbents were prepared as described by Hanafiah et al. (2006). Each of the adsorbents (coconut husk and teak tree bark) were cut into small pieces and blended. They were washed with distilled water to remove ...

  9. Waste water treatment in Bukkerup (VB)

    DEFF Research Database (Denmark)

    Thomsen, Rikke; Overgaard, Morten; Jørgensen, Michael Søgaard

    1999-01-01

    In connection to the new waste water plan of Tølløse municipal the technical and environmental board has suggested that Bukkerup get a sewer system which brings the waste water to the treatment plant for Tysinge. All though the residents would like to list alternative suggestions which improve...... the local water environment but is still competitive.In this report the alternatives are listed, e.i. root system plants, sand filters and mini treatment plants.The conclusion is that root system plants and a combination of root system plants and sand filters are better that the sewer system....

  10. Study of the elimination of fluorine from drinking water using adsorbent materials; Estudio de la eliminacion de fluor del agua potable utilizando materiales adsorbentes

    Energy Technology Data Exchange (ETDEWEB)

    Flores de la Torre, J.A.; Badillo A, V.E.; Badillo A, V. [UAZ, 98600 Guadalupe, Zacatecas (Mexico); Lopez D, F.A. [Unidad PET/Ciclotron, Facultad de Medicina, UNAM, 04510 Mexico D.F. (Mexico)]. E-mail: ebadillo@cantera.reduaz.mx

    2004-07-01

    With the purpose of diminishing the levels of fluorine in the water in certain areas geographical of the country, the interaction of the fluorine is studied, with a Mexican natural clay, called kaolinite and a synthetic apatite called hydroxyapatite. Due to the discharges concentrations of this element in waters of human consumption cause fluorosis dental and osseous, it is important to propose adsorbent materials able to diminish those elevated concentrations of fluorine. In this investigation work the retention of the fluorine is studied in mineral phases using the tracer radioactive {sup 8} F. This retention is expressed in terms of the fixed percent of {sup 18} F, in a natural kaolinite in solution of NaCl 0.01 M, and in a synthetic hydroxyapatite setting in contact with a solution of NaF 0.01 M and a solution of NaH{sub 2}PO{sub 4} 0.01 M, all in function of the value of the p H of the solution. The results demonstrate that the influence of the p H is remarkable in the retention of the fluoride in both minerals, demonstrating that the hydroxyapatite (calcium phosphate) it retains in a lot of bigger proportion to the fluorine that the kaolinite (aluminosilicate), all this to values of acid p H, diminishing as the value of the p H increases. (Author)

  11. Rational design of nanomaterials for water treatment

    KAUST Repository

    Li, Renyuan

    2015-08-26

    The ever-increasing human demand for safe and clean water is gradually pushing conventional water treatment technologies to their limits and it is now a popular perception that the solutions to the existing and future water challenges will highly hinge upon the further development of nanomaterial sciences. The concept of rational design emphasizes ‘design-for-purpose’ and it necessitates a scientifically clear problem definition to initiate the nanomaterial design. The field of rational design of nanomaterials for water treatment has experienced a significant growth in the past decade and is poised to make its contribution in creating advanced next-generation water treatment technologies in the years to come. Within the water treatment context, this review offers a comprehensive and in-depth overview of the latest progress of the rational design, synthesis and applications of nanomaterials in adsorption, chemical oxidation and reduction reactions, membrane-based separation, oil/water separation, and synergistic multifunctional all-in-one nanomaterials/nanodevices. Special attention is paid on chemical concepts of the nanomaterial designs throughout the review.

  12. Rational design of nanomaterials for water treatment

    Science.gov (United States)

    Li, Renyuan; Zhang, Lianbin; Wang, Peng

    2015-10-01

    The ever-increasing human demand for safe and clean water is gradually pushing conventional water treatment technologies to their limits. It is now a popular perception that the solutions to the existing and future water challenges will hinge upon further developments in nanomaterial sciences. The concept of rational design emphasizes on `design-for-purpose' and it necessitates a scientifically clear problem definition to initiate the nanomaterial design. The field of rational design of nanomaterials for water treatment has experienced a significant growth in the past decade and is poised to make its contribution in creating advanced next-generation water treatment technologies in the years to come. Within the water treatment context, this review offers a comprehensive and in-depth overview of the latest progress in rational design, synthesis and applications of nanomaterials in adsorption, chemical oxidation and reduction reactions, membrane-based separation, oil-water separation, and synergistic multifunctional all-in-one nanomaterials/nanodevices. Special attention is paid to the chemical concepts related to nanomaterial design throughout the review.

  13. A new approach for water treatment

    CERN Document Server

    Principe, R

    1999-01-01

    A quantity of up to 4000 m3/h of water is used at CERN for cooling purposes: experiments, magnets and radio frequency cavities are refrigerated by closed circuits filled with deionized water; other utilities, such as air-conditioning, use chilled/hot water, also in closed circuits. All these methods all employ a cold source, the primary supply of water, coming from the cooling towers. About 500 kCHF are spent every year on water treatment in order to keep the water within these networks in operational conditions. In the line of further rationalization of resources, the next generation of contracts with the water treatment industry will aim for improved performance and better monitoring of quality related parameters in this context. The author will provide a concise report based upon an examination of the state of the installations and of the philosophy followed up until now for water treatment. Furthermore, he/she will propose a new approach from both a technical and contractual point of view, in preparation ...

  14. An evaluation of Hanford water treatment practices

    Energy Technology Data Exchange (ETDEWEB)

    Touhill, C.J.

    1965-09-01

    An evaluation of Hanford reactor process water treatment practices was made in an effort to ascertain the reasons for variations in the effluent activity between reactors. Recommendations are made for improvements in unit processes as well as for the over-all treatment process based on field inspection of the water treatment plants. In addition, a research program is proposed to supplement the recommendations. The proposed research is designed to uncover methods of more efficient filtration as well as other procedures which might eventually lead to significant effluent activity reductions. The recommendations and research results will be applied toward process optimization.

  15. Behavior of gadolinium-based diagnostics in water treatment

    Energy Technology Data Exchange (ETDEWEB)

    Cyris, Maike

    2013-04-25

    determined, however, it is strongly assumed that the anthropogenic gadolinium fraction is present as chelate. Adsorption characteristics were evaluated by bottle point isotherm experiments on different activated carbon types and activated polymer based sorbents. The Freundlich coefficients vary between 0.013 and 2.83 (μmol kg{sup -1})(L μmol{sup -1}){sup 1/n} for Gd-BT-DO3A, on Chemviron RD 90 {sup registered} and on the best synthetic adsorbent, respectively. Lab scale experiments with small adsorber columns in a drinking water matrix gave insight in the behavior during fixed-bed adsorption processes. The breakthrough was described successfully by the Linear Driving Force model. Modeling has shown that a description of experimental results is only possible by including dissolved organic carbon isotherm results from drinking water in the model, to describe an additional competitive adsorption effect within the fixed-bed adsorber, different from direct competition. First investigations in a wastewater treatment plant proved a poor adsorption of gadolinium similar to iodinated X-ray contrast media such as iopamidole. Therefore, gadolinium will hardly be removed from wastewater by implementation of a further adsorptive treatment step. However, gadolinium may be utilized as indicator substance for breakthrough. Rate constants of the chelates with ozone and hydroxyl radicals have been determined under pseudo-first-order conditions. Rate constants for the ozone reaction were determined to be < 50 M{sup -1}s{sup -1} for all tested chelates. Hence, the chelates may be considered ozone refractory. For determination of hydroxyl radical rate constants different methods were applied. Radicals were generated either by pulse radiolysis, in this case rate constant were determined directly and by competition with thiocyanate, or by the peroxone process, where only competition kinetics were applied (para-chlorobenzoic acid and tert-butanol as competitors). From pulse radiolysis

  16. Sense or no-sense of the sum parameter for water soluble "adsorbable organic halogens" (AOX) and "absorbed organic halogens" (AOX-S18) for the assessment of organohalogens in sludges and sediments.

    Science.gov (United States)

    Müller, German

    2003-07-01

    "AOX" is the abbreviation of the sum parameter for water soluble "adsorbable organic halogens" in which 'A' stands for adsorbable, 'O' for organic and 'X' for the halogens chlorine, bromine and iodine. After the introduction of the AOX in 1976, this parameter has been correctly used for "real" AOX constituents (DDT and its metabolites, PCBs, etc.) but also misused for non-adsorbable adsorbed OX-compounds, mostly high molecular organohalogens in plants and even to inorganic compounds being neither organic nor adsorbable. The question of natural "Adsorbable Organic Halogens" (AOX) formed by living organisms and/or during natural abiogenic processes has been definitively solved by the known existence of already more than 3650 organohalogen compounds, amongst them the highly reactive, cancerogenic vinyl chloride (VC). The extension of the AOX to AOX-S18 for Sludges and Sediments, in which A stands for adsorbed (not for adsorbable) is questionable. It includes the most important water insoluble technical organochlorine product: polyvinyl chloride, PVC. In addition to organic halogens it also includes inorganic, mineralogenic halides, incorporated mainly in the crystal lattice of fine grained phyllosilicates, the typical clay minerals (kaolinite, montmorillonite, illite and chlorite) which are main constituents of sediments and sedimentary rocks representing the major part of the sedimentary cover of the earth. Other phyllosilicates, biotite and muscovite, major constituents of granites and many metamorphic rocks (gneiss and mica schist) will also contribute to the AOX-S18 especially in soils as result of weathering processes. Since chlorine is incorporated into the mineral structure and, as a consequence, not soluble by the nitric acid analytical step (pH 0.5) of the S18 determination, it will account to the AOX-S18 in the final charcoal combustion step at temperatures >950 degrees C. After heavy rainfalls sewage sludge composition is strongly influenced by

  17. DIAGNOSIS AND TREATMENT OF WATERING EYE

    Directory of Open Access Journals (Sweden)

    Brigita Drnovšek Olup

    2016-07-01

    Full Text Available Background: Watering eye is in the population a very common eye phenomenon. Watering eye is presented with excessive amount of tears on the surface of the eye that are spilled over the edge of the eyelid on the skin of the eyelids and face. Basically, watering eye is divided into excessive tearing or lacrimation and on the lack of drainage of tears or epiphora. Only correct identification of both phenomena can lead to successful treatment of several patients.Methods: The article presents the anatomy and physiology of lacrimal system causes for lacrimation and epiphora, diagnostic tests and types of treatment. Laser treatment method for epiphora which is performed at the Eye Hospital in Ljubljana is presented.Results: The most common cause for epiphora is nasolacrimal duct occlusion, which is treated by dacryocystorhinostomy. With the minimally invasive version of this treatment method, transcanalicular laser dacryocystorhinostomy, we are able to treat epiphora in 85% of cases.Conclusions: Proper diagnosis and treatment of watering eye is important because of the impact of tearing on a number of eye processes. Incorrectly identified causes and treatment deteriorate patients' quality of life with decreased visual acuity and disrupted social contacts. In the article we show the contribution of the Eye Hospital in Ljubljana to the successful treatment of epiphora with transcanalicular diode laser-assisted dacryocystorhinostomy.

  18. Nanotechnology-based water treatment strategies.

    Science.gov (United States)

    Kumar, Sandeep; Ahlawat, Wandit; Bhanjana, Gaurav; Heydarifard, Solmaz; Nazhad, Mousa M; Dilbaghi, Neeraj

    2014-02-01

    The most important component for living beings on the earth is access to clean and safe drinking water. Globally, water scarcity is pervasive even in water-rich areas as immense pressure has been created by the burgeoning human population, industrialization, civilization, environmental changes and agricultural activities. The problem of access to safe water is inevitable and requires tremendous research to devise new, cheaper technologies for purification of water, while taking into account energy requirements and environmental impact. This review highlights nanotechnology-based water treatment technologies being developed and used to improve desalination of sea and brackish water, safe reuse of wastewater, disinfection and decontamination of water, i.e., biosorption and nanoadsorption for contaminant removal, nanophotocatalysis for chemical degradation of contaminants, nanosensors for contaminant detection, different membrane technologies including reverse osmosis, nanofiltration, ultrafiltration, electro-dialysis etc. This review also deals with the fate and transport of engineered nanomaterials in water and wastewater treatment systems along with the risks associated with nanomaterials.

  19. Innovations in nanotechnology for water treatment

    Directory of Open Access Journals (Sweden)

    Gehrke I

    2015-01-01

    Full Text Available Ilka Gehrke, Andreas Geiser, Annette Somborn-SchulzFraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT, Oberhausen, GermanyAbstract: Important challenges in the global water situation, mainly resulting from worldwide population growth and climate change, require novel innovative water technologies in order to ensure a supply of drinking water and reduce global water pollution. Against this background, the adaptation of highly advanced nanotechnology to traditional process engineering offers new opportunities in technological developments for advanced water and wastewater technology processes. Here, an overview of recent advances in nanotechnologies for water and wastewater treatment processes is provided, including nanobased materials, such as nanoadsorbents, nanometals, nanomembranes, and photocatalysts. The beneficial properties of these materials as well as technical barriers when compared with conventional processes are reported. The state of commercialization is presented and an outlook on further research opportunities is given for each type of nanobased material and process. In addition to the promising technological enhancements, the limitations of nanotechnology for water applications, such as laws and regulations as well as potential health risks, are summarized. The legal framework according to nanoengineered materials and processes that are used for water and wastewater treatment is considered for European countries and for the USA.Keywords: nanotechnology, water technology, nanoadsorbents, nanometals, nanomembranes, photocatalysis

  20. Long Term 1 Enhanced Surface Water Treatment Rule Documents

    Science.gov (United States)

    The Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) builds on the requirements of the Surface Water Treatment Rule and specifies treatment requirements to address Cryptosporidium m and other microbial contaminants in public water systems.

  1. Evaluating Nanoparticle Breakthrough during Drinking Water Treatment

    Science.gov (United States)

    Chalew, Talia E. Abbott; Ajmani, Gaurav S.; Huang, Haiou

    2013-01-01

    Background: Use of engineered nanoparticles (NPs) in consumer products is resulting in NPs in drinking water sources. Subsequent NP breakthrough into treated drinking water is a potential exposure route and human health threat. Objectives: In this study we investigated the breakthrough of common NPs—silver (Ag), titanium dioxide (TiO2), and zinc oxide (ZnO)—into finished drinking water following conventional and advanced treatment. Methods: NPs were spiked into five experimental waters: groundwater, surface water, synthetic freshwater, synthetic freshwater containing natural organic matter, and tertiary wastewater effluent. Bench-scale coagulation/flocculation/sedimentation simulated conventional treatment, and microfiltration (MF) and ultrafiltration (UF) simulated advanced treatment. We monitored breakthrough of NPs into treated water by turbidity removal and inductively coupled plasma–mass spectrometry (ICP-MS). Results: Conventional treatment resulted in 2–20%, 3–8%, and 48–99% of Ag, TiO2, and ZnO NPs, respectively, or their dissolved ions remaining in finished water. Breakthrough following MF was 1–45% for Ag, 0–44% for TiO2, and 36–83% for ZnO. With UF, NP breakthrough was 0–2%, 0–4%, and 2–96% for Ag, TiO2, and ZnO, respectively. Variability was dependent on NP stability, with less breakthrough of aggregated NPs compared with stable NPs and dissolved NP ions. Conclusions: Although a majority of aggregated or stable NPs were removed by simulated conventional and advanced treatment, NP metals were detectable in finished water. As environmental NP concentrations increase, we need to consider NPs as emerging drinking water contaminants and determine appropriate drinking water treatment processes to fully remove NPs in order to reduce their potential harmful health outcomes. Citation: Abbott Chalew TE, Ajmani GS, Huang H, Schwab KJ. 2013. Evaluating nanoparticle breakthrough during drinking water treatment. Environ Health Perspect 121

  2. Arsenic Removal from Water Using Various Adsorbents: Magnetic Ion Exchange Resins, Hydrous Ion Oxide Particles, Granular Ferric Hydroxide, Activated Alumina, Sulfur Modified Iron, and Iron Oxide-Coated Microsand

    KAUST Repository

    Sinha, Shahnawaz

    2011-09-30

    The equilibrium and kinetic adsorption of arsenic on six different adsorbents were investigated with one synthetic and four natural types (two surface and two ground) of water. The adsorbents tested included magnetic ion exchange resins (MIEX), hydrous ion oxide particles (HIOPs), granular ferric hydroxide (GFH), activated alumina (AA), sulfur modified iron (SMI), and iron oxide-coated mic - rosand (IOC-M), which have different physicochemical properties (shape, charge, surface area, size, and metal content). The results showed that adsorption equilibriums were achieved within a contact period of 20 min. The optimal doses of adsorbents determined for a given equilibrium concentration of C eq = 10 μg/L were 500 mg/L for AA and GFH, 520–1,300 mg/L for MIEX, 1,200 mg/L for HIOPs, 2,500 mg/L for SMI, and 7,500 mg/L for IOC-M at a contact time of 60 min. At these optimal doses, the rate constants of the adsorbents were 3.9, 2.6, 2.5, 1.9, 1.8, and 1.6 1/hr for HIOPs, AA, GFH, MIEX, SMI, and IOC-M, respectively. The presence of silicate significantly reduced the arsenic removal efficiency of HIOPs, AA, and GFH, presumably due to the decrease in chemical binding affinity of arsenic in the presence of silicate. Additional experiments with natural types of water showed that, with the exception of IOC-M, the adsorbents had lower adsorption capacities in ground water than with surface and deionized water, in which the adsorption capacities decreased by approximately 60–95 % .

  3. Fate of Carbamazepine during Water Treatment

    DEFF Research Database (Denmark)

    Kosjek, T.; Andersen, Henrik Rasmus; Kompare, Boris

    2009-01-01

    Seven transformation products of carbamazepine generated by at least one of three common water treatment technologies (W-radiation, oxidation with chlorine dioxide (ClO2), and biological treatment with activated Sludge) were identified by complementary use of ion trap, single quadrupole, and quad......Seven transformation products of carbamazepine generated by at least one of three common water treatment technologies (W-radiation, oxidation with chlorine dioxide (ClO2), and biological treatment with activated Sludge) were identified by complementary use of ion trap, single quadrupole...... compared the treatment technologies according to the removal of carbamazepine and the production and decay of its transformation products. The most successful method for the removal of carbamazepine was UV treatment, while acridine and acridone were more susceptible to biological treatment. Therefore......, based on the enhanced biodegradability of carbamazepine residues achieved by UV irradiation, we propose a coupled treatment technology involving an initial UV treatment step followed by biological treatment, which may satisfactorily remove the parent compound and its transformation products....

  4. Cassava root husks powder as green adsorbent for the removal of Cu(II) from natural river water

    Energy Technology Data Exchange (ETDEWEB)

    Jorgetto, A.O.; Silva, R.I.V.; Saeki, M.J.; Barbosa, R.C. [IB-UNESP, Dept. Química e Bioquímica, C.P. 510, 18618-000 Botucatu, SP (Brazil); Martines, M.A.U. [UFMS – Dept. Química, 79074-460 Campo Grande, MS (Brazil); Jorge, S.M.A.; Silva, A.C.P. [IB-UNESP, Dept. Química e Bioquímica, C.P. 510, 18618-000 Botucatu, SP (Brazil); Schneider, J.F. [USP – Instituto de Física de São Carlos, 13566-590 São Carlos, SP (Brazil); Castro, G.R., E-mail: castrogr@ibb.unesp.br [IB-UNESP, Dept. Química e Bioquímica, C.P. 510, 18618-000 Botucatu, SP (Brazil)

    2014-01-01

    Through a series of simple processes, cassava root husks were turned into a fine powder of controlled particle size (63–75 μm). FTIR spectrum demonstrated the existence of alcohol, amine and carboxylic groups; and elemental analysis confirmed the presence of elements of interest such as sulphur, nitrogen and oxygen. Cross-polarized {"1H}-{sup 13}C NMR technique indicated the existence of methionine and thiamine through the signals observed at 55 ppm and 54 ppm, respectively, and the point of zero charge (pH{sub pzc}) was achieved at pH 5.2. The material was applied in solid-phase extraction of Cu(II) via batch experiments. Optimum adsorption pH was found to be in range of 3–6 and in the kinetic experiment the equilibrium was attained in 1 min. The highest adsorption capacity was 0.14 mmol g{sup −1}. The adsorption data were fit to the modified Langmuir equation, and the maximum amount of metal species extracted from the solution, N{sub s}, was determined to be ∼0.14 mmol g{sup −1}, which is an indicative that the main adsorption mechanism is through chemisorption. Under optimized conditions, the material was utilized in preconcentration experiments, which culminated in an enrichment factor of 41.3-fold. With the aid of the enrichment factor, experiments were carried out to determine the Cu(II) content in tap water and natural water. Preconcentration method was also applied to a certified reference material (1643e) and the concentration found was 23.03 ± 0.79 μg L{sup −1}, whereas the specified Cu(II) concentration was 22.7 ± 0.31 μg L{sup −1}.

  5. Innovations in nanotechnology for water treatment.

    Science.gov (United States)

    Gehrke, Ilka; Geiser, Andreas; Somborn-Schulz, Annette

    2015-01-01

    Important challenges in the global water situation, mainly resulting from worldwide population growth and climate change, require novel innovative water technologies in order to ensure a supply of drinking water and reduce global water pollution. Against this background, the adaptation of highly advanced nanotechnology to traditional process engineering offers new opportunities in technological developments for advanced water and wastewater technology processes. Here, an overview of recent advances in nanotechnologies for water and wastewater treatment processes is provided, including nanobased materials, such as nanoadsorbents, nanometals, nanomembranes, and photocatalysts. The beneficial properties of these materials as well as technical barriers when compared with conventional processes are reported. The state of commercialization is presented and an outlook on further research opportunities is given for each type of nanobased material and process. In addition to the promising technological enhancements, the limitations of nanotechnology for water applications, such as laws and regulations as well as potential health risks, are summarized. The legal framework according to nanoengineered materials and processes that are used for water and wastewater treatment is considered for European countries and for the USA.

  6. Biochar-based water treatment systems as a potential low-cost and sustainable technology for clean water provision.

    Science.gov (United States)

    Gwenzi, Willis; Chaukura, Nhamo; Noubactep, Chicgoua; Mukome, Fungai N D

    2017-07-15

    Approximately 600 million people lack access to safe drinking water, hence achieving Sustainable Development Goal 6 (Ensure availability and sustainable management of water and sanitation for all by 2030) calls for rapid translation of recent research into practical and frugal solutions within the remaining 13 years. Biochars, with excellent capacity to remove several contaminants from aqueous solutions, constitute an untapped technology for drinking water treatment. Biochar water treatment has several potential merits compared to existing low-cost methods (i.e., sand filtration, boiling, solar disinfection, chlorination): (1) biochar is a low-cost and renewable adsorbent made using readily available biomaterials and skills, making it appropriate for low-income communities; (2) existing methods predominantly remove pathogens, but biochars remove chemical, biological and physical contaminants; (3) biochars maintain organoleptic properties of water, while existing methods generate carcinogenic by-products (e.g., chlorination) and/or increase concentrations of chemical contaminants (e.g., boiling). Biochars have co-benefits including provision of clean energy for household heating and cooking, and soil application of spent biochar improves soil quality and crop yields. Integrating biochar into the water and sanitation system transforms linear material flows into looped material cycles, consistent with terra preta sanitation. Lack of design information on biochar water treatment, and environmental and public health risks constrain the biochar technology. Seven hypotheses for future research are highlighted under three themes: (1) design and optimization of biochar water treatment; (2) ecotoxicology and human health risks associated with contaminant transfer along the biochar-soil-food-human pathway, and (3) life cycle analyses of carbon and energy footprints of biochar water treatment systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Individual and combined effects of water quality and empty bed contact time on As(V) removal by a fixed-bed iron oxide adsorber: implication for silicate precoating.

    Science.gov (United States)

    Kanematsu, Masakazu; Young, Thomas M; Fukushi, Keisuke; Green, Peter G; Darby, Jeannie L

    2012-10-15

    The individual and combined effects of changes in water quality (i.e. pH, initial concentrations of arsenate (As(V)) and competing ions) and empty bed contact time (EBCT) on As(V) removal performance of a fixed-bed adsorber (FBA) packed with a nanostructured goethite-based granular porous adsorbent were systematically studied under environmentally relevant conditions. Rapid small scale column tests (RSSCTs) were extensively conducted at different EBCTs with synthetic waters in which pH and the concentrations of competing ions (phosphate, silicate, and vanadate) were controlled. In the absence of the competing ions, the effects of initial As(V) concentration, pH, and EBCT on As(V) breakthrough curves were successfully predicted by the homogeneous surface diffusion model (HSDM) with adsorption isotherms predicted by the extended triple layer model (ETLM). The interference effects of silicate and phosphate on As(V) removal were strongly influenced by pH, their concentrations, and EBCT. In the presence of silicate (≤21 mg/L as Si), a longer EBCT surprisingly resulted in worse As(V) removal performance. We suggest this is because silicate, which normally exists at much higher concentration and moves more quickly through the bed than As(V), occupies or blocks adsorption sites on the media and interferes with later As(V) adsorption. Here, an alternative operating scheme of a FBA for As(V) removal is proposed to mitigate the silicate preloading. Silicate showed a strong competing effect to As(V) under the tested conditions. However, as the phosphate concentration increased, its interference effect dominated that of silicate. High phosphate concentration (>100 μg/L as P), as experienced in some regions, resulted in immediate As(V) breakthrough. In contrast to the observation in the presence of silicate, longer EBCT resulted in improved As(V) removal performance in the presence of phosphate. Vanadate was found to compete with As(V) as strongly as phosphate. This study

  8. Selective cesium removal from radioactive liquid waste by crown ether immobilized new class conjugate adsorbent.

    Science.gov (United States)

    Awual, Md Rabiul; Yaita, Tsuyoshi; Taguchi, Tomitsugu; Shiwaku, Hideaki; Suzuki, Shinichi; Okamoto, Yoshihiro

    2014-08-15

    Conjugate materials can provide chemical functionality, enabling an assembly of the ligand complexation ability to metal ions that are important for applications, such as separation and removal devices. In this study, we developed ligand immobilized conjugate adsorbent for selective cesium (Cs) removal from wastewater. The adsorbent was synthesized by direct immobilization of dibenzo-24-crown-8 ether onto inorganic mesoporous silica. The effective parameters such as solution pH, contact time, initial Cs concentration and ionic strength of Na and K ion concentrations were evaluated and optimized systematically. This adsorbent was exhibited the high surface area-to-volume ratios and uniformly shaped pores in case cavities, and its active sites kept open functionality to taking up Cs. The obtained results revealed that adsorbent had higher selectivity toward Cs even in the presence of a high concentration of Na and K and this is probably due to the Cs-π interaction of the benzene ring. The proposed adsorbent was successfully applied for radioactive Cs removal to be used as the potential candidate in Fukushima nuclear wastewater treatment. The adsorbed Cs was eluted with suitable eluent and simultaneously regenerated into the initial form for the next removal operation after rinsing with water. The adsorbent retained functionality despite several cycles during sorption-elution-regeneration operations. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Obtaining and Application of New Cellulose- and Graphene Oxide-Based Adsorbents for Treatment of Industrial Waste Containing Heavy Metals

    OpenAIRE

    Beata Fryczkowska; Mirosław Wyszomirski; Monika Puzoń

    2017-01-01

    The paper presents the results of studies on the preparation and properties of composite granules produced by phase inversion from cellulose (CEL) solutions in 1-ethyl-3-methylimidazole acetate (EMIMAc), containing nano-addition in the form of graphene oxide (GO) in N,N-dimethylformamide (DMF). Water absorption and sorption of such compounds as FeCl3, methylene blue (MB) and bovine serum albumin (BSA) were studied. In addition, attempts were made to investigate the sorption properties of the ...

  10. Rice water in treatment of infantile gastroenteritis.

    Science.gov (United States)

    Wong, H B

    1981-07-11

    In Singapore the World Health Organization's (WHO's) oral electrolyte solution for the treatment of infantile gastroenteritis has been used for 6 years and rice water has been used for 8 years. The rice water is the water used in preparing boiled rice or congee and is a slightly starchy solution. As the impression was that rice water was as effective as or even better than the oral electrolyte solution, a trial was conducted of the 2 solutions in babies with gastroenteritis admitted to the Department of Pediatrics of the National University of Singapore. Alternate cases were assigned consecutively to the oral electrolyte solution or to rice water. There were 63 patients on oral electrolyte and 67 on rice water. Milk was totally withdrawn for 24 hours after admission and the babies were put on 1 or the other oral solution. Intravenous 3.75% glucose and 0.23% saline was given at the same time to babies considered to be more dehydrated. On day 2, quarter strength powdered milk was given, followed by half strength on day 3, three-quarters strength on day 4, and full strength on day 5. Electrolyte and urea values were compared, both for "drip" versus "no drip" within oral treatment groups and between electrolyte solution and rice water groups (20 comparisons altogether). There were only 3 significant differences, and these might be explained by the intravenous drip and by the better water absorption from rice water than from the oral electrolyte solution. The most obvious difference in the 2 groups was in the effect on diarrhea (stools/day). Rice water cut down the number of stools more effectively than did oral electrolyte solution. No patient died, and there were no pathological sequelae in any of the 130 patients. Rice water can be tried as a more practical alternative to oral electrolyte solutions since there are problems with providing oral elecrolyte solutions to all babies with diarrhea in the developing countries and ensuring sterility.

  11. One pot synthesis of magnetic graphene/carbon nanotube composites as magnetic dispersive solid-phase extraction adsorbent for rapid determination of oxytetracycline in sewage water.

    Science.gov (United States)

    Sun, Yunyun; Tian, Jing; Wang, Lu; Yan, Hongyuan; Qiao, Fengxia; Qiao, Xiaoqiang

    2015-11-27

    A simple and time-saving one pot synthesis of magnetic graphene/carbon nanotube composites (M-G/CNTs) was developed that could avoid the tedious drying process of graphite oxide, and G/CNTs were modified by Fe3O4 nanoparticles in the reduction procedure. It contributed to a shorten duration of the synthesis process of M-G/CNTs. The obtained M-G/CNTs were characterized and the results indicated that CNTs and Fe3O4 nanoparticles were served as spacer distributing to the layers of graphene, which was beneficial for enlarging surface area and improving extraction efficiency. Moreover, M-G/CNTs showed good magnetic property and outstanding thermal stability. Then M-G/CNTs were applied as adsorbent of magnetic dispersive solid-phase extraction for rapid extraction and determination of oxytetracycline in sewage water. Under the optimum conditions, good linearity was obtained in the range of 20-800ngmL(-1) and the recoveries were ranged from 95.5% to 112.5% with relative standard deviations less than 5.8%. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Photophysical Studies of a New Water Soluble Indocarbocyanine Dye Adsorbed onto Microcrystalline Cellulose and b-Cyclodextrin

    Directory of Open Access Journals (Sweden)

    Luis F. Vieira Ferreira

    2013-05-01

    Full Text Available A water-soluble indocarbocyanine dye was synthesized and its photophysics were studied for the first time on two solid hosts, microcrystalline cellulose and b-cyclodextrin, as well as in homogeneous media. The inclusion of the indocarbocyanine moiety onto microcrystalline cellulose increased the dye aggregation with both H and J aggregates being formed. Adsorption on b-cyclodextrin enhanced aggregation in a similar way. The fluorescence quantum yields were determined for the powdered samples of the cyanine dye on the two hosts and a significant increase was observed relative to homogeneous solution. A remarkable concentration dependence was also detected in both cases. A lifetime distribution analysis has shown that the indocarbocyanine dye mainly occupies the amorphous part of cellulose and is not entrapped in the crystalline part of this host. In the b-CD case, the adsorption occurs outside the host cavity. In both hosts a strong concentration quenching effect is observed and only monomers emit. Both adsorptions may be explained by stereochemical constraints imposed by the two long sulphoethyl tails linked to nitrogen atoms of the indocarbocyanine dye.

  13. Water Purification by Using Microplasma Treatment

    Science.gov (United States)

    Shimizu, K.; Masamura, N.; Blajan, M.

    2013-06-01

    Dielectric barrier discharge microplasma generated at the surface of water is proposed as a solution for water treatment. It is an economical and an ecological technology for water treatment due to its generation at atmospheric pressure and low discharge voltage. Microplasma electrodes were placed at small distance above the water thus active species and radicals were flown by the gas towards the water surface and furthermore reacted with the target to be decomposed. Indigo carmine was chosen as the target to be decomposed by the effect of active species and radicals generated between the electrodes. Air, oxygen, nitrogen and argon were used as discharge gases. Measurement of absorbance showed the decomposition of indigo carmine by microplasma treatment. Active species and radicals of oxygen origin so called ROS (reactive oxidative species) were considered to be the main factor in indigo carmine decomposition. The decomposition rate increased with the increase of the treatment time as shown by the spectrophotometer analysis. Discharge voltage also influenced the decomposition process.

  14. Radiolysis of adsorbed water molecules on Al/sub 2/O/sub 3/, La/sub 2/O/sub 3/, Er/sub 2/O/sub 3/ and BeO. [Gamma Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Garibov, A.A.; Melikzade, M.M.; Bakirov, M.Ya.; Ramazanova, M.K.

    The oxides were studied by first conditioning them at 500/sup 0/C for 12 h, and then processing them in a vacuum for 5 h at 350/sup 0/C. Double-distilled water was used for the adsorption tests. Ampules containing the oxides were irradiated with gamma radiation from /sup 60/Co. Analysis of radiolysis products showed H/sub 2/ and O/sub 2/ content in proportions above stoichiometric norms, indicating oxygen entrapment in the oxide structures. Hydrogen yield corresponded to the quantity of water molecules subjected to radiolysis. The oxides had a catalytic effect on the radiation chemical decomposition of the water, and were able to transmit absorbed energy from ionizing radiation to molecules adsorbed on their surfaces. BeO had relatively high catalytic activity, apparently due to a recombination mechanism of the decomposition of adsorbed molecules. 10 references, 1 figure.

  15. Radiolysis of water molecules adsorbed on Al/sub 2/O/sub 3/, La/sub 2/O/sub 3/, Er/sub 2/O/sub 3/, BeO. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Garibov, A.A.; Melikzade, M.M.; Bakirov, M.Ya.; Ramazanova, M.Kh. (AN Azerbajdzhanskoj SSR, Baku. Sektor Radiatsionnykh Issledovanij)

    A study was made on kinetics of processes of hydrogen formation during gamma radiolysis of water in adsorbed state on the surface of Al/sub 2/O/sub 3/, La/sub 2/O/sub 3/, Er/sub 2/O/sub 3/ and BeO samples. It was revealed, that the presence of oxides causes the increase of the process rate and the yield of hydrogen during the heterogeneous radiolysis of water. It was established that beryllium oxide posseses the greatest catalytic activity among oxides investigated. In the presence of beryllium oxide the total yield of hydrogen molecules per 100 eV of absorbed energy attaines 4.4. Taking into consideration the energy absorbed by adsorbed water the yield is 210.

  16. Trichomonas gallinae Persistence in Four Water Treatments.

    Science.gov (United States)

    Purple, Kathryn E; Humm, Jacob M; Kirby, R Brian; Saidak, Christina G; Gerhold, Richard

    2015-07-01

    Trichomonas gallinae is a protozoan parasite commonly found in columbids, passerines, and several raptor species. Although T. gallinae is thought to spread between individuals and across species through shared water sources, little research has been conducted regarding the persistence of T. gallinae in the environment. To determine the persistence of T. gallinae in various communal water sources, we inoculated 1 × 10(6) trichomonads into 500 mL samples of distilled water, quarry water, bird bath water, and rain barrel water in two replicates. Aliquots of 0.5 mL were collected from each source at -1, 0, 15, 30, and 60 min; aliquots were incubated at 37 C and examined for trichomonads by light microscopy for five consecutive days. Live trichomonads were observed in all samples and at all sampling times except prior to inoculation (-1 min). The pH of water sources ranged from an average of 5.9 to 7.4 postsampling. Our findings indicate that T. gallinae can persist for up to 60 min in various water treatments and thus be infectious for birds drinking T. gallinae-contaminated water.

  17. Possible treatments for arsenic removal in Latin American waters for human consumption

    Energy Technology Data Exchange (ETDEWEB)

    Litter, Marta I., E-mail: litter@cnea.gov.a [Gerencia Quimica, Centro Atomico Constituyentes, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499, CP 1650, San Martin, Prov. de Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Av. Rivadavia 1917, CP 1033, Ciudad de Buenos Aires (Argentina); Instituto de Investigacion e Ingenieria Ambiental, Universidad Nacional de Gral. San Martin, Peatonal Belgrano 3563, 1o piso, CP 1650, San Martin, Prov. de Buenos Aires (Argentina); Morgada, Maria E. [Consejo Nacional de Investigaciones Cientificas y Tecnicas, Av. Rivadavia 1917, CP 1033, Ciudad de Buenos Aires (Argentina); Bundschuh, Jochen [University of Applied Sciences, Institute of Applied Research, Moltkestr. 30, 76133 Karlsruhe (Germany); Department of Earth Sciences, National Cheng Kung University, University Road, Tainan City 701, Taiwan (China)

    2010-05-15

    Considering the toxic effects of arsenic, the World Health Organization recommends a maximum concentration of 10 mug L{sup -1} of arsenic in drinking water. Latin American populations present severe health problems due to consumption of waters with high arsenic contents. The physicochemical properties of surface and groundwaters are different from those of other more studied regions of the planet, and the problem is still publicly unknown. Methods for arsenic removal suitable to be applied in Latin American waters are here summarized and commented. Conventional technologies (oxidation, coagulation-coprecipitation, adsorption, reverse osmosis, use of ion exchangers) are described, but emphasis is made in emergent decentralized economical methods as the use of inexpensive natural adsorbents, solar light technologies or biological treatments, as essential to palliate the situation in poor, isolated and dispersed populations of Latin American regions. - Low-cost techniques should be urgently investigated to remove arsenic in drinking water in poor disperse rural and urban Latin American populations.

  18. Obtaining and Application of New Cellulose- and Graphene Oxide-Based Adsorbents for Treatment of Industrial Waste Containing Heavy Metals

    Directory of Open Access Journals (Sweden)

    Beata Fryczkowska

    2017-11-01

    The studies show that doping of cellulose with graphene oxide clearly affects the physical properties of this biopolymer. GO improves the water absorption of CEL/GO composite cellulose granules only in the concentration above 0.05% w/w. For a concentration of 0.1% w/w of GO in cellulose, water absorption is increased by ~108% compared to pure cellulose granules. In addition, the use of dry and wet granules in the study changes their sorption properties with respect to all tested substances. Studies on test solutions have shown that the sorption of cellulose granules decreases with increasing molar mass of test compounds, in the following order: FeCl3, methylene blue (MB and bovine albumin (BSA. This means that the cellulose granules obtained in the experiment are made up of small micropores, which makes the diffusion of compounds of high molecular weight difficult. The best sorption results were obtained for ferric ions and amounted to 66-72% for FeCl3 solution, and ~92% for the wastewater that was sorbed on pure cellulose granules.

  19. Adsorption de l'eau dissoute dans les mélanges supercarburant-alcools en vue de leur stabilisation. Comparaison entre adsorbants classiques et résines échangeuses d'ions Adsorption of Dissolved Water in Premium-Fuel/Alcohol Blends with a View to Their Stabilization. Comparison Between Conventional Adsorbents and Ion-Exchange Resins

    Directory of Open Access Journals (Sweden)

    Bernasconi C.

    2006-11-01

    Full Text Available Une réponse possible au problème de la déstabilisation par démixtion des mélanges supercarburant-alcools est l'abaissement de leur teneur en eau par adsorption physique. La forte affinité pour l'eau des résines échangeuses d'ions de type polystyrène sulfonate permet d'envisager leur utilisation dans ce cas spécifique d'application. Le principal intérêt de ce nouveau matériau adsorbant est de pouvoir se régénérer avec des calories de bas niveau (100-120°C. Nous avons donc étudié, du point de vue capacité d'adsorption et cinétique d'adsorption, le comportement de cet adsorbant et comparé ses performances à celles d'adsorbants plus classiques tels que le silicagel, l'alumine et le tamis moléculaire 3 Å. Les formes ioniques de la résine mises en oeuvre sont les formes : K+, Na+ et Mg2+. Sur le plan de la capacité totale d'adsorption, la résine, quelle que soit sa forme ionique, présente des performances supérieures à celles de l'alumine et du silicagel. Seule la forme Mg2+ adsorbe autant d'eau que le tamis moléculaire. L'efficacité de la résine est sensible à la nature de l'alcool du mélange considéré et augmente selon la séquence méthanol A possible answer to the problem of destabilization by the segregation of premium-fuel/alcohol blends lies in decreasing their water content by physical adsorption. The strong affinity of water for ion-exchange resins of the polystyrene sulfonate type suggests their use for this specific application. The main advantage of this newadsorbent material is that it can be regenerated with low-level heat (100-120°C. We thus investigated the behavior of this adsorbent from the standpoint of its adsorption capacity and adsorption kinetics. Its performances were compared to those of more conventional adsorbents, such as silicagel, alumina and a 3Å molecular sieve. The ionic forms of the resin used are in the form of K+, Na+ and Mg2+. From the standpoint of total adsorption capacity

  20. Plant waste materials from restaurants as the adsorbents for dyes

    Directory of Open Access Journals (Sweden)

    Pavlović Marija D.

    2015-01-01

    Full Text Available This paper has demonstrated the valorization of inexpensive and readily available restaurant waste containing most consumed food and beverage residues as adsorbents for methylene blue dye. Coffee, tea, lettuce and citrus waste have been utilized without any pre-treatment, thus the adsorption capacities and dye removal efficiency were determined. Coffee waste showed highest adsorbent capacity, followed by tea, lettuce and citrus waste. The dye removal was more effective as dye concentration increases from 5 up to 60 mg/L. The favorable results obtained for lettuce waste have been especially encouraged, as this material has not been commonly employed for sorption purposes. Equilibrium data fitted very well in a Freundlich isotherm model, whereas pseudo-second-order kinetic model describes the process behavior. Restaurant waste performed rapid dye removal at no cost, so it can be adopted and widely used in industries for contaminated water treatment.

  1. Life cycle assessment of drinking water: comparing conventional water treatment, reverse osmosis and mineral water in glass and plastic bottles

    OpenAIRE

    Garfi, Marianna; Cadena, Erasmo; Sanchez Ramos, David; Ferrer Martí, Ivet

    2016-01-01

    This study evaluated the environmental impacts caused by drinking water consumption in Barcelona (Spain) using the Life Cycle Assessment (LCA) methodology. Five different scenarios were compared: 1) tap water from conventional drinking water treatment; 2) tap water from conventional drinking water treatment with reverse osmosis at the water treatment plant; 3) tap water from conventional drinking water treatment with domestic reverse osmosis; 4) mineral water in plastic bottles, and 5) minera...

  2. Effect of treatment with adsorbent resin on the volatile profile and physicochemical characteristics of clarified cashew apple juice

    Directory of Open Access Journals (Sweden)

    Adriana Dutra Sousa

    2013-12-01

    Full Text Available Increased preference for healthy and functional foods could be an opportunity to increase the consumption of clarified cashew apple juice. Given its level of fructose, glucose, and vitamin C, it can be used as a base in blends. However, its characteristic odor can interfere with the acceptance of these formulations, especially by consumers who are not familiar with cashew aroma. The aim of this study was to evaluate the effect of treatment with macroporous resins (FPA54, FPX66, XAD761, and XAD4 on the volatile profile and physicochemical characteristics of clarified cashew apple juice. After the treatment with the resins, the volatile profile was evaluated using solid-phase microextraction (SPME and gas chromatography/mass spectrometry (GC/MS. The physicochemical analyses performed were: pH, soluble solids (ºBrix, total titrable acidity, reducing sugars, and vitamin C. Gas chromatography analyses showed that XAD4 and FPX66 led to a reduction of the initial amount of volatile compounds to 14.05% and 15.72%, respectively. These two resins also did not affect the physicochemical characteristics of the clarified cashew apple juice.

  3. Cellulose nanomaterials in water treatment technologies.

    Science.gov (United States)

    Carpenter, Alexis Wells; de Lannoy, Charles-François; Wiesner, Mark R

    2015-05-05

    Cellulose nanomaterials are naturally occurring with unique structural, mechanical and optical properties. While the paper and packaging, automotive, personal care, construction, and textiles industries have recognized cellulose nanomaterials' potential, we suggest cellulose nanomaterials have great untapped potential in water treatment technologies. In this review, we gather evidence of cellulose nanomaterials' beneficial role in environmental remediation and membranes for water filtration, including their high surface area-to-volume ratio, low environmental impact, high strength, functionalizability, and sustainability. We make direct comparison between cellulose nanomaterials and carbon nanotubes (CNTs) in terms of physical and chemical properties, production costs, use and disposal in order to show the potential of cellulose nanomaterials as a sustainable replacement for CNTs in water treatment technologies. Finally, we comment on the need for improved communication and collaboration across the myriad industries invested in cellulose nanomaterials production and development to achieve an efficient means to commercialization.

  4. Cellulose Nanomaterials in Water Treatment Technologies

    Science.gov (United States)

    Carpenter, Alexis Wells; de Lannoy, Charles François; Wiesner, Mark R.

    2015-01-01

    Cellulose nanomaterials are naturally occurring with unique structural, mechanical and optical properties. While the paper and packaging, automotive, personal care, construction, and textiles industries have recognized cellulose nanomaterials’ potential, we suggest cellulose nanomaterials have great untapped potential in water treatment technologies. In this review, we gather evidence of cellulose nanomaterials’ beneficial role in environmental remediation and membranes for water filtration, including their high surface area-to-volume ratio, low environmental impact, high strength, functionalizability, and sustainability. We make direct comparison between cellulose nanomaterials and carbon nanotubes (CNTs) in terms of physical and chemical properties, production costs, use and disposal in order to show the potential of cellulose nanomaterials as a sustainable replacement for CNTs in water treatment technologies. Finally, we comment on the need for improved communication and collaboration across the myriad industries invested in cellulose nanomaterials production and development to achieve an efficient means to commercialization. PMID:25837659

  5. Water treatment plants assessment at Talkha power plant.

    Science.gov (United States)

    El-Sebaie, Olfat D; Abd El-Kerim, Ghazy E; Ramadan, Mohamed H; Abd El-Atey, Magda M; Taha, Sahr Ahmed

    2002-01-01

    Talkha power plant is the only power plant located in El-Mansoura. It generates electricity using two different methods by steam turbine and gas turbine. Both plants drew water from River Nile (208 m3 /h). The Nile raw water passes through different treatment processes to be suitable for drinking and operational uses. At Talkha power plant, there are two purification plants used for drinking water supply (100 m3/h) and for water demineralization supply (108 m3/h). This study aimed at studying the efficiency of the water purification plants. For drinking water purification plant, the annual River Nile water characterized by slightly alkaline pH (7.4-8), high annual mean values of turbidity (10.06 NTU), Standard Plate Count (SPC) (313.3 CFU/1 ml), total coliform (2717/100 ml), fecal coliform (0-2400/100 ml), and total algae (3 x 10(4) org/I). The dominant group of algae all over the study period was green algae. The blue green algae was abundant in Summer and Autumn seasons. The pH range, and the annual mean values of turbidity, TDS, total hardness, sulfates, chlorides, nitrates, nitrites, fluoride, and residual chlorine for purified water were in compliance with Egyptian drinking water standards. All the SPC recorded values with an annual mean value of 10.13 CFU/1 ml indicated that chlorine dose and contact time were not enough to kill the bacteria. However, they were in compliance with Egyptian decree (should not exceed 50 CFU/1 ml). Although the removal efficiency of the plant for total coliform and blue green algae was high (98.5% and 99.2%, respectively), the limits of the obtained results with an annual mean values of 40/100 ml and 15.6 org/l were not in compliance with the Egyptian decree (should be free from total coliform, fecal coliform and blue green algae). For water demineralization treatment plant, the raw water was characterized by slightly alkaline pH. The annual mean values of conductivity, turbidity, and TDS were 354.6 microS/cm, 10.84 NTU, and 214

  6. Treatment of Oil & Gas Produced Water.

    Energy Technology Data Exchange (ETDEWEB)

    Dwyer, Brian P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-02-01

    Production of oil and gas reserves in the New Mexico Four Corners Region results in large volumes of "produced water". The common method for handling the produced water from well production is re-injection in regulatory permitted salt water disposal wells. This is expensive (%7E $5/bbl.) and does not recycle water, an ever increasingly valuable commodity. Previously, Sandia National Laboratories and several NM small business tested pressure driven membrane-filtration techniques to remove the high TDS (total dissolved solids) from a Four Corners Coal Bed Methane produced water. Treatment effectiveness was less than optimal due to problems with pre-treatment. Inadequate pre-treatment allowed hydrocarbons, wax and biological growth to foul the membranes. Recently, an innovative pre-treatment scheme using ozone and hydrogen peroxide was pilot tested. Results showed complete removal of hydrocarbons and the majority of organic constituents from a gas well production water. ACKNOWLEDGEMENTS This report was made possible through funding from the New Mexico Small Business Administration (NMSBA) Program at Sandia National Laboratories. Special thanks to Juan Martinez and Genaro Montoya for guidance and support from project inception to completion. Also, special thanks to Frank McDonald, the small businesses team POC, for laying the ground work for the entire project; Teresa McCown, the gas well owner and very knowledgeable- fantastic site host; Lea and Tim Phillips for their tremendous knowledge and passion in the oil & gas industry.; and Frank Miller and Steve Addleman for providing a pilot scale version of their proprietary process to facilitate the pilot testing.

  7. Thermophilic aerobic post treatment of anaerobically pretreated paper process water

    NARCIS (Netherlands)

    Vogelaar, J.C.T.

    2002-01-01

    Thermophilic waste- or process water treatment increases in importance as industries shift from end-of-pipe treatment towards integrated process water treatment. The need for process water treatment becomes evident as the levels of pollutants in industrial water

  8. Development and Optimum Composition of Locally Developed Potable Water Treatment Tablets

    Directory of Open Access Journals (Sweden)

    Josiah Oladele BABATOLA

    2009-07-01

    Full Text Available Current high level of energy cost and operational cost of membrane technologies and couple with difficulties in obtaining chemicals for potable water treatment give rooms for development of local substance and low cost adsorbents for water treatment. This paper presents a follow-up study on an earlier work in which some water treatment Tablets were produced and tested. The current work was directed at establishing the optimum composition of the tablets. Alum, calcium hypochlorite and lime were combined in proportion and made into pastes and tablets. Residual chlorine contents of the tablets were determined. The quality of stream water samples treated with the tablets was measured by chlorine content, pH and turbidity removal. It is concluded that the best composition is one part alum, two parts hypochlorite and three parts lime and this produced treated water pH of 7.8, chlorine residual of 5.0 mg/l and settled water turbidity 3.0 NTU. The product is aimed for use in rural communities to reduce rampaging death from water borne diseases.

  9. Produced water treatment methods for SAGD

    Energy Technology Data Exchange (ETDEWEB)

    Minnich, K. [Veolia Water Solutions and Technologies, Mississauga, ON (Canada)

    2008-07-01

    Produced water treatment methods for steam assisted gravity drainage (SAGD) processes were presented. Lime softening is used to remove sludge before weak acid cation processes. However, the process is not reliable in cold climates, and disposal of the sludge is now posing environmental problems in Alberta. High pH MVC evaporation processes use sodium hydroxide (NaOH) additions to prevent silica scaling. However the process produces silica wastes that are difficult to dispose of. The sorption slurry process was designed to reduce the use of caustic soda and develop a cost-effective method of disposing evaporator concentrates. The method produces 98 per cent steam quality for SAGD injection. Silica is sorbed onto crystals in order to prevent silica scaling. The evaporator concentrate from the process is suitable for on- and off-site deep well disposal. The ceramic membrane process was designed to reduce the consumption of chemicals and improve the reliability of water treatment processes. The ion exchange desilication process uses 80 per cent less power and produces 80 per cent fewer CO{sub 2} emissions than MVC evaporators. A comparative operating cost evaluation of various electric supply configurations and produced water treatment processes was also included, as well as an analysis of produced water chemistry. tabs., figs.

  10. Disordered adsorbate phases

    Science.gov (United States)

    Rys, Franz S.

    1985-04-01

    The occurrence of disordered phases at low temperatures in adsorbed monolayers, as shown recently in a domain wall model, is discussed, the main results are summarized and some relevant experimental systems are mentionned.

  11. Molecular Adsorber Coating

    Science.gov (United States)

    Straka, Sharon; Peters, Wanda; Hasegawa, Mark; Hedgeland, Randy; Petro, John; Novo-Gradac, Kevin; Wong, Alfred; Triolo, Jack; Miller, Cory

    2011-01-01

    A document discusses a zeolite-based sprayable molecular adsorber coating that has been developed to alleviate the size and weight issues of current ceramic puck-based technology, while providing a configuration that more projects can use to protect against degradation from outgassed materials within a spacecraft, particularly contamination-sensitive instruments. This coating system demonstrates five times the adsorption capacity of previously developed adsorber coating slurries. The molecular adsorber formulation was developed and refined, and a procedure for spray application was developed. Samples were spray-coated and tested for capacity, thermal optical/radiative properties, coating adhesion, and thermal cycling. Work performed during this study indicates that the molecular adsorber formulation can be applied to aluminum, stainless steel, or other metal substrates that can accept silicate-based coatings. The coating can also function as a thermal- control coating. This adsorber will dramatically reduce the mass and volume restrictions, and is less expensive than the currently used molecular adsorber puck design.

  12. Water Treatment Systems for Long Spaceflights

    Science.gov (United States)

    FLynn, Michael T.

    2012-01-01

    Space exploration will require new life support systems to support the crew on journeys lasting from a few days to several weeks, or longer. These systems should also be designed to reduce the mass required to keep humans alive in space. Water accounts for about 80 percent of the daily mass intake required to keep a person alive. As a result, recycling water offers a high return on investment for space life support. Water recycling can also increase mission safety by providing an emergency supply of drinking water, where another supply is exhausted or contaminated. These technologies also increase safety by providing a lightweight backup to stored supplies, and they allow astronauts to meet daily drinking water requirements by recycling the water contained in their own urine. They also convert urine into concentrated brine that is biologically stable and nonthreatening, and can be safely stored onboard. This approach eliminates the need to have a dedicated vent to dump urine overboard. These needs are met by a system that provides a contaminant treatment pouch, referred to as a urine cell or contaminant cell, that converts urine or another liquid containing contaminants into a fortified drink, engineered to meet human hydration, electrolyte, and caloric requirements, using a variant of forward osmosis (FO) to draw water from a urine container into the concentrated fortified drink as part of a recycling stage. An activated carbon pretreatment removes most organic molecules. Salinity of the initial liquid mix (urine plus other) is synergistically used to enhance the precipitation of organic molecules so that activated carbon can remove most of the organics. A functional osmotic bag is then used to remove inorganic contaminants. If a contaminant is processed for which the saline content is different than optimal for precipitating organic molecules, the saline content of the liquid should be adjusted toward the optimal value for that contaminant. A first urine

  13. Are the reduction and oxidation properties of nitrocompounds dissolved in water different from those produced when adsorbed on a silica surface? A DFT M05-2X computational study.

    Science.gov (United States)

    Sviatenko, Liudmyla K; Isayev, Olexandr; Gorb, Leonid; Hill, Frances C; Leszczynska, Danuta; Leszczynski, Jerzy

    2015-05-30

    The reduction and oxidation properties of four nitrocompounds (trinitrotoluene [TNT], 2,4-dinitrotoluene, 2,4-dinitroanisole, and 5-nitro-2,4-dihydro-3H-1,2,4-triazol-3-one [NTO]) dissolved in water as compared with the same properties for compounds adsorbed on a silica surface were studied. To consider the influence of adsorption, cluster models were developed at the M05/tzvp level. A hydroxylated silica (001) surface was chosen to represent a key component of soil. The PCM(Pauling) and SMD solvation models were used to model water bulk influence. The following properties were analyzed: electron affinity, ionization potential, reduction Gibbs free energy, oxidation Gibbs free energy, and reduction and oxidation potentials. It was found that adsorption and solvation decrease gas phase electron affinity, ionization potential, and Gibbs free energy of reduction and oxidation, and thus, promote redox transformation of nitrocompounds. However, in case of solvation, the changes are more significant than for adsorption. This means that nitrocompounds dissolved in water are easier to transform by reduction or oxidation than adsorbed ones. Among the considered compounds, TNT was found to be the most reactive in an electron attachment process and the least reactive for an electron detachment transformation. During ionization, a deprotonation of adsorbed NTO was found to occur. © 2015 Wiley Periodicals, Inc.

  14. Zirconium-based highly porous metal-organic framework (MOF-545) as an efficient adsorbent for vortex assisted-solid phase extraction of lead from cereal, beverage and water samples.

    Science.gov (United States)

    Tokalıoğlu, Şerife; Yavuz, Emre; Demir, Selçuk; Patat, Şaban

    2017-12-15

    In this study, zirconium-based highly porous metal-organic framework, MOF-545, was synthesized and characterized. The surface area of MOF-545 was found to be 2192m 2 /g. This adsorbent was used for the first time as an adsorbent for the vortex assisted-solid phase extraction of Pb(II) from cereal, beverage and water samples. Lead in solutions was determined by FAAS. The optimal experimental conditions were as follows: the amount of MOF-545, 10mg; pH of sample, 7; adsorption and elution time, 15min; and elution solvent, 2mL of 1molL -1 HCl. Under the optimal conditions of the method, the limit of detection, preconcentration factor and precision as RSD% were found to be 1.78μgL -1 , 125 and 2.6%, respectively. The adsorption capacity of the adsorbent for lead was found to be 73mgg -1 . The method was successfully verified by analyzing two certified reference materials (BCR-482 Lichen and SPS-WW1 Batch 114) and spiked chickpea, bean, wheat, lentil, cherry juice, mineral water, well water and wastewater samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Using Zn/Al layered double hydroxide as a novel solid-phase extraction adsorbent to extract polycyclic aromatic hydrocarbons at trace levels in water samples prior to the determination of gas chromatography-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yan-Long [Wuhan University of Technology, School of Resources and Environmental Engineering, Wuhan (China); Shandong Academy of Sciences, Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong Province, Analysis and Test Center, Jinan (China); Zhou, Jia-Bin [Wuhan University of Technology, School of Resources and Environmental Engineering, Wuhan (China); Zhao, Ru-Song; Chen, Xiang-Feng [Shandong Academy of Sciences, Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong Province, Analysis and Test Center, Jinan (China)

    2012-09-15

    This paper demonstrates, for the first time, the great potential of using Zn/Al layered double hydroxide intercalated sodium dodecyl benzene sulfonate (Zn/Al-SDBS-LDH) as a solid-phase extraction (SPE) material in the extraction of persistent organic pollutants prior to the determination of gas chromatography-mass spectrometry in environmental water samples. Zn/Al-SDBS-LDH, a relatively inexpensive and simply prepared material, was synthesized and used as a SPE adsorbent to quantitatively determine the concentration of five polycyclic aromatic hydrocarbons (PAHs) in environmental water samples. Factors affecting extraction efficiency, such as, eluent type, eluent volume, flow rate of sample, sample volume, and amount of adsorbent, were investigated and optimized in detail. Experimental results indicate that there is an excellent linear relationship between peak area and the concentration of PAHs over the range of 5-500 ng L{sup -1}, and the precisions (relative standard deviation (RSD)) were 2.5-6.3 % under the optimum conditions. Based on the ratio of chromatographic signal-to-base line noise (S/N = 3), the limits of detection could reach 1.2-3.2 ng L{sup -1}. This novel method was successfully applied to the analysis of PAHs in environmental water samples. As such, we show here that the use of Zn/Al-SDBS-LDH as SPE adsorbent materials, coupled with gas chromatography-mass spectrometry, is an excellent improvement in the routine analysis of PAHs at trace levels in the environment. (orig.)

  16. Deep water treatment of mine water by double stage filtration

    Energy Technology Data Exchange (ETDEWEB)

    Grigoryuk, E.V.; Semenenko, B.A.; Grishchenko, O.V.

    1983-06-01

    Presented was a double stage water filter used for treatment of mine water from underground coal mines in the Donbass. An experimental unit of the filter was developed by DonUGI. It consists of two chambers: the initial filtration chamber filled with claydite (grain size from 1.8 to 2.5 mm) and the chamber for repeated filtration filled with quartz sand (grain size from 0.8 to 1.6 mm). Productivity of the filter ranges from 25 to 30 m/SUP/3/h. The maximum content of solids suspended in mine water filtered by the DonUGI system had to be lower than 200 mg/l. Reagent consumption was about 20 mg/l. One filtration cycle was at least 6 h long. Filter cleaning by a fresh water stream flowing in the opposite direction took 8 min. Content of suspended matter in water after filtration was below 1.5 mg/l. Filter design is shown in a scheme. Advantages of filter use were compared to a system of settling tanks and single stage filtration systems. (In Russian)

  17. Linking water treatment practices and fish welfare

    DEFF Research Database (Denmark)

    Zubiaurre, Claire; Pedersen, Lars-Flemming

    2016-01-01

    optimizing treatment protocols a challenge. Continuous low-dose applications seem to be a promising solution. In this preliminary study behavioral response was used to assess potential correlations with PAA dosage. A behavioral change or response is not necessarily an indication of compromised welfare....... Supportive enzymatic, biochemical and physiological biomarkers can be used along with gill and epidermal histological measures to evaluate the effects on water treatment regimens. The ultimate goal is to define the therapeutic window where fish welfare is not compromised.PAA is among the few disinfectants...

  18. Low cost adsorbents for the removal of organic pollutants from wastewater.

    Science.gov (United States)

    Ali, Imran; Asim, Mohd; Khan, Tabrez A

    2012-12-30

    Water pollution due to organic contaminants is a serious issue because of acute toxicities and carcinogenic nature of the pollutants. Among various water treatment methods, adsorption is supposed as the best one due to its inexpensiveness, universal nature and ease of operation. Many waste materials used include fruit wastes, coconut shell, scrap tyres, bark and other tannin-rich materials, sawdust and other wood type materials, rice husk, petroleum wastes, fertilizer wastes, fly ash, sugar industry wastes blast furnace slag, chitosan and seafood processing wastes, seaweed and algae, peat moss, clays, red mud, zeolites, sediment and soil, ore minerals etc. These adsorbents have been found to remove various organic pollutants ranging from 80 to 99.9%. The present article describes the conversion of waste products into effective adsorbents and their application for water treatment. The possible mechanism of adsorption on these adsorbents has also been included in this article. Besides, attempts have been made to discuss the future perspectives of low cost adsorbents in water treatment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Selection of sorbent for removing pesticides during water treatment.

    Science.gov (United States)

    Ignatowicz, Katarzyna

    2009-09-30

    This paper presents research on phenoxyacid pesticides removal using sorption methods on activated carbons. It was noted, that physico-chemical properties of adsorbent and adsorbate as well as parameters of the process have influence on adsorption of pesticides, derivatives of phenoxyacetic acid on carbon. The experimental data were analyzed by the Freundlich isotherm. The best for remove from water on carbon NP-5 was 2,4-D. Equilibrium data fitted well with the Freundlich model with maximum adsorption capacity of NP-5 carbon. The exemplary sorption capacity at equilibrium concentration 10 mg L(-1) were: 2,4-D 70 mg g(-1), MCPA 2 mg g(-1), MCPP 0.5 mg g(-1). The results indicated that coconut shell-based NP-5 carbon is most effective for the adsorption of phenoxyacetic acid from aqueous solutions.

  20. Photocatalysis: Oxidative Processes in Water Treatment

    Directory of Open Access Journals (Sweden)

    Roman V. Prihod'ko

    2013-01-01

    Full Text Available The efficiency of various homogeneous and heterogeneous systems photocatalytic processes destructive oxidation of organic compounds of different classes is considered. It is shown that photocatalytic methods can significantly increase the speed and depth (up to complete mineralization of decomposition processes of toxicants. The use of photocatalysis (PC in the creation of low-power water treatment technologies is a promising direction in addressing environmental problems of the hydrosphere.

  1. STUDY ON WASTE WATER TREATMENT PLANTS

    Directory of Open Access Journals (Sweden)

    Mariana DUMITRU

    2015-04-01

    Full Text Available Biogas is more and more used as an alternative source of energy, considering the fact that it is obtained from waste materials and it can be easily used in cities and rural communities for many uses, between which, as a fuel for households. Biogas has many energy utilisations, depending on the nature of the biogas source and the local demand. Generally, biogas can be used for heat production by direct combustion, electricity production by fuel cells or micro-turbines, Combined Hest and Power generation or as vehicle fuel. In this paper we search for another uses of biogas and Anaerobe Digestion substrate, such as: waste water treatment plants and agricultural wastewater treatment, which are very important in urban and rural communities, solid waste treatment plants, industrial biogas plants, landfill gas recovery plants. These uses of biogas are very important, because the gas emissions and leaching to ground water from landfill sites are serious threats for the environment, which increase more and more bigger during the constant growth of some human communities. That is why, in the developed European countries, the sewage sludge is treated by anaerobe digestion, depending on national laws. In Romania, in the last years more efforts were destined to use anaerobe digestion for treating waste waters and management of waste in general. This paper can be placed in this trend of searching new ways of using with maximum efficiency the waste resulted in big communities.

  2. Produced water treatment using polymeric resins; Resinas polimericas para tratamento da agua produzida

    Energy Technology Data Exchange (ETDEWEB)

    Louvisse, Ana Maria Travalloni; Freire, Norma de Oliveira [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas; Queiros, Yure Gomes de Carvalho; Silva, Carla Michele Frota da; Barros, Cintia Chagas; Lucas, Elizabeth Fernandes [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Inst. de Macromoleculas

    2008-07-01

    The treatment and disposal of oily waters from oil production and refining processes represent an important technological pass for attendance of the ambient legislation and to the politics of the Cia of search of the environmental excellence. The reuse or reinjection of the co-produced water has been considered an interesting strategical alternative, however, the water quality requirement for these processes demands a pretreatment step, considering the exit effluent from primary and secondary treatment processes currently used. This work presents resulted of the polymeric resin development for tertiary treatment of oily waters with low oil and grasses content and fine solids, including the dissolved fraction. These resins can adsorb, in reversible form, organic components. Its high adsorption capacity is determined by the polarity, superficial area, range of porosity and a wide distribution of particle size and pore. Another important characteristic is the possibility of its use in some cycles of work due to its weak forces of interaction between the contaminants and the surface of the resin. Regeneration can be carried through of diverse forms, including the use of solvent, with or without the variation of temperature and/or pH. The gotten results indicated a high resin adsorption capacity, with concentrated oily water treatment volume 10,000 times the volume of resin used. (author)

  3. 40 CFR 141.83 - Source water treatment requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Source water treatment requirements... water treatment requirements. Systems shall complete the applicable source water monitoring and....86, and 141.88) by the following deadlines. (a) Deadlines for completing source water treatment steps...

  4. 7 CFR 305.22 - Hot water immersion treatment schedules.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Hot water immersion treatment schedules. 305.22... Hot water immersion treatment schedules. (a) T102-d. (1) Fruit must be grown and treated in Hawaii. (2) Fruit must be submerged at least 4 inches below the water's surface in a hot water immersion treatment...

  5. Addition of a Magnetite Layer onto a Polysulfone Water Treatment Membrane to Enhance Virus Removal

    Science.gov (United States)

    Raciny, Isabel

    The applicability of low-pressure membranes systems in distributed (point of use) water treatment is hindered by, among other things, their inability to remove potentially harmful viruses and ions via size exclusion. According to the USEPA and the Safe Drinking Water Act, drinking water treatment processes must be designed for 4-log virus removal. Batch experiments using magnetite nanoparticle (nano-Fe3O4) suspensions and water filtration experiments with Polysulfone (PSf) membranes coated with nano-Fe3O 4 were conducted to assess the removal of a model virus (bacteriophage MS2). The membranes were coated via a simple filtration protocol. Unmodified membranes were a poor adsorbent for MS2 bacteriophage with less than 0.5-log removal, whereas membranes coated with magnetite nanoparticles exhibited a removal efficiency exceeding 99.99% (4-log). Thus, a cartridge of PSf membranes coated with nano-Fe3O4 particles could be used to remove viruses from water. Such membranes showed negligible iron leaching into the filtrate, thus obviating concern about colored water. Further research is needed to reduce the loss of water flux caused by coating.

  6. EFFICIENCY OF REMOVING BIOGENIC COMPOUNDS IN WATER TREATMENT

    OpenAIRE

    Artur Jachimowski

    2017-01-01

    The aim of the study was to determine the effectiveness of removal of biogenic compounds from water during the treatment process in water treatment plants of Municipal Water Supply and Sewerage Company in Cracow. The selected water quality indicators were analyzed before and after the treatment process in 2007 - 2014. The research was carried out in waters taken from plants that differed in treatment and production. In the analyzed technological systems it was stated that the biggest objectio...

  7. Phosphorylated cellulose triacetate-silica composite adsorbent for recovery of heavy metal ion.

    Science.gov (United States)

    Srivastava, Niharika; Thakur, Amit K; Shahi, Vinod K

    2016-01-20

    Phosphorylated cellulose triacetate (CTA)/silica composite adsorbent was prepared by acid catalyzed sol-gel method using an inorganic precursor (3-aminopropyl triethoxysilane (APTEOS)). Reported composite adsorbent showed comparatively high adsorption capacity for Ni(II) in compare with different heavy metal ions (Cu(2+), Ni(2+), Cd(2+) and Pb(2+)). For Ni(II) adsorption, effect of time, temperature, pH, adsorbent dose and adsorbate concentration were investigated; different kinetic models were also evaluated. Thermodynamic parameters such as ΔG°, ΔH° and ΔS° were also estimated and equilibrium adsorption obeyed Langmuir and Freundlich isotherms. Developed adsorbent exhibited about 78.8% Ni(II) adsorption at pH: 6 and a suitable candidate for the removal of Ni(II) ions from wastewater. Further, about 65.5% recovery of adsorbed Ni(II) using EDTA solution was demonstrated, which suggested effective recycling of the functionalized beads would enable it to be used in the treatment of contaminated water in industry. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. 207 EFFECTS OF HOT AND COLD WATER PRE- TREATMENTS ...

    African Journals Online (AJOL)

    no significant difference in the number of seeds that emerged from the cold water treatment (á = 0.05), while treatment with hot water showed significant differences among the treatment times. (á =0.05). Treatment of a. senegal seeds with hot water for 10 minutes gave the highest number of emerged seeds (mean, 7.50) ...

  9. Chitin Adsorbents for Toxic Metals: A Review

    Directory of Open Access Journals (Sweden)

    Ioannis Anastopoulos

    2017-01-01

    Full Text Available Wastewater treatment is still a critical issue all over the world. Among examined methods for the decontamination of wastewaters, adsorption is a promising, cheap, environmentally friendly and efficient procedure. There are various types of adsorbents that have been used to remove different pollutants such as agricultural waste, compost, nanomaterials, algae, etc., Chitin (poly-β-(1,4-N-acetyl-d-glucosamine is the second most abundant natural biopolymer and it has attracted scientific attention as an inexpensive adsorbent for toxic metals. This review article provides information about the use of chitin as an adsorbent. A list of chitin adsorbents with maximum adsorption capacity and the best isotherm and kinetic fitting models are provided. Moreover, thermodynamic studies, regeneration studies, the mechanism of adsorption and the experimental conditions are also discussed in depth.

  10. Selective electrochemical reduction of CO2 to CO with a cobalt chlorin complex adsorbed on multi-walled carbon nanotubes in water.

    Science.gov (United States)

    Aoi, Shoko; Mase, Kentaro; Ohkubo, Kei; Fukuzumi, Shunichi

    2015-06-25

    Electrocatalytic reduction of CO2 occurred efficiently using a glassy carbon electrode modified with a cobalt(II) chlorin complex adsorbed on multi-walled carbon nanotubes at an applied potential of -1.1 V vs. NHE to yield CO with a Faradaic efficiency of 89% with hydrogen production accounting for the remaining 11% at pH 4.6.

  11. A review of water treatment membrane nanotechnologies

    KAUST Repository

    Pendergast, MaryTheresa M.

    2011-01-01

    Nanotechnology is being used to enhance conventional ceramic and polymeric water treatment membrane materials through various avenues. Among the numerous concepts proposed, the most promising to date include zeolitic and catalytic nanoparticle coated ceramic membranes, hybrid inorganic-organic nanocomposite membranes, and bio-inspired membranes such as hybrid protein-polymer biomimetic membranes, aligned nanotube membranes, and isoporous block copolymer membranes. A semi-quantitative ranking system was proposed considering projected performance enhancement (over state-of-the-art analogs) and state of commercial readiness. Performance enhancement was based on water permeability, solute selectivity, and operational robustness, while commercial readiness was based on known or anticipated material costs, scalability (for large scale water treatment applications), and compatibility with existing manufacturing infrastructure. Overall, bio-inspired membranes are farthest from commercial reality, but offer the most promise for performance enhancements; however, nanocomposite membranes offering significant performance enhancements are already commercially available. Zeolitic and catalytic membranes appear reasonably far from commercial reality and offer small to moderate performance enhancements. The ranking of each membrane nanotechnology is discussed along with the key commercialization hurdles for each membrane nanotechnology. © 2011 The Royal Society of Chemistry.

  12. Preparation of novel nano-adsorbent based on organic-inorganic hybrid and their adsorption for heavy metals and organic pollutants presented in water environment.

    Science.gov (United States)

    Jin, Xinliang; Yu, Cui; Li, Yanfeng; Qi, Yongxin; Yang, Liuqing; Zhao, Guanghui; Hu, Huaiyuan

    2011-02-28

    The nanocomposites based on organic-inorganic hybrid have been attracting much attention due to their potential applications used as new type of functional materials, such as colloidal stabilizers, electro-optical devices, and nanocomposites materials. The organic-inorganic hybrid of poly(acrylic acid-acrylonitrile)/attapulgite, P(A-N)/AT nanocomposites, were prepared by using in situ polymerization and composition of acrylic acid (AA) and acrylonitrile (AN) onto modified attapulgite (AT) nanoparticles. The resulting P(A-N)/AT nanocomposites were transformed into novel nano-adsorbent of poly(acrylic acid-acryloamidoxime)/attapulgite by further functionalization, i.e. P(A-O)/AT nano-adsorbent. The adsorption properties of P(A-O)/AT toward metal ions were determined, and the results indicated that the adsorbents with nanocomposite structure held a good of selectivity to Pb(2+) among numerous metal ions. The maximum removal capacity of Pb(2+) was up to 109.9 mg/g and it is notable to see that the adsorption removal of P(A-O)/AT nano-adsorbent for Pb(2+) could achieve more than 96.6% when the initial concentration of Pb(2+) was 120.0 mg/l. The kinetics, isotherm models, and conductivity were introduced to study the adsorption mechanism of P(A-O)/AT for Pb(2+) and it was concluded that it could be chemisorptions process and the best coordination form took place when AO:AA:Pb(2+) = 1:1:1. In addition, after simply treated with CTAB, P(A-O)/AT nano-adsorbent showed better adsorption properties for phenol than the same kinds of materials. Copyright © 2010 Elsevier B.V. All rights reserved.

  13. Supercritical water oxidation treatment of textile sludge.

    Science.gov (United States)

    Zhang, Jie; Wang, Shuzhong; Li, Yanhui; Lu, Jinling; Chen, Senlin; Luo, XingQi

    2017-08-01

    In this work, we studied the supercritical water oxidation (SCWO) of the textile sludge, the hydrothermal conversion of typical textile compounds and the corrosion properties of stainless steel 316. Moreover, the influence mechanisms of NaOH during these related processes were explored. The results show that decomposition efficiency for organic matter in liquid phase of the textile sludge was improved with the increment of reaction temperature or oxidation coefficient. However, the organic substance in solid phase can be oxidized completely in supercritical water. Serious coking occurred during the high pressure water at 250-450°C for the Reactive Orange 7, while at 300 and 350°C for the polyvinyl alcohol. The addition of NaOH not only accelerated the destruction of organic contaminants in the SCWO reactor, but effectively inhibited the dehydration conversion of textile compounds during the preheating process, which was favorable for the treatment system of textile sludge. The corrosion experiment results indicate that the stainless steel 316 could be competent for the body materials of the reactor and the heat exchangers. Furthermore, there was prominent enhancement of sodium hydroxide for the corrosion resistance of 316 in subcritical water. On the contrary the effect was almost none during SCWO.

  14. A novel, integrated treatment system for coal waste waters. Quarterly report, June 2, 1994--September 1, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H.Y.; Srinivasan, K.R.

    1994-12-01

    The aims of this study are to develop, characterize and optimize a novel treatment scheme that would be effective simultaneously against the toxic organics and the heavy metals present in coal conversion waste waters. A specific goal of the study is to remove and recover cationic and anionic heavy metals from aqueous solutions and coal conversion waste waters using modified-clay adsorbents developed in this study. We have carried out multi-step adsorption/desorption studies with these adsorbents which indicate that modified-smectites can be repeatedly used up to 5 times with less than 15% loss in their potency. Thus, it would appear that the DT coatings on DT-modified clays are quite stable. Continuous leaching experiments have been undertaken to verify the stability of adsorbed DT on DT-modified smectites, HCDT and MONT-DT. Potentiometric titrations and ESA measurements at different time intervals have been used respectively to determine the surface charge density and the sign of surface charge of DT-modified smectites. Our results show that, even after 44 hours of continuous leaching of DT-modified smectites by deionized water, the surface charge density as measured by pH titration is lower by less than 10% of its initial value. Further more, the surface charge remains positive in the pH range of 9.5-3.0. These results are in agreement with our earlier results based on Ninhydrin assay and organic carbon analysis of the same DT-modified smectites.

  15. Optimized alumina coagulants for water treatment

    Science.gov (United States)

    Nyman, May D [Albuquerque, NM; Stewart, Thomas A [Albuquerque, NM

    2012-02-21

    Substitution of a single Ga-atom or single Ge-atom (GaAl.sub.12 and GeAl.sub.12 respectively) into the center of an aluminum Keggin polycation (Al.sub.13) produces an optimal water-treatment product for neutralization and coagulation of anionic contaminants in water. GaAl.sub.12 consistently shows .about.1 order of magnitude increase in pathogen reduction, compared to Al.sub.13. At a concentration of 2 ppm, GaAl.sub.12 performs equivalently to 40 ppm alum, removing .about.90% of the dissolved organic material. The substituted GaAl.sub.12 product also offers extended shelf-life and consistent performance. We also synthesized a related polyaluminum chloride compound made of pre-hydrolyzed dissolved alumina clusters of [GaO.sub.4Al.sub.12(OH).sub.24(H.sub.2O).sub.12].sup.7+.

  16. Pilot scale test of a produced water-treatment system for initial removal of organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Enid J [Los Alamos National Laboratory; Kwon, Soondong [UT-AUSTIN; Katz, Lynn [UT-AUSTIN; Kinney, Kerry [UT-AUSTIN

    2008-01-01

    A pilot-scale test to remove polar and non-polar organics from produced water was performed at a disposal facility in Farmington NM. We used surfactant-modified zeolite (SMZ) adsorbent beds and a membrane bioreactor (MBR) in combination to reduce the organic carbon content of produced water prior to reverse osmosis (RO). Reduction of total influent organic carbon (TOC) to 5 mg/L or less is desirable for efficient RO system operation. Most water disposed at the facility is from coal-bed gas production, with oil production waters intermixed. Up to 20 gal/d of produced water was cycled through two SMZ adsorbent units to remove volatile organic compounds (BTEX, acetone) and semivolatile organic compounds (e.g., napthalene). Output water from the SMZ units was sent to the MBR for removal of the organic acid component of TOC. Removal of inorganic (Mn and Fe oxide) particulates by the SMZ system was observed. The SMZ columns removed up to 40% of the influent TOC (600 mg/L). BTEX concentrations were reduced from the initial input of 70 mg/L to 5 mg/L by the SMZ and to an average of 2 mg/L after the MBR. Removal rates of acetate (input 120-170 mg/L) and TOC (input up to 45 mg/L) were up to 100% and 92%, respectively. The water pH rose from 8.5 to 8.8 following organic acid removal in the MBR; this relatively high pH was likely responsible for observed scaling of the MBR internal membrane. Additional laboratory studies showed the scaling can be reduced by metered addition of acid to reduce the pH. Significantly, organic removal in the MBR was accomplished with a very low biomass concentration of 1 g/L throughout the field trial. An earlier engineering evaluation shows produced water treatment by the SMZ/MBR/RO system would cost from $0.13 to $0.20 per bbl at up to 40 gpm. Current estimated disposal costs for produced water are $1.75 to $4.91 per bbl when transportation costs are included, with even higher rates in some regions. Our results suggest that treatment by an SMZ

  17. Palladium-Zeolite nanofiber as an effective recyclable catalyst membrane for water treatment.

    Science.gov (United States)

    Choi, Jungsu; Chan, Sophia; Yip, Garriott; Joo, Hyunjong; Yang, Heejae; Ko, Frank K

    2016-09-15

    Zeolite is an exciting natural material due to its unique capability of ammonium nitrogen (NH3N) adsorption in water. In this study, multifunctional hybrid composites of zeolite/palladium (Ze/Pd) on polymer nanofiber membranes were fabricated and explored for sustainable contaminant removal. SEM and XRD demonstrated that zeolite and palladium nanoparticles were uniformly distributed and deposited on the nanofibers. NH3N recovery rate was increased from 23 to 92% when palladium coated zeolite was embedded on the nanofiber. Multifunctional nanofibers of Ze/Pd membranes were able to adsorb NH3N on the zeolites placed on the surface of fibers and palladium catalysts were capable of selective oxidation of NH3N to N2 gas. The cycling of NH3N adsorption-oxidation, high flux, hydrophilicity, and flexibility of the membrane makes it a strong candidate for water treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Integrated modeling of ozonation for optimization of drinking water treatment

    NARCIS (Netherlands)

    van der Helm, A.W.C.

    2007-01-01

    Drinking water treatment plants automation becomes more sophisticated, more on-line monitoring systems become available and integration of modeling environments with control systems becomes easier. This gives possibilities for model-based optimization. In operation of drinking water treatment

  19. Water treatment: A scalable graphene-based membrane

    Science.gov (United States)

    Vlassiouk, Ivan V.

    2017-11-01

    An improved industrial manufacturability has been achieved for a hybrid water-treatment membrane that exhibits high water permeance, prolonged high salt and dye rejection under cross-flow conditions and better resistance to chlorine treatment.

  20. Assessment of didecyldimethylammonium chloride as a ballast water treatment method

    NARCIS (Netherlands)

    van Slooten, Cees; Buma, Anita; Peperzak, Louis

    Ballast water-mediated transfer of aquatic invasive species is considered a major threat to marine biodiversity, marine industry and human health. A ballast water treatment is needed to comply with International Maritime Organization (IMO) ballast water discharge regulations. Didecyldimethylammonium

  1. Assessment of didecyldimethylammonium chloride as a ballast water treatment method

    NARCIS (Netherlands)

    van Slooten, C.; Peperzak, L.; Buma, A.G.J.

    2015-01-01

    Ballast water-mediated transfer of aquatic invasive species is considered a major threat to marine biodiversity, marine industry and human health. A ballast water treatment is needed to comply with International Maritime Organization (IMO) ballast water discharge regulations. Didecyldimethylammonium

  2. Trace determination of chromium(VI) in environmental water samples using innovative thermally reduced graphene (TRG) modified SiO₂ adsorbent for solid phase extraction and UV-vis spectrophotometry.

    Science.gov (United States)

    Sereshti, Hassan; Farahani, Mina Vasheghani; Baghdadi, Majid

    2016-01-01

    An innovative thermally reduced graphene (TRG) modified silica-supported 3-aminopropyltriethoxysilane (SiO2-APTES) composite was synthesized and characterized using Fourier transform-infrared spectroscopy (FT-IR) and scanning electron microscopy SEM techniques. The adsorbent was then used in the solid phase extraction (SPE) of Cr (VI) as the Cr (VI)-diphenylcarbazide (DPC) complex with the subsequent measurement by UV-vis spectrophotometry. The adsorbent surface was activated by adding sodium dodecyl sulfate (SDS) to the sample solution. The effect of the main experimental parameters such as type and volume of the extraction solvent, pH, dosage of DPC, SDS, the adsorbent, time of the extraction, and salt concentration on the extraction efficiency were investigated and optimized. A linear dynamic range of 1.3-40 ng mL(-1) with a satisfactory determination coefficient (R(2)) of 0.9930 was obtained. A detection limit of 0.4 ng mL(-1) Cr (VI) was attained when a sample volume of 25 mL was used. Intraday and inter-day precisions were obtained equal to 2.3% and 7.9%, respectively. The enrichment factor (EF) was calculated to be equal to 167. The technique was applied successfully to the determination of Cr (VI) at trace levels in tap, river, sewage and ground water samples and the relative recoveries of the added chromium were in the range of 92.6-109.9%. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Efficacy of conventional drinking water treatment processes in ...

    African Journals Online (AJOL)

    2013-10-07

    Oct 7, 2013 ... statistical evidence could be displayed to suggest effective removal of geosmin in this conventional water treatment plant. With good ... drinking water treatment processes can effectively remove problem-causing phytoplankton as well as their associated ..... increasing the cost of water treatment significantly.

  4. Preparation of magnetic graphene/mesoporous silica composites with phenyl-functionalized pore-walls as the restricted access matrix solid phase extraction adsorbent for the rapid extraction of parabens from water-based skin toners.

    Science.gov (United States)

    Feng, Jianan; He, Xinying; Liu, Xiaodan; Sun, Xueni; Li, Yan

    2016-09-23

    In this work, phenyl-functionalized magnetic graphene/mesoporous silica composites (MG-mSiO2-Ph) were prepared and applied as restricted access matrix solid phase extraction (RAM-SPE) adsorbents to determine the parabens in commercially available retail cosmetics. MG-mSiO2-Ph composites were synthesized by a surfactant-mediated co-condensation reaction in which mesoporous silica with phenyl-functionalized pore-walls was coated on a magnetic graphene sheet. The obtained nano-composites were proven to be of sufficient quality for an ideal RAM-SPE adsorbent with a large specific surface area of 369m(2)g(-1), uniform mesopores of 2.8nm, and special phenyl-functionalized pore-walls. Parabens, such as methyl paraben, ethyl paraben and propyl paraben, were extracted from water-based skin toners using one step of the RAM-SPE and were then analysed by a HPLC-DAD system. The SPE conditions were optimized by studying the parameters, such as the adsorbent amount, elution solvent type, adsorption time and desorption time, that influence the extraction efficiency. For each analyte, there were good linearities of approximately 0.10-120μgmL(-1) with determination coefficients (R(2))>0.995. The sensitivity was as low as 0.01-0.025μgmL(-1) for the LOD, and the percent recoveries were 98.37-105.84%. The intra-day and inter-day RSDs were 1.44-6.11% (n=6) and 3.12-11.70% (n=6), respectively. The results indicated that this method with novel RAM-SPE adsorbents is sensitive and convenient. The results also offered an attractive alternative for the extraction and determination of paraben preservatives in a complex matrix, such as cosmetics. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Bovine serum albumin-Cu(II) hybrid nanoflowers: An effective adsorbent for solid phase extraction and slurry sampling flame atomic absorption spectrometric analysis of cadmium and lead in water, hair, food and cigarette samples

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, Erkan [Department of Chemistry, Faculty of Sciences, Erciyes University, Kayseri 38039 (Turkey); Ocsoy, Ismail [Department of Analytical Chemistry, Faculty of Pharmacy, Erciyes University, Kayseri 38039 (Turkey); Nanotechnology Research Center (ERNAM), Erciyes University, Kayseri 38039 (Turkey); Ozdemir, Nalan [Department of Chemistry, Faculty of Sciences, Erciyes University, Kayseri 38039 (Turkey); Soylak, Mustafa, E-mail: soylak@erciyes.edu.tr [Department of Chemistry, Faculty of Sciences, Erciyes University, Kayseri 38039 (Turkey)

    2016-02-04

    Herein, the synthesis of bovine serum albumin-Cu(II) hybrid nanoflowers (BSA-NFs) through the building blocks of bovine serum albumin (BSA) and copper(II) ions in phosphate buffered saline (PBS) and their use as adsorbent for cadmium and lead ions are reported. The BSA-NFs, for the first time, were efficiently utilized as novel adsorbent for solid phase extraction (SPE) of cadmium and lead ions in water, food, cigarette and hair samples. The method is based on the separation and pre-concentration of Cd(II) and Pb(II) by BSA-NFs prior to determination by slurry analysis via flame atomic absorption spectrometry (FAAS). The analytes were adsorbed on BSA-NFs under the vortex mixing and then the ion-loaded slurry was separated and directly introduced into the flame AAS nebulizer by using a hand-made micro sample introduction system to eliminate a number of drawbacks. The effects of analytical key parameters, such as pH, amount of BSA-NFs, vortexing time, sample volume, and matrix effect of foreign ions on adsorbing of Cd(II) and Pb(II) were systematically investigated and optimized. The limits of detection (LODs) for Cd(II) and Pb(II) were calculated as 0.37 μg L{sup −1} and 8.8 μg L{sup −1}, respectively. The relative standard deviation percentages (RSDs) (N = 5) for Cd(II) and Pb(II) were 7.2%, and 5.0%, respectively. The accuracy of the developed procedure was validated by the analysis of certified reference materials (TMDA-53.3 Fortified Water, TMDA-70 Fortified Water, SPS-WW2 Waste Water, NCSDC-73349 Bush Branches and Leaves) and by addition/recovery analysis. The quantitative recoveries were obtained for the analysis of certified reference materials and addition/recovery tests. The method was successfully applied to the analysis of cadmium and lead in water, food, cigarette and hair samples. - Highlights: • The synthesis of bovine serum albumin-Cu(II) hybrid nanoflowers is reported. • The nanoflowers were utilized for solid phase microextraction of

  6. Bovine serum albumin-Cu(II) hybrid nanoflowers: An effective adsorbent for solid phase extraction and slurry sampling flame atomic absorption spectrometric analysis of cadmium and lead in water, hair, food and cigarette samples.

    Science.gov (United States)

    Yilmaz, Erkan; Ocsoy, Ismail; Ozdemir, Nalan; Soylak, Mustafa

    2016-02-04

    Herein, the synthesis of bovine serum albumin-Cu(II) hybrid nanoflowers (BSA-NFs) through the building blocks of bovine serum albumin (BSA) and copper(II) ions in phosphate buffered saline (PBS) and their use as adsorbent for cadmium and lead ions are reported. The BSA-NFs, for the first time, were efficiently utilized as novel adsorbent for solid phase extraction (SPE) of cadmium and lead ions in water, food, cigarette and hair samples. The method is based on the separation and pre-concentration of Cd(II) and Pb(II) by BSA-NFs prior to determination by slurry analysis via flame atomic absorption spectrometry (FAAS). The analytes were adsorbed on BSA-NFs under the vortex mixing and then the ion-loaded slurry was separated and directly introduced into the flame AAS nebulizer by using a hand-made micro sample introduction system to eliminate a number of drawbacks. The effects of analytical key parameters, such as pH, amount of BSA-NFs, vortexing time, sample volume, and matrix effect of foreign ions on adsorbing of Cd(II) and Pb(II) were systematically investigated and optimized. The limits of detection (LODs) for Cd(II) and Pb(II) were calculated as 0.37 μg L(-)(1) and 8.8 μg L(-)(1), respectively. The relative standard deviation percentages (RSDs) (N = 5) for Cd(II) and Pb(II) were 7.2%, and 5.0%, respectively. The accuracy of the developed procedure was validated by the analysis of certified reference materials (TMDA-53.3 Fortified Water, TMDA-70 Fortified Water, SPS-WW2 Waste Water, NCSDC-73349 Bush Branches and Leaves) and by addition/recovery analysis. The quantitative recoveries were obtained for the analysis of certified reference materials and addition/recovery tests. The method was successfully applied to the analysis of cadmium and lead in water, food, cigarette and hair samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Superparamagnetic core-shells anchored onto graphene oxide grafted with phenylethyl amine as a nano-adsorbent for extraction and enrichment of organophosphorus pesticides from fruit, vegetable and water samples.

    Science.gov (United States)

    Mahpishanian, Shokouh; Sereshti, Hassan; Baghdadi, Majid

    2015-08-07

    A novel adsorbent composed of silica coated magnetic microparticles (Fe3O4@SiO2) and graphene oxide (GO) functionalized with phenylethyl amine (PEA) was synthesized and characterized using Fourier transform-infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), and CHN elemental analysis techniques. The adsorbent (Fe3O4@SiO2@GO-PEA) was then used in a magnetic solid phase extraction (MSPE) of six organophosphorous pesticides (OPPs) including methyl parathion, fenitrothion, methidathion, ethion, methyl azinphos and coumaphos prior to gas chromatography-nitrogen phosphorus detection (GC-NPD). The fabricated adsorbent combines the advantages of superior adsorption capability of modified GO and magnetic separability of magnetite microparticles to provide high adsorption capacity, and easy isolation from sample solutions. The main experimental parameters affecting the extraction recovery of OPPs including extraction time, pH, adsorbent dosage, salt concentration, and desorption conditions were investigated and optimized. Under the optimal conditions, linear responses were obtained in the concentration range of 0.06-200μgL(-1) with the determination coefficients (R(2)) between 0.9945 and 0.9996. The limits of detection were from 0.02 to 0.1μgL(-1) and the intraday and inter-day relative standard deviations (RSDs) were less than 4.8 and 6.4%, respectively. The method was successfully applied for determination of the OPPs in apple, grape, pear, bell pepper, celery and water samples. The obtained recoveries were in the range of 90.4-108.0% (RSDs=1.9-6.6%, n=3) for fruits and vegetables, and 94.6-104.2% (RSDs=2.0-4.8%, n=3) for water samples. The excellent extraction performance of the adsorbent can be attributed to its structure characteristics where the phenyl rings of PEA grafted on the GO nanosheets are accessible to interact effectively with OPPs via delocalized π-electron system. Copyright © 2015 Elsevier B.V. All

  8. EFFICIENCY OF REMOVING BIOGENIC COMPOUNDS IN WATER TREATMENT

    Directory of Open Access Journals (Sweden)

    Artur Jachimowski

    2017-08-01

    Full Text Available The aim of the study was to determine the effectiveness of removal of biogenic compounds from water during the treatment process in water treatment plants of Municipal Water Supply and Sewerage Company in Cracow. The selected water quality indicators were analyzed before and after the treatment process in 2007 - 2014. The research was carried out in waters taken from plants that differed in treatment and production. In the analyzed technological systems it was stated that the biggest objections raised the concentration of nitrates, the average content of which is higher in treated water in three plants: Rudawa, Dłubnia and Bielany.

  9. Costs of water treatment due to diminished water quality: A case study in Texas

    Science.gov (United States)

    Dearmont, David; McCarl, Bruce A.; Tolman, Deborah A.

    1998-04-01

    The cost of municipal water treatment due to diminished water quality represents an important component of the societal costs of water pollution. Here the chemical costs of municipal water treatment are expressed as a function of raw surface water quality. Data are used for a 3-year period for 12 water treatment plants in Texas. Results show that when regional raw water contamination is present, the chemical cost of water treatment is increased by 95 per million gallons (per 3785 m3) from a base of 75. A 1% increase in turbidity is shown to increase chemical costs by 0.25%.

  10. A novel, integrated treatment system for coal waste waters. Quarterly report, March 2, 1994--June 1, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H.Y. [Univ. of Michigan, Ann Arbor, MI (United States); Wang, H.Y.; Srinivasan, K.R.

    1994-09-01

    The aims of this study are to develop, characterize and optimize a novel treatment scheme that would be effective simultaneously against the toxic organics and the heavy metals present in coal conversion waste waters. A specific goal of the study is to remove and recover cationic and anionic heavy metals from aqueous solutions and coal conversion waste waters using modified-clay adsorbents developed in this study. To this end, a multi-step adsorption/desorption process has been carried out with hectorite-CBDA-DT (HCDT) as the adsorbent and Cr(VI) as the adsorbate. Adsorption was carried out at pH 4.0 in 0.02 M buffer, while desorption was effected at the same pH and in the same buffer with either 0.5 M NaCl or 0.02 M Na{sub 2}SO{sub 4} as the desorbates. Multi-step involves cycling the same adsorbent through these two sets of operating conditions with a washing step after each adsorption/desorption sequence. The authors results indicate that, during the first two cycles, the potency of the adsorbent remains unchanged, but it diminishes after the third and the fourth cycles. The total decrease in potency is, however, only 15% even after 4 cycles of adsorption/desorption. Addition of 20% isopropyl alcohol (IPA) to the reaction medium, however, diminishes the potency even more after 4 cycles of adsorption and desorption. Both the desorbates yielded identical results, and the overall mass balance on Cr(VI) was between 95 and 102%. Continuous leaching experiments on HCDT revealed that DT bound to HCDT is mobilized to the extent of only 10% after 44 hrs in aqueous medium while in 20% IPA-water mixtures the extent of dissolution of DT from the surface is close to 16%. Thus, the loss of potency of HCDT is attributed partly to the loss of DT from the surface and partly to the incomplete washing of the adsorbent between each adsorption/desorption step.

  11. Advanced water treatment as a tool in water scarcity management

    DEFF Research Database (Denmark)

    Harremoes, Poul

    2000-01-01

    The water resource is under increasing pressure, both from the increase in population and from the wish to improve the living standards of the individual. Water scarcity is defined as the situation where demand is greater than the resource. Water scarcity has two distinctly different dimensions......: water availability and water applicability. The availability is a question of quantitative demand relative to resource. The applicability is a question of quality suitability for the intended use of the water. There is a significant difference in this regard with respect to rural versus urban use...... of water. In the former case, the water is lost by evaporation and polluted. In the latter case, the water is not lost but heavily polluted. With increasing scarcity, the value of water and the need for controls increase. In this situation, water reuse becomes an option that has been considered exotic...

  12. Fe3O4@ionic liquid@methyl orange nanoparticles as a novel nano-adsorbent for magnetic solid-phase extraction of polycyclic aromatic hydrocarbons in environmental water samples.

    Science.gov (United States)

    Liu, Xiaofei; Lu, Xin; Huang, Yong; Liu, Chengwei; Zhao, Shulin

    2014-02-01

    A novel nano-adsorbent, Fe3O4@ionic liquid@methyl orange nanoparticles (Fe3O4@IL@MO NPs), was prepared for magnetic solid-phase extraction (MSPE) of polycyclic aromatic hydrocarbons (PAHs) in environmental water samples. The Fe3O4@IL@MO NPs were synthesized by self-assembly of the ionic liquid 1-octadecyl-3-methylimidazolium bromide (C18mimBr) and methyl orange (MO) onto the surface of Fe3O4 silica magnetic nanoparticles, as confirmed by infrared spectroscopy, ultraviolet-visible spectroscopy and superconducting quantum interface device magnetometer. The extraction performance of Fe3O4@IL@MO NPs as a nano-adsorbent was evaluated by using five PAHs, fluorene (FLu), anthracene (AnT), pyrene (Pyr), benzo(a)anthracene (BaA) and benzo(a)pyrene (BaP) as model analytes. Under the optimum conditions, detection limits in the range of 0.1-2 ng/L were obtained by high performance liquid chromatography-fluorescence detection (HPLC-FLD). This method has been successfully applied for the determination of PAHs in environmental water samples by using the MSPE-HPLC-FLD. The recoveries for the five PAHs tested in spiked real water samples were in the range of 80.4-104.0% with relative standard deviations ranging from 2.3 to 4.9%. © 2013 Published by Elsevier B.V.

  13. Bacterial Cyanuric Acid Hydrolase for Water Treatment.

    Science.gov (United States)

    Yeom, Sujin; Mutlu, Baris R; Aksan, Alptekin; Wackett, Lawrence P

    2015-10-01

    Di- and trichloroisocyanuric acids are widely used as water disinfection agents, but cyanuric acid accumulates with repeated additions and must be removed to maintain free hypochlorite for disinfection. This study describes the development of methods for using a cyanuric acid-degrading enzyme contained within nonliving cells that were encapsulated within a porous silica matrix. Initially, three different bacterial cyanuric acid hydrolases were compared: TrzD from Acidovorax citrulli strain 12227, AtzD from Pseudomonas sp. strain ADP, and CAH from Moorella thermoacetica ATCC 39073. Each enzyme was expressed recombinantly in Escherichia coli and tested for cyanuric acid hydrolase activity using freely suspended or encapsulated cell formats. Cyanuric acid hydrolase activities differed by only a 2-fold range when comparing across the different enzymes with a given format. A practical water filtration system is most likely to be used with nonviable cells, and all cells were rendered nonviable by heat treatment at 70°C for 1 h. Only the CAH enzyme from the thermophile M. thermoacetica retained significant activity under those conditions, and so it was tested in a flowthrough system simulating a bioreactive pool filter. Starting with a cyanuric acid concentration of 10,000 μM, more than 70% of the cyanuric acid was degraded in 24 h, it was completely removed in 72 h, and a respike of 10,000 μM cyanuric acid a week later showed identical biodegradation kinetics. An experiment conducted with water obtained from municipal swimming pools showed the efficacy of the process, although cyanuric acid degradation rates decreased by 50% in the presence of 4.5 ppm hypochlorite. In total, these experiments demonstrated significant robustness of cyanuric acid hydrolase and the silica bead materials in remediation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  14. The low-throughput protein A adsorber: an immune modulatory device. Hypothesis for the mechanism of action in the treatment of rheumatoid arthritis.

    Science.gov (United States)

    Brunner, Jürgen; Kern, Peter M; Gaipl, Udo S; Munoz, Luis E; Voll, Reinhard E; Kalden, Joachim R; Wiesenhutter, Craig W; Herrmann, Martin

    2005-01-01

    To achieve specific removal of pathogenic antibodies (Ab) or immune complexes (IC), several adsorbers have been developed. We discuss the mode of action of low-throughput staphylococcal protein A (SPA) immunoadsorption. The SPA-based Prosorba apheresis is likely to modify some of the autoantibodies (autoAb) or IC. The low-throughput adsorber showed very limited adsorption capacity of circulating autoAb and/or circulating IC. Besides changes of humoral diagnostic parameters, cellular changes could be observed in the Prosorba-treated patients. These changes were rather similar to those that have been observed in a patient successfully treated with Ab against tumor necrosis factor alpha. We propose an adsorber-catalyzed conversion of small, tissue-penetrating, scarcely detectable, non-complement-binding, proinflammatory IgG-rheumatoid factor (RF)-based IC into the more readily phagocytosed species of IC: intermediate-sized, partially cryoprecipitable, non-tissue penetrating IC that are opsonized with complement. These IC are rather short-lived and could quickly be cleared by the body's scavenging system.

  15. Optimization of Parameters for Purification of Jatropha Curcas Based Biodiesel Using Organic Adsorbents

    OpenAIRE

    Banga, sangita; Varshney, Pradeep; Kumar, Naveen; Pal, Madan

    2016-01-01

    This paper discusses purification of biodiesel by using organic adsorbents instead of traditional water washing technique. The efficiency of different organic adsorbents under different conditions was compared with each other as well as traditional water washed biodiesel for the purification of Jatropha Curcas based transesterified biodiesel. The proposed methodologies were based on the use of Amberlite BD10 DRY, Purolite PD 206and Tulison T-45BD as adsorbents. The response of each adsorbent ...

  16. Theoretical insight of physical adsorption for a single-component adsorbent+adsorbate system: I. Thermodynamic property surfaces.

    Science.gov (United States)

    Chakraborty, Anutosh; Saha, Bidyut Baran; Ng, Kim Choon; Koyama, Shigeru; Srinivasan, Kandadai

    2009-02-17

    Thermodynamic property surfaces for a single-component adsorbent+adsorbate system are derived and developed from the viewpoint of classical thermodynamics, thermodynamic requirements of chemical equilibrium, Gibbs law, and Maxwell relations. They enable us to compute the entropy and enthalpy of the adsorbed phase, the isosteric heat of adsorption, specific heat capacity, and the adsorbed phase volume thoroughly. These equations are very simple and easy to handle for calculating the energetic performances of any adsorption system. We have shown here that the derived thermodynamic formulations fill up the information gap with respect to the state of adsorbed phase to dispel the confusion as to what is the actual state of the adsorbed phase. We have also discussed and established the temperature-entropy diagrams of (i) CaCl2-in-silica gel+water system for cooling applications, and (ii) activated carbon (Maxsorb III)+methane system for gas storage.

  17. Theoretical Insight of Physical Adsorption for a Single-Component Adsorbent + Adsorbate System: I. Thermodynamic Property Surfaces

    KAUST Repository

    Chakraborty, Anutosh

    2009-02-17

    Thermodynamic property surfaces for a single-component adsorbent + adsorbate system are derived and developed from the viewpoint of classical thermodynamics, thermodynamic requirements of chemical equilibrium, Gibbs law, and Maxwell relations. They enable us to compute the entropy and enthalpy of the adsorbed phase, the isosteric heat of adsorption, specific heat capacity, and the adsorbed phase volume thoroughly. These equations are very simple and easy to handle for calculating the energetic performances of any adsorption system. We have shown here that the derived thermodynamic formulations fill up the information gap with respect to the state of adsorbed phase to dispel the confusion as to what is the actual state of the adsorbed phase. We have also discussed and established the temperature-entropy diagrams of (i) CaCl 2-in-silica gel + water system for cooling applications, and (ii) activated carbon (Maxsorb III) + methane system for gas storage. © Copyright 2009 American Chemical Society.

  18. Design and performance prediction of a new generation adsorption chiller using composite adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Gong, L.X., E-mail: carrie@sjtu.edu.c [Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, 800 Dong chuan Road, Shanghai 200240 (China); Wang, R.Z.; Xia, Z.Z.; Chen, C.J. [Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, 800 Dong chuan Road, Shanghai 200240 (China)

    2011-06-15

    Research highlights: {yields} Composite adsorbent 'employing lithium chloride in silica gel' and water as working pair. {yields} A new type adsorbent bed is used to accommodate the composite adsorbent. {yields} A dynamic model of the adsorption chiller is built. {yields} The coefficient of performance (COP) and the cooling capacity will be improved. -- Abstract: This paper presents a novel adsorption chiller using composite adsorbent 'employing lithium chloride in silica gel' as adsorbent and water as adsorbate. A new type adsorbent bed is used to accommodate the composite adsorbent. The mass recovery between two adsorbent beds usually results in the adsorbate unbalance. So a novel auto water makeup unite is used to solve the problem. A dynamic model of the adsorption chiller is built based on the adsorption isotherms to predict the performance. The simulation result shows that the coefficient of performance (COP) and the cooling capacity will increase by using this new composite adsorbent. When the temperatures of hot water inlet, cooling water inlet, and chilled water inlet are 363, 303 and 293 K, COP will be 0.43, and the cooling capacity will be 5.295 kW. Also operation strategy is optimized. Different temperatures of hot water inlet, cooling water inlet and chilling water inlet will result in different COP and cooling capacity.

  19. Selenium contaminated waters: An overview of analytical methods, treatment options and recent advances in sorption methods.

    Science.gov (United States)

    Santos, Sílvia; Ungureanu, Gabriela; Boaventura, Rui; Botelho, Cidália

    2015-07-15

    Selenium is an essential trace element for many organisms, including humans, but it is bioaccumulative and toxic at higher than homeostatic levels. Both selenium deficiency and toxicity are problems around the world. Mines, coal-fired power plants, oil refineries and agriculture are important examples of anthropogenic sources, generating contaminated waters and wastewaters. For reasons of human health and ecotoxicity, selenium concentration has to be controlled in drinking-water and in wastewater, as it is a potential pollutant of water bodies. This review article provides firstly a general overview about selenium distribution, sources, chemistry, toxicity and environmental impact. Analytical techniques used for Se determination and speciation and water and wastewater treatment options are reviewed. In particular, published works on adsorption as a treatment method for Se removal from aqueous solutions are critically analyzed. Recent published literature has given particular attention to the development and search for effective adsorbents, including low-cost alternative materials. Published works mostly consist in exploratory findings and laboratory-scale experiments. Binary metal oxides and LDHs (layered double hydroxides) have presented excellent adsorption capacities for selenium species. Unconventional sorbents (algae, agricultural wastes and other biomaterials), in raw or modified forms, have also led to very interesting results with the advantage of their availability and low-cost. Some directions to be considered in future works are also suggested. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Drinking water treatment plant costs and source water quality: An updated case study (2013-2016)

    Science.gov (United States)

    Watershed protection can play an important role in producing safe drinking water. However, many municipalities and drinking water treatment plants (DWTPs) lack the information on the potential benefits of watershed protection as an approach to improving source water quality. This...

  1. Water treatment for fossil fuel power generation - technology status report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-02-07

    This technology status report focuses on the use of water treatment technology in fossil fuel power plants. The use of polymeric ion exchange resins for deionization of water, the currently preferred use of ion exchange for economically treating water containing low dissolved salts, the use of low pressure high-flux membranes, membrane microfiltration, and reverse osmosis are discussed. Details are given of the benefits of the technologies, water use at power plants, the current status of water treatment technologies, and the potential for future developments, along with power plant market trends and potentials, worldwide developments, and UK capabilities in water treatment plant design and manufacturing.

  2. Availability Analysis of Chemicals for Water Treatment: An ...

    African Journals Online (AJOL)

    Availability Analysis of Chemicals for Water Treatment: An Application to Edo and Anambra State Water Utilities Boards. ... assist water utility decision makers during current and subsequent periods in order to determine an optimal policy for uninterrupted supply of chemicals required at the treatment plants at minimum cost.

  3. Optimization of Drinking Water Treatment Processes Using Artificial ...

    African Journals Online (AJOL)

    Drinking water treatment is the process of removing microorganisms and solid from water through different methods such as coagulation and filtration. Artificial neural network (ANN) was developed for process and cost optimization of drinking water treatment processes. Results obtained from ANN model showed that ANN ...

  4. Fixed-biofilm reactors applied to waste water treatment and aquacultural water recirculating systems

    NARCIS (Netherlands)

    Bovendeur, J.

    1989-01-01

    Fixed-biofilm waste water treatment may be regarded as one of the oldest engineered biological waste water treatment methods. With the recent introduction of modern packing materials, this type of reactor has received a renewed impuls for implementation in a wide field of water treatment.

    In

  5. Trace Cd(II, Pb(II and Ni(II ions extraction and preconcentration from different water samples by using Ghezeljeh montmorillonite nanoclay as a natural new adsorbent

    Directory of Open Access Journals (Sweden)

    Zahra hassanzadeh Siahpoosh

    2017-01-01

    Full Text Available This investigate presents the extraction-preconcentration of Lead, Cadmium, and Nickel ions from water samples using Ghezeljeh montmorillonite nanoclay or “Geleh-Sar-Shoor” (means head-washing clay as a natural and native new adsorbent in batch single element systems. The Ghezeljeh clay is categorized by using Fourier Transform Infrared Spectroscopy (FT-IR, Scanning Electron Microscopy-Energy Dispersive Spectrometer Operating (SEM-EDS, X-ray Diffractometry (XRD, X-ray Fluorescence (XRF, Cation Exchange Capacity (CEC measurements, Surface property valuation (SBET by the BET method from nitrogen adsorption isotherms and Zeta potential. According to BET theory, the specific surface area of Ghezeljeh nanoclay was computed as 19.8 m2 g-1 whereas the cation exchange capacity was determined as 150 meq (100 g-1. The results of XRD, FT-IR, XRF, zeta potential, BET surface area and CEC of the Ghezeljeh clay confirm that montmorillonite is the dominant mineral phase. Based on SEM images of clay, it can be seen that the distance between the plates is nm level. For all three ions, the limit of detection, the limit of quantification, dynamic linear range, preconcentration factor, and the adsorption capacity were obtained. The result of several interfering ions was considered. The Ghezeljeh nanoclay as a new adsorbent and experimental method were effectively used for the extraction of heavy metals (Lead, Cadmium, and Nickel in a variety of real water samples.

  6. Water quality modelling and optimisation of wastewater treatment ...

    African Journals Online (AJOL)

    2016-10-04

    Oct 4, 2016 ... Using this model, it was demonstrated that water quality standards can be met at all monitoring points at a minimum cost by simultaneously optimising treatment levels at each treatment plant. Keywords: instream water quality, mixed integer optimisation, wastewater treatment levels, Streeter-Phelps.

  7. Evaluation of two methods in controlling dental treatment water contamination.

    Science.gov (United States)

    Bansal, Ritu; Puttaiah, Raghunath; Harris, Robert; Reddy, Anil

    2011-03-01

    Dental unit water systems are contaminated with biofilms that amplify bacterial counts in dental treatment water in excess of a million colony forming units per milliliter (cfu/ml). The Centers for Disease Control and Prevention and the American Dental Association have agreed that the maximum allowable contamination of dental treatment water not exceed 500 cfu/ml. This study was conducted to evaluate two protocols in controlling contamination of dental unit water systems and dental treatment water. Both methods used an antimicrobial self-dissolving chlorine dioxide (ClO₂) tablet at a high concentration (50 ppm) to shock the dental unit water system biofilms initially followed by periodic exposure. To treat dental treatment source water for patient care, 3 parts per million (ppm) ClO₂ in municipal/tap water was compared to use of a citrus botanical extract dissolved in municipal water. Heterotrophic microbial counts of effluent water and laser scanning confocal microscopy were performed to evaluate effects of the two treatments. Results from this study indicated that both treatments were effective in controlling biofilm contamination and reducing heterotrophic plate counts water system and effects of low-grade chemicals used on composite bonding to dentin and enamel is warranted before translation from efficacy studies to common clinical use. This study provides evidence-based information of using two methods of controlling dental treatment water contamination. The study was conducted in a clinical practice setting in an active dental clinic and the results are meaningful to a clinician who is interested in providing safe dental treatment water for patient care. Dental waterline biofilms, Dental treatment water contamination control, Chlorine dioxide, Emulsifiers, Heterotrophic plate counts, Laser scanning confocal microscopy. How to cite this article: Bansal R, Puttaiah R, Harris R, Reddy A. Evaluation of Two Methods in Controlling Dental Treatment Water

  8. Influence of water quality on the embodied energy of drinking water treatment.

    Science.gov (United States)

    Santana, Mark V E; Zhang, Qiong; Mihelcic, James R

    2014-01-01

    Urban water treatment plants rely on energy intensive processes to provide safe, reliable water to users. Changes in influent water quality may alter the operation of a water treatment plant and its associated energy use or embodied energy. Therefore the objective of this study is to estimate the effect of influent water quality on the operational embodied energy of drinking water, using the city of Tampa, Florida as a case study. Water quality and water treatment data were obtained from the David L Tippin Water Treatment Facility (Tippin WTF). Life cycle energy analysis (LCEA) was conducted to calculate treatment chemical embodied energy values. Statistical methods including Pearson's correlation, linear regression, and relative importance were used to determine the influence of water quality on treatment plant operation and subsequently, embodied energy. Results showed that influent water quality was responsible for about 14.5% of the total operational embodied energy, mainly due to changes in treatment chemical dosages. The method used in this study can be applied to other urban drinking water contexts to determine if drinking water source quality control or modification of treatment processes will significantly minimize drinking water treatment embodied energy.

  9. Magnetic adsorbent constructed from the loading of amino functionalized Fe3O4 on coordination complex modified polyoxometalates nanoparticle and its tetracycline adsorption removal property study

    Science.gov (United States)

    Ou, Jinzhao; Mei, Mingliang; Xu, Xinxin

    2016-06-01

    A magnetic polyoxometalates based adsorbent has been synthesized successfully through the loading of amino functionalized Fe3O4 (NH2-Fe3O4) on nanoparticle of a coordination complex modified polyoxometalates (CC/POMNP). FTIR illustrate there exist intense hydrogen bonds between NH2-Fe3O4 and CC/POMNP, which keep the stability of this adsorbent. At room temperature, this adsorbent exhibits ferromagnetic character with saturation magnetization of 8.19 emu g-1, which provides prerequisite for fast magnetic separation. Water treatment experiment illustrates this POM based magnetic adsorbent exhibits high adsorption capacity on tetracycline. The adsorption process can be described well with Temkin model, which illustrates the interaction between adsorbent and tetracycline plays the dominated role in tetracycline removal. The rapid, high efficient tetracycline adsorption ability suggests this POM based magnetic adsorbent exhibits promising prospect in medical and agriculture waste water purification. A magnetic polyoxometalates based adsorbent, which exhibits excellent tetracycline adsorption removal property has been synthesized through the loading of NH2-Fe3O4 on coordination complex modified polyoxometalates

  10. The Uranium from Seawater Program at the Pacific Northwest National Laboratory: Overview of Marine Testing, Adsorbent Characterization, Adsorbent Durability, Adsorbent Toxicity, and Deployment Studies

    Energy Technology Data Exchange (ETDEWEB)

    Gill, Gary A.; Kuo, Li-Jung; Janke, Chris J.; Park, Jiyeon; Jeters, Robert T.; Bonheyo, George T.; Pan, Horng-Bin; Wai, Chien; Khangaonkar, Tarang; Bianucci, Laura; Wood, Jordana R.; Warner, Marvin G.; Peterson, Sonja; Abrecht, David G.; Mayes, Richard T.; Tsouris, Costas; Oyola, Yatsandra; Strivens, Jonathan E.; Schlafer, Nicholas J.; Addleman, R. Shane; Chouyyok, Wilaiwan; Das, Sadananda; Kim, Jungseung; Buesseler, Ken; Breier, Crystal; D’Alessandro, Evan

    2016-02-07

    The Pacific Northwest National Laboratory’s (PNNL) Marine Science Laboratory (MSL) located along the coast of Washington State is evaluating the performance of uranium adsorption materials being developed for seawater extraction under realistic marine conditions with natural seawater. Two types of exposure systems were employed in this program: flow-through columns for testing of fixed beds of individual fibers and pellets and a recirculating water flume for testing of braided adsorbent material. Testing consists of measurements of the adsorption of uranium and other elements from seawater as a function of time, typically 42 to 56 day exposures, to determine the adsorbent capacity and adsorption rate (kinetics). Analysis of uranium and other trace elements collected by the adsorbents was conducted following strong acid digestion of the adsorbent with 50% aqua regia using either Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) or Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The ORNL 38H adsorbent had a 56 day adsorption capacity of 3.30 ± 0.68 g U/ kg adsorbent (normalized to a salinity of 35 psu), a saturation adsorption capacity of 4.89 ± 0.83 g U/kg of adsorbent material (normalized to a salinity of 35 psu) and a half-saturation time of 28 ± 10 days. The AF1 adsorbent material had a 56 day adsorption capacity of 3.9 ± 0.2 g U/kg adsorbent material (normalized to a salinity of 35 psu), a saturation capacity of 5.4 ± 0.2 g U/kg adsorbent material (normalized to a salinity of 35 psu) and a half saturation time of 23 ± 2 days. The ORNL amidoxime-based adsorbent materials are not specific for uranium, but also adsorb other elements from seawater. The major doubly charged cations in seawater (Ca and Mg) account for a majority of the cations adsorbed (61% by mass and 74% by molar percent). For the ORNL AF1 adsorbent material, U is the 4th most abundant element adsorbed by mass and 7th most abundant by molar percentage

  11. Microbiological treatment of oil mill waste waters

    Directory of Open Access Journals (Sweden)

    Ranalli, A.

    1992-02-01

    Full Text Available Experiments of the biological treatment of the oil mill waste waters, deriving from continuous system, have been carried out with selected mutant ferments, adapted to rather forced toxic conditions. The commercial microbio formulations SNKD, LLMO and PSBIO have been utilized; the last two are liquid suspensions, constituted by living micro-organisms that, in contrast to those frozen or lyophilized, do not need be revitalized before their use and became completely active in short time. The experiments with the SNKD biological preparation were carried out both on filtered oil mill outflows (type A with an initial COD of approximately 43 g/l and on waste water dephenolized by Caro-acid (type B with a COD equal to 30 g/l. The experiments with LLMO and PSBIO complexes were conduced both on oil mill outflows filtered and diluted (ratio 1:0.5 with an initial COD equal to 44 g/l (type C, and on waste water that were filtered and preventatively subjected to a cryogenic treatment (type D, with an initial COD of approximately 22 g/l. The residual COD with the microbio formulation SNKD, was about 15 g/l (type A and 5 g/l (type B; with the PSBIO It was about 7 g/l (type C and 1.5 g/l (type D; with the microbio formulation LLMO it resulted in 6 g/l (type C and 1.3 g/l (type D.

    Han sido efectuadas pruebas de tratamiento biológico de alpechines, provenientes de sistemas continuos, con fermentos seleccionados adaptados a condiciones de toxicidad muy elevadas. Han sido utilizadas las formulaciones microbianas SNKD, LLMO y PSBIO; las dos últimas son suspensiones líquidas, constituidas por microorganismos vivos, los cuales a diferencia de los liofilizados o congelados, no deben ser revitalizados antes del uso; estos tienen una fase «lag» más breve y entran antes en completa actividad. Las pruebas con la preparación biológica SNKD han sido efectuadas en los alpechines filtrados (tipo A con DQO inicial alrededor de 43 g/l, y también con alpech

  12. Improved Energy Recovery by Anaerobic Grey Water Sludge Treatment with Black Water

    NARCIS (Netherlands)

    Tervahauta, T.H.; Bryant, I.M.; Hernandez Leal, L.; Buisman, C.J.N.; Zeeman, G.

    2014-01-01

    This study presents the potential of combining anaerobic grey water sludge treatment with black water in an up-flow anaerobic sludge blanket (UASB) reactor to improve energy recovery within source-separated sanitation concepts. Black water and the mixture of black water and grey water sludge were

  13. Riverbank filtration: an efficient and economical water treatment technology

    OpenAIRE

    Jaramillo uribe, Marcela

    2012-01-01

    Riverbank Filtration (RBF) is a water treatment technology that consists of extracting water from rivers by pumping wells located in the adjacent alluvial aquifer. During the underground passage, a series of physical, chemical, and biological processes take place, improving the quality of the surface water, substituting or reducing conventional drinking water treatment. Despite its extensive use in Europe and its emerging use in the United States, there are no scientific publications related ...

  14. Applications of nanotechnology in water and wastewater treatment.

    Science.gov (United States)

    Qu, Xiaolei; Alvarez, Pedro J J; Li, Qilin

    2013-08-01

    Providing clean and affordable water to meet human needs is a grand challenge of the 21st century. Worldwide, water supply struggles to keep up with the fast growing demand, which is exacerbated by population growth, global climate change, and water quality deterioration. The need for technological innovation to enable integrated water management cannot be overstated. Nanotechnology holds great potential in advancing water and wastewater treatment to improve treatment efficiency as well as to augment water supply through safe use of unconventional water sources. Here we review recent development in nanotechnology for water and wastewater treatment. The discussion covers candidate nanomaterials, properties and mechanisms that enable the applications, advantages and limitations as compared to existing processes, and barriers and research needs for commercialization. By tracing these technological advances to the physicochemical properties of nanomaterials, the present review outlines the opportunities and limitations to further capitalize on these unique properties for sustainable water management. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Drinking water safely during cancer treatment

    Science.gov (United States)

    ... from. This includes water for drinking, cooking, and brushing your teeth. Ask your health care provider about special care ... drink it or use it for cooking or brushing your teeth. Running well water through a filter or adding ...

  16. Peracids in water treatment:a critical review

    OpenAIRE

    Luukkonen, T. (Tero); Pehkonen, S. O. (Simo O.)

    2017-01-01

    Abstract Peracids have gained interest in the water treatment over the last few decades. Peracetic acid (CH₃CO₃H) has already become an accepted alternative disinfectant in wastewater disinfection whereas performic acid (CHO₃H) has been studied much less, although it is also already commercially available. Additionally, peracids have been studied for drinking water disinfection, oxidation of aqueous (micro)pollutants, sludge treatment, and ballast water treatment, to name just a few exampl...

  17. Innovations in nanotechnology for water treatment

    OpenAIRE

    Gehrke, Ilka; Geiser,Andreas; Somborn-Schulz,Annette

    2015-01-01

    Ilka Gehrke, Andreas Geiser, Annette Somborn-SchulzFraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT, Oberhausen, GermanyAbstract: Important challenges in the global water situation, mainly resulting from worldwide population growth and climate change, require novel innovative water technologies in order to ensure a supply of drinking water and reduce global water pollution. Against this background, the adaptation of highly advanced nanotechnology to traditional pro...

  18. K West integrated water treatment system subproject safety analysis document

    Energy Technology Data Exchange (ETDEWEB)

    SEMMENS, L.S.

    1999-02-24

    This Accident Analysis evaluates unmitigated accident scenarios, and identifies Safety Significant and Safety Class structures, systems, and components for the K West Integrated Water Treatment System.

  19. An efficient removal of crystal violet dye from waste water by adsorption onto TLAC/Chitosan composite: A novel low cost adsorbent.

    Science.gov (United States)

    Jayasantha Kumari, H; Krishnamoorthy, P; Arumugam, T K; Radhakrishnan, S; Vasudevan, D

    2017-03-01

    A composite of Typha latifolia activated carbon (TLAC) (a novel, low cost absorbent) and chitosan (TLAC/Chitosan composite) was prepared. The composite was characterised using IR spectra, XRD, FESEM and Pore size studies. Its effectivity was tested for the removal of crystal violet dye from aqueous solutions. The effect of pH, dose rate and initial dye concentration was evaluated. The adsorption isotherm, kinetics and thermodynamic parameters were studied. Langmuir and Freundlich isotherm models were found fit effectively for the dye adsorption data in the present study. The adsorption followed pseudo-second order kinetics. The evaluated thermodynamic parameters show a spontaneous and exothermic reaction. Overall, this study indicates TLAC/Chitosan composite as an effective adsorbent for the removal of crystal violet dye from aqueous solutions. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. DESALINATION AND WATER TREATMENT RESEARCH AT SANDIA NATIONAL LABORATORIES.

    Energy Technology Data Exchange (ETDEWEB)

    Rigali, Mark J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Miller, James E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Altman, Susan J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Biedermann, Laura [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Brady, Patrick Vane. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kuzio, Stephanie P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nenoff, Tina M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rempe, Susan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-11-01

    Water is the backbone of our economy - safe and adequate supplies of water are vital for agriculture, industry, recreation, and human consumption. While our supply of water today is largely safe and adequate, we as a nation face increasing water supply challenges in the form of extended droughts, demand growth due to population increase, more stringent health-based regulation, and competing demands from a variety of users. To meet these challenges in the coming decades, water treatment technologies, including desalination, will contribute substantially to ensuring a safe, sustainable, affordable, and adequate water supply for the United States. This overview documents Sandia National Laboratories' (SNL, or Sandia) Water Treatment Program which focused on the development and demonstration of advanced water purification technologies as part of the larger Sandia Water Initiative. Projects under the Water Treatment Program include: (1) the development of desalination research roadmaps (2) our efforts to accelerate the commercialization of new desalination and water treatment technologies (known as the 'Jump-Start Program),' (3) long range (high risk, early stage) desalination research (known as the 'Long Range Research Program'), (4) treatment research projects under the Joint Water Reuse & Desalination Task Force, (5) the Arsenic Water Technology Partnership Program, (6) water treatment projects funded under the New Mexico Small Business Administration, (7) water treatment projects for the National Energy Technology Laboratory (NETL) and the National Renewable Energy Laboratory (NREL), (8) Sandia- developed contaminant-selective treatment technologies, and finally (9) current Laboratory Directed Research and Development (LDRD) funded desalination projects.

  1. NPDES Permit for Crow Nation Water Treatment Plants in Montana

    Science.gov (United States)

    Under NPDES permit MT-0030538, the U.S. Bureau of Indian Affairs is authorized to discharge from the Crow Agency water treatment plants via the wastewater treatment facility located in Bighorn County, Montana to the Little Bighorn River.

  2. Radium and Other Radiological Chemicals: Drinking Water Treatment Strategies

    Science.gov (United States)

    Radium and Other Radiological Chemicals: Drinking Water Treatment Technologies Topics include: Introduction to Rad Chemistry, Summary of the Rad, Regulations Treatment Technology, and Disposal. The introductions cover atoms, ions, radium and uranium and the removal of radioac...

  3. Biological Treatment of Drinking Water: Applications, Advantages and Disadvantages

    Science.gov (United States)

    The fundamentals of biological treatment are presented to an audience of state drinking water regulators. The presentation covers definitions, applications, the basics of bacterial metabolism, a discussion of treatment options, and the impact that implementation of these options...

  4. A review on modification methods to cellulose-based adsorbents to improve adsorption capacity.

    Science.gov (United States)

    Hokkanen, Sanna; Bhatnagar, Amit; Sillanpää, Mika

    2016-03-15

    In recent decades, increased domestic, agricultural and industrial activities worldwide have led to the release of various pollutants, such as toxic heavy metals, inorganic anions, organics, micropollutants and nutrients into the aquatic environment. The removal of these wide varieties of pollutants for better quality of water for various activities is an emerging issue and a robust and eco-friendly treatment technology is needed for the purpose. It is well known that cellulosic materials can be obtained from various natural sources and can be employed as cheap adsorbents. Their adsorption capacities for heavy metal ions and other aquatic pollutants can be significantly affected upon chemical treatment. In general, chemically modified cellulose exhibits higher adsorption capacities for various aquatic pollutants than their unmodified forms. Numerous chemicals have been used for cellulose modifications which include mineral and organic acids, bases, oxidizing agent, organic compounds, etc. This paper reviews the current state of research on the use of cellulose, a naturally occurring material, its modified forms and their efficacy as adsorbents for the removal of various pollutants from waste streams. In this review, an extensive list of various cellulose-based adsorbents from literature has been compiled and their adsorption capacities under various conditions for the removal of various pollutants, as available in the literature, are presented along with highlighting and discussing the key advancement on the preparation of cellulose-based adsorbents. It is evident from the literature survey presented herein that modified cellulose-based adsorbents exhibit good potential for the removal of various aquatic pollutants. However, still there is a need to find out the practical utility of these adsorbents on a commercial scale, leading to the improvement of pollution control. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Water Footprint Assessment in Waste Water Treatment Plant: Indicator of the sustainability of urban water cycle.

    Science.gov (United States)

    Gómez Llanos, Eva; Durán Barroso, Pablo; Matías Sánchez, Agustín; Fernández Rodríguez, Santiago; Guzmán Caballero, Raúl

    2017-04-01

    The seventeen Sustainable Development Goals (SDG) represent a challenge for citizens and countries around the world by working together to reduce social inequality, to fight poverty and climate change. The Goal six water and sanitation aims for ensuring, among others, the protection and restoration of water-related ecosystem (target 6.6) and encouraging the water use efficiency (target 6.3). The commitment to this goal is not only the development of sanitation infrastructure, but also incorporates the necessity of a sustainable and efficient management from ecological and economic perspectives. Following this approach, we propose a framework for assessing the waste water treatment plant (WWTP) management based on the Water Footprint (WF) principles. The WF as indicator is able to highlight the beneficial role of WWTPs within the environment and provide a complementary information to evaluate the impact of a WWTP regarding to the use of freshwater and energy. Therefore, the footprint family provides an opportunity to relate the reduction of pollutant load in a WWTP and the associated consumptions in terms of electricity and chemical products. As a consequence, the new methodology allows a better understanding of the interactions among water and energy resources, economic requirements and environmental risks. Because of this, the current technologies can be improved and innovative solutions for monitoring and management of urban water use can be integrated. The WF was calculated in four different WWTP located in the North East of Extremadura (SW Spain) which have activated sludge process as secondary treatment. This zone is characterized by low population density but an incipient tourism development. The WF estimation and its relationship with the electricity consumption examines the efficiency of each WWTP and identifies the weak points in the management in terms of the sustainability. Consequently, the WF establishes a benchmark for multidisciplinary decision

  6. Treatment of dairy wastewater by water hyacinth.

    Science.gov (United States)

    Munavalli, G R; Saler, P S

    2009-01-01

    The present study addresses potential of water hyacinth for treating small-scale dairy wastewater to satisfy effluent standards for disposal into public sewers. The batch experiments were conducted on dairy wastewater using reactor with water hyacinth and without water hyacinth. The Chemical Oxygen Demand (COD) was varied from 507 mg/L to 4,672 mg/L and the maximum Hydraulic Retention Time (HRT) adopted was 8 days. The loss of water due to evapo-transpiration and evaporation was also measured. The water hyacinth system performed better when initial COD concentration was maintained less than 1,672 mg/L for six days HRT. The performance of water hyacinth system was more effective than reference by 30% to 45% for COD removal. However, water hyacinth had no significant impact in reducing Total Dissolved Solids (TDS). The evapo-transpiration loss was almost double than the evaporation loss. The first order reaction kinetics was applicable and reaction rate parameters were estimated for various organic strengths of wastewater. The reaction rate parameters for water hyacinth system were three times higher than a system without water hyacinth and also found to vary with initial COD values. Water hyacinth can be adopted to treat dairy wastewater from small-scale dairy effectively for disposal into public sewers.

  7. Iodine and fluorine removal of the water using two synthetic adsorbents of great fixation capacity; Remocion de iodo y fluor del agua utilizando dos adsorbentes sinteticos de gran capacidad de fijacion

    Energy Technology Data Exchange (ETDEWEB)

    Neri G, M. [Instituto Tecnologico de Toluca, Av. Tecnologico s/n, Ex-Rancho La Virgen, Metepec, Estado de Mexico (Mexico); Badillo A, V. E., E-mail: martinee_@live.com.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2012-10-15

    In this work is studied the affinity of two synthetic adsorbents of great fixation capacity, the alumina and the hydroxyapatite, as alternative for the removal of two halogens, iodine and fluorine of the water; the first of importance in the radioactive wastes management and the second of interest in public health. This study was carried out applying the technique of radioactive tracers, with {sup 131}I and the radionuclide {sup 18}F (it produced in the unit PET-cyclotron of the UNAM). The affinity of the synthetic adsorbents for the halogens is expressed in terms of the distribution coefficient and of the retention percent in function of the solution ph. The results obtained for the iodine and fluorine in the synthetic solids are markedly different; in the case of the iodine, the retention is worthless in the whole interval of studied ph while for the fluorine high distribution coefficient and fixation percentages are presented of until 100%. Also for the fluorine in hydroxyapatite high distribution coefficients and superiors are obtained in relation to those that are obtained in the alumina. In both solids the fluorine retention diminishes as the ph of the solution increases, what shows the competition with the hydroxyl ions for the active places in surface. (Author)

  8. High performance Mo adsorbent PZC

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1998-10-01

    We have developed Mo adsorbents for natural Mo(n, {gamma}){sup 99}Mo-{sup 99m}Tc generator. Among them, we called the highest performance adsorbent PZC that could adsorb about 250 mg-Mo/g. In this report, we will show the structure, adsorption mechanism of Mo, and the other useful properties of PZC when you carry out the examination of Mo adsorption and elution of {sup 99m}Tc. (author)

  9. Drinking water contamination and treatment techniques

    Science.gov (United States)

    Sharma, S.; Bhattacharya, A.

    2017-06-01

    Water is of fundamental importance for life on earth. The synthesis and structure of cell constituents and transport of nutrients into the cells as well as body metabolism depend on water. The contaminations present in water disturb the spontaneity of the mechanism and result in long/short-term diseases. The probable contaminations and their possible routes are discussed in the present review. Continued research efforts result in some processes/technologies to remove the contaminations from water. The review includes concepts and potentialities of the technologies in a comprehensible form. It also includes some meaningful hybrid technologies and promising awaited technologies in coming years.

  10. Computational fluid dynamic analysis for independent floating water treatment device

    Science.gov (United States)

    Zawawi, M. H.; Swee, M. G.; Zainal, N. S.; Zahari, N. M.; Kamarudin, M. A.; Ramli, M. Z.

    2017-09-01

    This project is to design and develop 3D Independent Floating Water Treatment Device using 3D CAD software. The device is designed to treat water for better water qualities and water flows of the lakes. A prototype was manufactured to study the water treatment efficiency of the device. Computational Fluid Dynamic (CFD) analysis was used to capture the efficiency of the Independent Floating Water Treatment Device by simulates and model the water flows, pressure and velocity. According to the results, the maximum velocity magnitude was around 1m3/s. The velocity contour showed the device has high velocity at the pipe outlet. The velocity became lower and lower as the distance is further from the pipe outlet. The result from the velocity measurement was 1.05m/s. The pressure magnitude was in between 1426 Pa to 1429 Pa. The laboratory results based on water parameters proved that the water movement and direction of water flow of the Independent Floating Water Treatment Device enable the efficient pollutant removal. The vector plot, velocity contour, water flow path lines, water flow streamline and pressure contour was successful modeled.

  11. The function of advanced treatment process in a drinking water treatment plant with organic matter-polluted source water.

    Science.gov (United States)

    Lin, Huirong; Zhang, Shuting; Zhang, Shenghua; Lin, Wenfang; Yu, Xin

    2017-04-01

    To understand the relationship between chemical and microbial treatment at each treatment step, as well as the relationship between microbial community structure in biofilms in biofilters and their ecological functions, a drinking water plant with severe organic matter-polluted source water was investigated. The bacterial community dynamics of two drinking water supply systems (traditional and advanced treatment processes) in this plant were studied from the source to the product water. Analysis by 454 pyrosequencing was conducted to characterize the bacterial diversity in each step of the treatment processes. The bacterial communities in these two treatment processes were highly diverse. Proteobacteria, which mainly consisted of beta-proteobacteria, was the dominant phylum. The two treatment processes used in the plant could effectively remove organic pollutants and microbial polution, especially the advanced treatment process. Significant differences in the detection of the major groups were observed in the product water samples in the treatment processes. The treatment processes, particularly the biological pretreatment and O 3 -biological activated carbon in the advanced treatment process, highly influenced the microbial community composition and the water quality. Some opportunistic pathogens were found in the water. Nitrogen-relative microorganisms found in the biofilm of filters may perform an important function on the microbial community composition and water quality improvement.

  12. 77 FR 12227 - Long Term 2 Enhanced Surface Water Treatment Rule: Uncovered Finished Water Reservoirs; Public...

    Science.gov (United States)

    2012-02-29

    ... AGENCY 40 CFR Parts 141 and 142 Long Term 2 Enhanced Surface Water Treatment Rule: Uncovered Finished Water Reservoirs; Public Meeting AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of public... requirement in the Long Term 2 Enhanced Surface Water Treatment Rule (LT2 rule). At this meeting, EPA will...

  13. A novel, integrated treatment system for coal waste waters. Quarterly report, June 2, 1993--September 1, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H.Y.; Srinivasan, K.R.

    1993-12-31

    The aims of this study are to develop, characterize and optimize a novel treatment scheme that would be effective simultaneously against the toxic organics and the heavy metals present in coal conversion waste waters. In this report, the following findings have been reported and discussed. Acid-base titration of Duomeen-T (DT), a diamine surfactant, that has been used in this study to modify smectite surfaces to form smectite-DT complexes has been undertaken. In aqueous medium containing 5% by volume iso propyl alcohol (IPA), DT shows a broad distribution of pKa with a mean value of 7.55. This finding suggests that DT is a much weaker base than a typical diamine and helps explain the fact that Cu(II) adsorbs specifically onto DT with maximal affinity in the pH range 7.2--7.5. Electrokinetic sonic amplitude (ESA) measurements on DT-smectite complexes also reveal that the mean pKa of the adsorbed DT is around 7.0. This finding supports our earlier observations that Cu(II) and Cd(II) cations bind strongly through specific interaction to DT-smectite surface in the pH range 7.0--8.0. Our results also show that DT is fully protonated at pH 4.5, and it is at this pH that Cr(VI) is maximally adsorbed as counterions to the DT-smectite surface. These and our earlier results provide a firm basis to conclude that a heterogeneous mixture of diamine surfactants can be used to adsorb and desorb cationic and anionic heavy metals from their respective aqueous solutions as a function of the solution pH.

  14. Industrial water pollution, water environment treatment, and health risks in China.

    Science.gov (United States)

    Wang, Qing; Yang, Zhiming

    2016-11-01

    The negative health effects of water pollution remain a major source of morbidity and mortality in China. The Chinese government is making great efforts to strengthen water environment treatment; however, no studies have evaluated the effects of water treatment on human health by water pollution in China. This study evaluated the association between water pollution and health outcomes, and determined the extent to which environmental regulations on water pollution may lead to health benefits. Data were extracted from the 2011 and 2013 China Health and Retirement Longitudinal Study (CHARLS). Random effects model and random effects Logit model were applied to study the relationship between health and water pollution, while a Mediator model was used to estimate the effects of environmental water treatment on health outcomes by the intensity of water pollution. Unsurprisingly, water pollution was negatively associated with health outcomes, and the common pollutants in industrial wastewater had differential impacts on health outcomes. The effects were stronger for low-income respondents. Water environment treatment led to improved health outcomes among Chinese people. Reduced water pollution mediated the associations between water environment treatment and health outcomes. The results of this study offer compelling evidence to support treatment of water pollution in China. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. 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

    Directory of Open Access Journals (Sweden)

    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

  16. Improved Energy Recovery by Anaerobic Grey Water Sludge Treatment with Black Water

    Directory of Open Access Journals (Sweden)

    Taina Tervahauta

    2014-08-01

    Full Text Available This study presents the potential of combining anaerobic grey water sludge treatment with black water in an up-flow anaerobic sludge blanket (UASB reactor to improve energy recovery within source-separated sanitation concepts. Black water and the mixture of black water and grey water sludge were compared in terms of biochemical methane potential (BMP, UASB reactor performance, chemical oxygen demand (COD mass balance and methanization. Grey water sludge treatment with black water increased the energy recovery by 23% in the UASB reactor compared to black water treatment. The increase in the energy recovery can cover the increased heat demand of the UASB reactor and the electricity demand of the grey water bioflocculation system with a surplus of 0.7 kWh/cap/y electricity and 14 MJ/cap/y heat. However, grey water sludge introduced more heavy metals in the excess sludge of the UASB reactor and might therefore hinder its soil application.

  17. Survey of disinfection efficiency of small drinking water treatment ...

    African Journals Online (AJOL)

    A survey involving 181 water treatment plants across 7 provinces of South Africa: Mpumalanga, Limpopo, North West, Free State, KwaZulu-Natal, Eastern Cape and Western Cape was undertaken to identify the challenges facing small water treatment plants (SWTPs) in South Africa . Information gathered included ...

  18. Gamma radiation treatment of waste waters from textile industries in ...

    African Journals Online (AJOL)

    Effects of gamma irradiation alone, and in combination with chemical treatment on color, odor, chemical oxyg-en demand (COD) and suspended solids in waste waters from textile industries in Ghana were studied to explore the potential of alternative and innovative processes for treatment of industrial waste waters. Waste ...

  19. Life cycle assessment of advanced waste water treatment

    DEFF Research Database (Denmark)

    Larsen, Henrik Fred; Hansen, Peter Augusto

    The EU FP6 NEPTUNE project is related to the EU Water Framework Directive and the main goal is to develop new and optimize existing waste water treatment technologies (WWTT) and sludge handling methods for municipal waste water. Besides nutrients, a special focus area is micropollutants (e....... In total more that 20 different waste water and sludge treatment technologies are to be assessed. This paper will present the preliminary LCA results from running the induced versus avoided impact approach (mainly based on existing LCIA methodology) on one of the advanced treatment technologies, i...

  20. Nanofiltration for water and wastewater treatment – a mini review

    Directory of Open Access Journals (Sweden)

    H. K. Shon

    2013-06-01

    Full Text Available The application of membrane technology in water and wastewater treatment is increasing due to stringent water quality standards. Nanofiltration (NF is one of the widely used membrane processes for water and wastewater treatment in addition to other applications such as desalination. NF has replaced reverse osmosis (RO membranes in many applications due to lower energy consumption and higher flux rates. This paper briefly reviews the application of NF for water and wastewater treatment including fundamentals, mechanisms, fouling challenges and their controls.

  1. Discharge and Treatment of Waste Water in Denmark

    DEFF Research Database (Denmark)

    Larsen, Torben

    1990-01-01

    This paper describes the waste water treatment situation in the area of Esbjerg. This example was chosen because the situation in Esbjerg is typical of that of most towns in Denmark, and because Esbjerg is closest to the British situation with respect to the receiving water. Esbjerg has...... a population of 70.000 inhabitans, and waste water treatment takes place in two treatment plants. These plants are now being extended to perform tertiary treatment, to fulfil the new Danish requirements. From 1992, the maximum average concentrations allowed for municipal waste water discharges to receiving...... waters will be; 15 mg/1 for BOD5, 8 mg/1 for total nitrogen, and 1.5 mg/1 for total phosphorus. These general requirements cover all types of receiving waters, but regional authorities have, in a number of cases, fixed lower values for sensitive areas....

  2. Introducing Water-Treatment Subjects into Chemical Engineering Education.

    Science.gov (United States)

    Caceres, L.; And Others

    1992-01-01

    Proposes that inclusion of waste water treatment subjects within the chemical engineering curriculum can provide students with direct access to environmental issues from both a biotechnological and an ethical perspective. The descriptive details of water recycling at a copper plant and waste water stabilization ponds exemplify this approach from…

  3. Hot water treatments delay cold-induced banana peel blackening

    NARCIS (Netherlands)

    Promyou, S.; Ketsa, S.; Doorn, van W.G.

    2008-01-01

    Banana fruit of cv. Gros Michel (Musa acuminata, AAA Group, locally called cv. Hom Thong) and cv. Namwa (Musa x paradisiaca, ABB Group) were immersed for 5, 10 and 15 min in water at 42 degrees C, or in water at 25 degrees C (control), and were then stored at 4 degrees C. Hot water treatment for 15

  4. Characterisation of some South African water treatment residues ...

    African Journals Online (AJOL)

    Land application of water treatment residue (WTR) the by-product from the production ... density and plant available water) and chemical attributes (pH, electrical conductivity, ... a wide range in particle size distribution as well as plant available water. ... especially in the Faure WTRs, which may lead to plant growth problems.

  5. Biological treatment of drinking water by chitosan based ...

    African Journals Online (AJOL)

    ABI

    2015-03-18

    Mar 18, 2015 ... A membrane filtration technique is used for the treatment of water to remove or kill the bacteria from drinking water sample. ... improved with a variety of reactor groups to raise their affinity to target compounds for removal of organic and inorganic ... sponges or outside coating of water storage tanks. It has.

  6. Modelling of a Small Scale Waste Water Treatment Plant (SSWWTP)

    African Journals Online (AJOL)

    PROF. OLIVER OSUAGWA

    2014-06-01

    Jun 1, 2014 ... source of energy. Future effort will be focus on improving the efficiency of energy used in the waste water [3]. Aim. The aim of this project is to bring into existence a Small Scale Waste Water. Treatment Plant that can convert a waste water with high Chemical Oxygen Demand (COD) and high Biological ...

  7. Household water treatment and safe storage-effectiveness and economics

    NARCIS (Netherlands)

    Stubbé, Stefanie M L; Pelgrim-Adams, Alida; Szántó, Gabor L.; van Halem, D.

    2016-01-01

    Household Water Treatment and safe Storage (HWTS) systems aim to provide safe drinking water in an affordable manner to users where safe piped water supply is either not feasible or not reliable. In this study the effectiveness, economic parameters and costs of three selected HWTS systems were

  8. Effect of polyaluminium chloride water treatment sludge on effluent ...

    African Journals Online (AJOL)

    Water resources degeneration is accelerated by the discharge of untreated wastewater and its byproducts, hence, reuse of these wastes is a major contributor to sustaining fresh water for the coming decades. In this study, the reuse of polyaluminium water treatment sludge (PA-WTS) as a flocculant aid to improve the ...

  9. Toxic cyanobacteria and drinking water: Impacts, detection, and treatment.

    Science.gov (United States)

    He, Xuexiang; Liu, Yen-Ling; Conklin, Amanda; Westrick, Judy; Weavers, Linda K; Dionysiou, Dionysios D; Lenhart, John J; Mouser, Paula J; Szlag, David; Walker, Harold W

    2016-04-01

    Blooms of toxic cyanobacteria in water supply systems are a global issue affecting water supplies on every major continent except Antarctica. The occurrence of toxic cyanobacteria in freshwater is increasing in both frequency and distribution. The protection of water supplies has therefore become increasingly more challenging. To reduce the risk from toxic cyanobacterial blooms in drinking water, a multi-barrier approach is needed, consisting of prevention, source control, treatment optimization, and monitoring. In this paper, current research on some of the critical elements of this multi-barrier approach are reviewed and synthesized, with an emphasis on the effectiveness of water treatment technologies for removing cyanobacteria and related toxic compounds. This paper synthesizes and updates a number of previous review articles on various aspects of this multi-barrier approach in order to provide a holistic resource for researchers, water managers and engineers, as well as water treatment plant operators. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. The reactive surface of Castor leaf [Ricinus communis L.] powder as a green adsorbent for the removal of heavy metals from natural river water

    Science.gov (United States)

    Martins, Amanda E.; Pereira, Milene S.; Jorgetto, Alexandre O.; Martines, Marco A. U.; Silva, Rafael I. V.; Saeki, Margarida J.; Castro, Gustavo R.

    2013-07-01

    In this study, a green adsorbent was successfully applied to remove toxic metals from aqueous solutions. Dried minced castor leaves were fractionated into 63-μm particles to perform characterization and extraction experiments. Absorption bands in FTIR (Fourier Transform Infrared Spectroscopy) spectra at 1544, 1232 and 1350 cm-1 were assigned to nitrogen-containing groups. Elemental analysis showed high nitrogen and sulfur content: 5.76 and 1.93%, respectively. The adsorption kinetics for Cd(II) and Pb(II) followed a pseudo-second-order model, and no difference between the experimental and calculated Nf values (0.094 and 0.05 mmol g-1 for Cd(II) and Pb(II), respectively) was observed. The Ns values calculated using the modified Langmuir equation, 0.340 and 0.327 mmol g-1 for Cd(II) and Pb(II), respectively, were superior to the results obtained for several materials in the literature. The method proposed in this study was applied to pre-concentrate (45-fold enrichment factor) and used to measure Cd(II) and Pb(II) in freshwater samples from the Paraná River. The method was validated through a comparative analysis with a standard reference material (1643e).

  11. Magnetic adsorbent constructed from the loading of amino functionalized Fe{sub 3}O{sub 4} on coordination complex modified polyoxometalates nanoparticle and its tetracycline adsorption removal property study

    Energy Technology Data Exchange (ETDEWEB)

    Ou, Jinzhao; Mei, Mingliang; Xu, Xinxin, E-mail: xuxx@mail.neu.edu.cn

    2016-06-15

    A magnetic polyoxometalates based adsorbent has been synthesized successfully through the loading of amino functionalized Fe{sub 3}O{sub 4} (NH{sub 2}-Fe{sub 3}O{sub 4}) on nanoparticle of a coordination complex modified polyoxometalates (CC/POMNP). FTIR illustrate there exist intense hydrogen bonds between NH{sub 2}-Fe{sub 3}O{sub 4} and CC/POMNP, which keep the stability of this adsorbent. At room temperature, this adsorbent exhibits ferromagnetic character with saturation magnetization of 8.19 emu g{sup −1}, which provides prerequisite for fast magnetic separation. Water treatment experiment illustrates this POM based magnetic adsorbent exhibits high adsorption capacity on tetracycline. The adsorption process can be described well with Temkin model, which illustrates the interaction between adsorbent and tetracycline plays the dominated role in tetracycline removal. The rapid, high efficient tetracycline adsorption ability suggests this POM based magnetic adsorbent exhibits promising prospect in medical and agriculture waste water purification. A magnetic polyoxometalates based adsorbent, which exhibits excellent tetracycline adsorption removal property has been synthesized through the loading of NH{sub 2}-Fe{sub 3}O{sub 4} on coordination complex modified polyoxometalates - Graphical abstract: A magnetic polyoxometalates based adsorbent, which exhibits excellent tetracycline adsorption removal property has been synthesized through the loading of NH{sub 2}-Fe{sub 3}O{sub 4} on coordination complex modified polyoxometalate. Display Omitted - Highlights: • A POM based magnetic adsorbent was fabricated through the loading of NH{sub 2}-Fe{sub 3}O{sub 4} on POM nanoparticle. • This adsorbent possesses excellent tetracycline adsorption property. • Saturation magnetization value of this adsorbent is 8.19 emug−1, which is enough for magnetic separation.

  12. Comparison study of phosphorus adsorption on different waste solids: Fly ash, red mud and ferric-alum water treatment residues.

    Science.gov (United States)

    Wang, Ying; Yu, Yange; Li, Haiyan; Shen, Chanchan

    2016-12-01

    The adsorption of phosphorus (P) onto three industrial solid wastes (fly ash, red mud and ferric-alum water treatment residual (FAR)) and their modified materials was studied systematically via batch experiments. Compared with two natural adsorbents (zeolite and diatomite), three solid wastes possessed a higher adsorption capacity for P because of the higher Fe, Al and Ca contents. After modification (i.e., the fly ash and red mud modified by FeCl 3 and FARs modified by HCl), the adsorption capacity increased, especially for the modified red mud, where more Fe bonded P was observed. The P adsorption kinetics can be satisfactorily fitted using the pseudo-second-order model. The Langmuir model can describe well the P adsorption on all of the samples in our study. pH and dissolved organic matter (DOM) are two important factors for P adsorption. Under neutral conditions, the maximum adsorption amount on the modified materials was observed. With the deviation from pH7, the adsorption amount decreased, which resulted from the change of P species in water and surface charges of the adsorbents. The DOM in water can promote P adsorption, which may be due to the promotion effects of humic-Fe(Al) complexes and the pH buffer function exceeds the depression of competitive adsorption. Copyright © 2016. Published by Elsevier B.V.

  13. The Use Combined Adsorbant to Extend the Storing Period of Cavendish Banana

    Directory of Open Access Journals (Sweden)

    Suryatmi Retno Dumadi

    2001-04-01

    Full Text Available Post harvest damage of horticulture commodity in Indonesia has reached 30 to 40%. This research is aimed at extending the storing period of cavendish banana in order to extend the market range, while still enabling to maintain the quality of fresh preserved banana as required by consumers. One of the ways to do so is by using combines adsorbant as to control the air of the fruit surrounding.The type of adsorbant used is as follows : 1,2 and 3% of KMn04 ; 0,5, 1 and 1,5% of iron powder, and 3% of active carbon. The experiment was conducted in completed randomized design, by 10 factors of combined and concentrate adsorbant, and by 6 factors of storing time. The parameters being analyzed includes texture intensity, starch rate, total acid rate, total glucose rate, water rate and reduced glucose rate.The statistics test results of 10 treatments of combines adsorbant KMn04, iron powder, active carbon which were(1%, 0,5%, 3%, (1%, 1%, 3%, (1%, 1,5%,3%, (2%, 0,5%, 3%, (2%, 1%, 3%, (2%, 1.5%, 3% (3%, 0,5%, 3%, (3%, 1%, 3% ( 3%, 1,5%, 3%, suggested that the combined adsorbant (2%, 1,5%, 3% at 15°C storing temperature is the best. This treatment is the best because it has the highest substances rate up to 72.36% db; relatively small texture change, total acid rate, total glucose rate, water rate and the lowest reduced glucose rate of 3.531% db which is more likely to extend the storing period of cavendish banana for approximately six weeks.

  14. Integrated water quality, emergy and economic evaluation of three bioremediation treatment systems for eutrophic water

    Science.gov (United States)

    This study was targeted at finding one or more environmentally efficient, economically feasible and ecologically sustainable bioremediation treatment modes for eutrophic water. Three biological species, i.e. water spinach (Ipomoea aquatica), loach (Misgurus anguillicaudatus) and ...

  15. Water Treatment Systems Make a Big Splash

    Science.gov (United States)

    2004-01-01

    In the 1960s, NASA's Manned Space Center (now known as Johnson Space Center) and the Garrett Corporation, Air Research Division, conducted a research program to develop a small, lightweight water purifier for the Apollo spacecraft that would require minimal power and would not need to be monitored around-the-clock by astronauts in orbit. The 9-ounce purifier, slightly larger than a cigarette pack and completely chlorine-free, dispensed silver ions into the spacecraft s water supply to successfully kill off bacteria. A NASA Technical Brief released around the time of the research reported that the silver ions did not impart an unpleasant taste to the water. NASA s ingenuity to control microbial contamination in space caught on quickly, opening the doors for safer methods of controlling water pollutants on Earth.

  16. MWH's water treatment: principles and design

    National Research Council Canada - National Science Library

    Crittenden, John C

    2012-01-01

    .... The contents have been updated to cover changes to regulatory requirements, testing methodology, and design approaches, as well as the emergent topics of pharmacological agents in the water supply...

  17. Disinfection of Water by Ultrasound: Application to Ballast Water Treatment

    National Research Council Canada - National Science Library

    Brizzolara, Robert A; Holm, Eric R; Stamper, David M

    2006-01-01

    .... A contact time for one log kill of an E. coli pure culture of 0.6 minutes was measured when using higher average intensities resulting from reduced treatment cell diameters, a substantial improvement over previous work...

  18. Sustainable conversion of agro-wastes into useful adsorbents

    Science.gov (United States)

    Bello, Olugbenga Solomon; Owojuyigbe, Emmanuel Seun; Babatunde, Monsurat Abiodun; Folaranmi, Folasayo Eunice

    2017-11-01

    Preparation and characterization of raw and activated carbon derived from three different selected agricultural wastes: kola nut pod raw and activated (KNPR and KNPA), bean husk raw and activated (BHR and BHA) and coconut husk raw and activated (CHR and CHA) were investigated, respectively. Influences of carbonization and acid activation on the activated carbon were investigated using SEM, FTIR, EDX, pHpzc and Boehm titration techniques, respectively. Carbonization was done at 350 °C for 2 h followed by activation with 0.3 M H3PO4 (ortho-phosphoric acid). Results obtained from SEM, FTIR, and EDX revealed that, carbonization followed by acid activation had a significant influence on morphology and elemental composition of the samples. SEM showed well-developed pores on the surface of the precursors after acid treatment, FTIR spectra revealed reduction, broadening, disappearance or appearance of new peaks after acid activation. EDX results showed highest percentage of carbon by atom respectively in the order BHA > KNPA > CHA respectively. The pHpzc was found to be 5.32, 4.57 and 3.69 for KNPA, BHA and CHA, respectively. Boehm titration result compliments that of pHpzc, indicating that the surfaces of the prepared adsorbents are predominantly acidic. This study promotes a sustainable innovative use of agro-wastes in the production of cheap and readily available activated carbons, thereby ensuring more affordable water and effluent treatment adsorbents.

  19. Experimental design to optimize preparation of activated carbons for use in water treatment.

    Science.gov (United States)

    Baçaoui, Abdelaziz; Dahbi, Abderrahman; Yaacoubi, Abdelrani; Bennouna, Chakib; Maldonado-Hódar, Francisco J; Rivera-Utrilla, José; Carrasco-Marín, Francisco; Moreno-Castilla, Carlos

    2002-09-01

    A series of seven activated carbons was obtained for use in drinking water treatments by steam-activation of olive-waste cakes. This raw material is an abundant and cheap waste byproduct of oil production, making these activated carbons economically feasible. The activated carbons, prepared by the one step method, were characterized, and the evolution of their characteristics (yield, adsorption capacities, and porosity) was analyzed as a function of the experimental parameters (activation temperature and activation time), using the Doehlert matrix. The Doehlert matrix allows the response surface to be studied with a good quality parameter estimation of the quadratic model. Each response has been described by a second order model that was adequate to predict responses in all experimental regions. The coefficients of the postulated model were calculated from the experimental responses by means of least squares regression, using the NEMROD software. We determined the region in which the optimum values of both activation temperature and activation time were achieved for the preparation of activated carbons suitable for use in water treatments. The "optimal activated carbon" was experimentally obtained, and its characteristic parameters showed a good agreement with those calculated from the model. The results obtained for activated carbons prepared by the one-step method were compared with those for activated carbons prepared by the two-step method. The characteristics of activated carbons obtained by the one-step and two-step methods showed that "one-step" activated carbons have a highly developed porous texture formed mainly of large macropores and micropores, whereas "two-step" activated carbons have a predominance of mesopores and narrow micropores. These activated carbons from olive-waste cakes showed a high capacity to adsorb herbicides (2,4-dichlorophenoxyacetic acid, 2,4-D; and 2-methyl, 4-chlorophenoxyacetic acid, MCPA) from water, with adsorption capacity

  20. Carbon nanotube-based benzyl polymethacrylate composite monolith as a solid phase extraction adsorbent and a stationary phase material for simultaneous extraction and analysis of polycyclic aromatic hydrocarbon in water.

    Science.gov (United States)

    Al-Rifai, Asma'a; Aqel, Ahmad; Wahibi, Lamya Al; ALOthman, Zeid A; Badjah-Hadj-Ahmed, Ahmed-Yacine

    2018-02-02

    A composite of multi-walled carbon nanotubes incorporated into a benzyl methacrylate-co-ethylene dimethacrylate porous monolith was prepared, characterized and used as solid phase adsorbent and as stationary phase for simultaneous extraction and separation of ten polycyclic aromatic hydrocarbons, followed by nano-liquid chromatography analysis. The extraction and chromatographic parameters were optimized with regard to the extraction efficiency and the quality of chromatographic analytes separation. Under the optimized conditions, all PAHs were separated in 13 min with suitable resolution values (Rs = 1.74-3.98). Addition of a small amount of carbon nanotubes (0.1% with respect to monomers) to the polymerization mixture increased the efficiency for the separation column to over 41,700 plates m-1 for chrysene at flow rate of 0.5 μL min-1. The method showed a wide linear range (1-500 μg L-1 with R2 more than 0.9938), acceptable extraction repeatability (RSDs extraction cartridges) and satisfactory detection limits (0.02-0.22 μg L-1). Finally, the proposed method was successfully applied to the detection of polycyclic aromatic hydrocarbons in environmental water samples. After a simple extraction procedure with preconcentration factor equal to 100, the average recovery values in ultra-pure, tap and sea water samples were found to be in the range 81.3-95.4% with %RSD less than 6.4. Again, the presence of carbon nanotubes (0.3% relatively to monomers) in native polymer enhanced the extraction performance for the solid phase adsorbent up to 78.4%. The application of the monoliths modified with CNTs in extraction and nano-scale liquid chromatography for analysis of environmental samples offered several advantages; it demonstrated an acceptable precision, low detection limits, good reproducibility, satisfying recoveries and wide dynamic linear ranges. Copyright © 2018. Published by Elsevier B.V.

  1. Region 9 NPDES Facilities - Waste Water Treatment Plants

    Science.gov (United States)

    Point geospatial dataset representing locations of NPDES Waste Water Treatment Plant Facilities. NPDES (National Pollution Discharge Elimination System) is an EPA permit program that regulates direct discharges from facilities that discharge treated waste water into waters of the US. Facilities are issued NPDES permits regulating their discharge as required by the Clean Water Act. A facility may have one or more outfalls (dischargers). The location represents the facility or operating plant.

  2. Region 9 NPDES Facilities 2012- Waste Water Treatment Plants

    Science.gov (United States)

    Point geospatial dataset representing locations of NPDES Waste Water Treatment Plant Facilities. NPDES (National Pollution Discharge Elimination System) is an EPA permit program that regulates direct discharges from facilities that discharge treated waste water into waters of the US. Facilities are issued NPDES permits regulating their discharge as required by the Clean Water Act. A facility may have one or more outfalls (dischargers). The location represents the facility or operating plant.

  3. Methods for waste waters treatment in textile industry

    OpenAIRE

    Srebrenkoska, Vineta; Zezova, Silvana; Spasova, Sanja; Golomeova, Saska

    2014-01-01

    The processes of production of textiles or wet treatments and finishing processes of textile materials are huge consumers of water with high quality. As a result of these various processes, considerable amounts of polluted water are released. This paper puts emphasis on the problem of environmental protection against waste waters generated by textile industry. The methods of pretreatment or purification of waste waters in the textile industry can be: Primary (screening, sedimentation, homo...

  4. Competitive Adsorption of Cadmium (II from Aqueous Solutions onto Nanoparticles of Water Treatment Residual

    Directory of Open Access Journals (Sweden)

    Elsayed Elkhatib

    2016-01-01

    Full Text Available There is increasing interest in using water treatment residuals (WTRs for heavy metals removal from wastewater due to their low cost, availability, and high efficiency in removing various pollutants. In this study, novel water treatment residuals nanoparticles (nWTRs were prepared using high energy ball milling and used for efficient removal of Cd(II in single- and multi-ion systems. The WTR nanoparticles demonstrated high removal efficiency for Cd from aqueous solution as the adsorption capacities of nWTR were 17 and 10 times higher than those of bulk WTR in single- and multielement systems, respectively. Noticeably, Cd(II adsorption was clearly suppressed in the multi-ion system as Cu and Pb form the most stable monohydroxo complexes. Fourier transmission infrared (FTIR analyses suggested the participation of OH−, O-Al-O, FeOH, and FeOOH entities in the adsorption process. The stability of Cd-nWTR surface complexes is evident as less than 0. 2% of adsorbed Cd(ll was released at the highest Cd(II concentration load after 4 consecutive desorption cycles. Moreover, the real efficiency of nWTR for Cd(II removal from wastewater samples studied was calculated to be 98.35%. These results highlight the potential of nWTR for heavy metals removal from wastewater.

  5. Membrane distillation for wastewater reverse osmosis concentrate treatment with water reuse potential

    KAUST Repository

    Naidu, Gayathri

    2016-11-29

    Membrane distillation (MD) was evaluated as a treatment option of wastewater reverse osmosis concentrate (WWROC) discharged from wastewater reclamation plants (WRPs). A direct contact MD (DCMD), at obtaining 85% water recovery of WWROC showed only 13–15% flux decline and produced good quality permeate (10–15 µS/cm, 99% ion rejection) at moderate feed temperature of 55 °C. Prevalent calcium carbonate (CaCO3) deposition on the MD membrane occurred in treating WWROC at elevated concentrations. The combination of low salinity and loose CaCO3 adhesion on the membrane did not significantly contribute to DCMD flux decline. Meanwhile, high organic content in WWROC (58–60 mg/L) resulted in a significant membrane hydrophobicity reduction (70% lower water contact angle than virgin membrane) attributed to low molecular weight organic adhesion onto the MD membrane. Granular activated carbon (GAC) pretreatment helped in reducing organic contents of WWROC by 46–50%, and adsorbed a range of hydrophobic and hydrophilic micropollutants. This ensured high quality water production by MD (micropollutants-free) and enhanced its reuse potential. The MD concentrated WWROC was suitable for selective ion precipitation, promising a near zero liquid discharge in WRPs.

  6. Biological Treatment of Water Disinfection Byproducts using ...

    Science.gov (United States)

    Major disinfection by-products (DBPs) from the chlorination process of drinking water include trihalomethanes (THMs) and haloacetic acides (HAA5). THMs mainly consist of chloroform, and other harsh chemicals. Prolonged consumptions of drinking water containing high levels of THMs has been linked with diseases of the liver, kidneys, bladder, or central nervous system and may increase likelihood of cancer. A risk also exists for THMs exposure via inhalation while showering, bathing or washing clothes and dishes. Due to these risks, the U.S. EPA regulate THMs content in drinking water. This research investigates biological degradation of THM using chloroform as a model compound. The study aims to decrease possible risks of THMs through filtration. Throughout this year’s presentations, there is a common theme of health and safety concerns. UC researchers are working hard to clean water ways of naturally occurring contaminates as well as man-made toxins found in our waterways. The significance of these presentations translates into the promise of safer environments, and more importantly saved lives, as UC’s faculty continues to produce real-world solutions to problems threatening the world around us. A biotech process has been developed and demonstrated that effectively remove and treat volatile disinfection by-products from drinking water. The process strips low concentration disinfection by-products, such as trihalomethanes, that are formed during the chlori

  7. Green Walls as an Approach in Grey Water Treatment

    Science.gov (United States)

    Rysulova, Martina; Kaposztasova, Daniela; Vranayova, Zuzana

    2017-10-01

    Grey water contributes significantly to waste water parameters such as biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total phosphorus (Ptotal), total nitrogen (Ntotal), ammonium, boron, metals, salts, surfactants, synthetic chemicals, oils and greases, xenobiotic substances and microorganisms. Concentration of these pollutants and the water quality highlights the importance of treatment process in grey water systems. Treatment technologies operating under low energy and maintenance are usually preferred, since they are more cost effective for users. Treatment technologies based on natural processes represent an example of such technology including vegetated wall. Main aim of this paper is to introduce the proposal of vegetated wall managing grey water and brief characteristic of proposed system. Is expected that prepared experiment will establish the purifying ability and the potential of green wall application as an efficient treatment technology.

  8. THMs assessment in Khuzestan rural water treatment plants

    Directory of Open Access Journals (Sweden)

    Mehdi Ahmadi

    2012-01-01

    Full Text Available Aims: The trihalomethanes (THMs concentration was investigated in some of rural water treatment plants in Khuzestan. Materials and Methods: Fifteen of the water treatment plants with the same drinking water source (Karoon river were selected for analysis of THMs to assess the levels and the relationship between THMs and total organic carbon (TOC, pH, temperature, chlorination dose, and free chlorine residue. Results: THMs ranged from 1.8 to 219 mg/l in winter and 1.7 to 98 in summer, where the level in some treatment plants is higher than the Maximum Concentration Level (MCL. The ratio of total THMs levels was significantly correlated with temperature, pH, chlorination dose, and free chlorine residue, but negative correlation with TOC. Conclusion: Epidemiological studies using total THMs levels should be considered in the analysis of water treatment plant′s results, and regulatory check of this parameter with drinking water guidelines.

  9. Acid mine water aeration and treatment system

    Science.gov (United States)

    Ackman, Terry E.; Place, John M.

    1987-01-01

    An in-line system is provided for treating acid mine drainage which basically comprises the combination of a jet pump (or pumps) and a static mixer. The jet pump entrains air into the acid waste water using a Venturi effect so as to provide aeration of the waste water while further aeration is provided by the helical vanes of the static mixer. A neutralizing agent is injected into the suction chamber of the jet pump and the static mixer is formed by plural sections offset by 90 degrees.

  10. Climate Adaptation Capacity for Conventional Drinking Water Treatment Facilities

    Science.gov (United States)

    Levine, A.; Goodrich, J.; Yang, J.

    2013-12-01

    Water supplies are vulnerable to a host of climate- and weather-related stressors such as droughts, intense storms/flooding, snowpack depletion, sea level changes, and consequences from fires, landslides, and excessive heat or cold. Surface water resources (lakes, reservoirs, rivers, and streams) are especially susceptible to weather-induced changes in water availability and quality. The risks to groundwater systems may also be significant. Typically, water treatment facilities are designed with an underlying assumption that water quality from a given source is relatively predictable based on historical data. However, increasing evidence of the lack of stationarity is raising questions about the validity of traditional design assumptions, particularly since the service life of many facilities can exceed fifty years. Given that there are over 150,000 public water systems in the US that deliver drinking water to over 300 million people every day, it is important to evaluate the capacity for adapting to the impacts of a changing climate. Climate and weather can induce or amplify changes in physical, chemical, and biological water quality, reaction rates, the extent of water-sediment-air interactions, and also impact the performance of treatment technologies. The specific impacts depend on the watershed characteristics and local hydrological and land-use factors. Water quality responses can be transient, such as erosion-induced increases in sediment and runoff. Longer-term impacts include changes in the frequency and intensity of algal blooms, gradual changes in the nature and concentration of dissolved organic matter, dissolved solids, and modulation of the microbiological community structure, sources and survival of pathogens. In addition, waterborne contaminants associated with municipal, industrial, and agricultural activities can also impact water quality. This presentation evaluates relationships between climate and weather induced water quality variability and

  11. Substrate-adsorbate coupling in CO-adsorbed copper

    CERN Document Server

    Lewis, S P; Lewis, Steven P.; Rappe, Andrew M.

    1996-01-01

    The vibrational properties of carbon monoxide adsorbed to the copper (100) surface are explored within density functional theory. Atoms of the substrate and adsorbate are treated on an equal footing in order to examine the effect of substrate--adsorbate coupling. This coupling is found to have a significant effect on the vibrational modes, particularly the in-plane frustrated translation, which mixes strongly with substrate phonons and broadens into a resonance. The predicted lifetime due to this harmonic decay mechanism is in excellent quantitative agreement with experiment.

  12. Ballast Water Treatment Corrosion Scoping Study

    Science.gov (United States)

    2011-10-01

    Office of Environmental Standards, 2009) Organism Size > 50μm* > 10μm & ≤ 50μm ≤ 10μm Pathogens and Indicators Toxicogenic V. cholerae O1...type of corrosion is generally associated with the presence of small volumes of stagnant water beneath deposits and seals, in crevices, or where nuts

  13. REVIEW OF EXISTING LCA STUDIES ON WASTE WATER TREATMENT TECHNOLOGIES

    DEFF Research Database (Denmark)

    Larsen, Henrik Fred; Hauschild, Michael Zwicky

    The EU research project “NEPTUNE” is related to the EU Water Framework Directive and focused on the development of new waste water treatment technologies (WWTT) for municipal waste water. The sustainability of these WWTTs is going to be assessed by the use of life cycle assessment (LCA). New life...... importance of the different life cycle stages and the individual impact categories in the total impact from the waste water treatment, and the degree to which micropollutants, pathogens and whole effluent toxicity have been included in earlier studies. The results show that more than 30 different WWTT (and...

  14. Potential of polyaniline modified clay nanocomposite as a selective decontamination adsorbent for Pb(II) ions from contaminated waters; kinetics and thermodynamic study

    National Research Council Canada - National Science Library

    Somayeh Piri; Zahra Alikhani Zanjani; Farideh Piri; Abbasali Zamani; Mohamadreza Yaftian; Mehdi Davari

    2016-01-01

    .... In this article the synthesis and characterization of conductive polyaniline/clay (PANI/clay) as a hybrid nanocomposite with extended chain conformation and its application for water purification are presented...

  15. Water-resistance of macromolecules adsorbed on CH3NH3PbI3 surfaces: A first-principles study

    Science.gov (United States)

    Chen, Po-Tuan; Yung, Tung-Yuan; Liu, Ting-Yu; Sher, Chin-Wei; Hayashi, Michitoshi

    2017-10-01

    Encapsulation within resin films is a promising approach for isolating perovskite materials from water. To gain fundamental insight into these systems, we performed first-principles calculations of macromolecule (polymerized siloxane; epoxy cured by phthalic anhydride; graphene sheet) coatings for the waterproofing of methylammonium lead iodide perovskite (MAPbI3) surfaces. Our calculations reveal that alternating attractive/resistant functional groups on the siloxane- or epoxy-modified MAPbI3 surfaces hinder the water diffusion process. Moreover, we examined a no-defect graphene sheet for its ability to isolate MAPbI3 from water molecules. The hydrophobicity of the graphene resulted in water molecules forming clusters, rather than dispersing, upon the sheet.

  16. Waste Water Treatment of Dye Contamination

    Directory of Open Access Journals (Sweden)

    Pattana Boonyaprapa

    2009-01-01

    Full Text Available The objectives of this research were to study tie-dye process data and wastewater characteristics from 60 entrepreneurs, and to study the colour density treatment in pilot scale by using upflow anaerobic filters. From 60 filled-out questionnaires, it was found that all tie-dye entrepreneurs used reactive dyes by a hot method. Ninety-eight percent of the tie-dye enterpreneurs produced wastewater at the rate of not more than 1500 liters per day. All of them lacked tie-dye wastewater treatment systems. Eighty-five percent of tie-dye entrepreneurs agreed that there must be wastewater treatment before release into the environment. From group discussions, it was found that the entrepreneurs realized the wastewater problem and wanted to carry out environment friendly tie-dyeing. Our study demonstrated that the average value of the colour density, chemical oxygen demand (COD, total dissolved solids (TDS and pH of the wastewater characteristics were 170 SU (space units, 1584 mg/l, 2487 mg/l and 8, respectively. For the upflow anaerobic filter, 5 sets of experiments, with 24 hours retention time, were designed, with 0, 1, 2, 3 and 4 % of cow’s feces ferment, respectively (sets 1st-5th. The result showed decreasing colour densities from 170 SU to 160 SU (dark colour, 60 SU (very light colour, 12 SU (no colour, 10 SU (no colour and 10 SU (no colour, respectively. We conclude that the upflow anaerobic filter, containing 2% cow’s feces ferment is an efficient way to reduce colour density of the wastewater. Mixing cow’s feces ferment with tie-dye wastewater increased COD and TDS in wastewater. Mean COD was increased by residual organic matter from 1584 mg/l (before treatment to (after-treatment, sets 2nd- 5th 1600 mg/l, 1680 mg/l, 1710 mg/l and 1750 mg/l, respectively. COD aftertreatment was higher than the industrial effluence standard (400 mg/l. Further treatment COD might include wetland procedures. TDS was increased by some residual organic matter

  17. Evaluation of the adsorbent properties of a zeolite rock modified for the removal of the azo dyes as water pollutants; Evaluacion de las propiedades adsorbentes de una roca zeolitica modificada para la remocion de colorantes azoicos como contaminantes del agua

    Energy Technology Data Exchange (ETDEWEB)

    Torres P, J

    2005-07-01

    At the moment some investigations which make reference to the removal of dyes for diverse adsorbent materials; as well as the factors that influence in the sorption process, considering the type so much of dye as those characteristics of the adsorbent material. In this work were investigated those adsorbent properties of a zeolite rock coming from San Luis Potosi State for the removal of azo dyes, using as peculiar cases the Red 40 (Red Allura) and the Yellow 5 (Tartrazine); for it were determined kinetic parameters and the sorption isotherms, as well as the sorption mechanisms involved in each case, between the dyes and the zeolite rock. In this work also it was considered the characterization before and after to removal of color from the water, through advanced analytical techniques such as the scanning electron microscopy of high vacuum (SEM), elementary microanalysis (EDS) and X-ray diffraction (XRD). The experimental part of the work fundamentally consisted, in the conditioning with a NaCl solution and later on the modification with HDTMA-Br of the natural zeolite rock, for then to put it in contact with solutions of the dyes R-40 and A-5, varying so much the contact times as the concentrations; the quantification of sodium in the liquid phase after the modification of the zeolite rock to determine the capacity of external cation exchange (CICE) it was carried out by means of the atomic absorption spectroscopy technique (EAA), and the quantification of the surfactant and the dyes in the liquid phase, it was carried out by means of the UV-vis spectrophotometry technique. It was found that the kinetic model that better it describes the process of sorption of R-40 and A-5 for the modified zeolite rock with HDTMA-Br, leaving of monocomponent and bi component solutions, it is the pseudo- second order. Inside of the obtained results for the sorption isotherms, as much the dye R-40 as the dye A-5 its presented a better adjustment to the Langmuir model. In what refers

  18. REVIEW ON NATURAL METHODS FOR WASTE WATER TREATMENT

    Directory of Open Access Journals (Sweden)

    Ashwani Kumar Dubey

    2014-01-01

    Full Text Available In Ethiopia, the most common method of disposal of waste water is by land spreading. This treatment method has numerous problems, namely high labor requirements and the potential for eutrophication of surface an d ground waters. Constructed wetlands are commonl y used for treatment of seconda ry municipal wastewaters and they have been gaining popularity for treatment of agricultural wastewaters in Ethiopia. Intermittent sand filtration may offer an alternative to traditional treatment methods. As well as providing comparable treatment performance, they also have a smaller footprint, due to the substantially higher organic loading rates that may be applied to their surfaces. Th is paper discusses the performance and design criteria of constructed wetlands for the treatment of domestic and agricultural wastewater, and sand filters for the treatment of domestic wastewater. It also proposes sand filtration as an alt ernative treatment mechanism for agricultural wa stewater and suggests design guide lines.

  19. Defluoridation of groundwater using brick powder as an adsorbent.

    Science.gov (United States)

    Yadav, Asheesh Kumar; Kaushik, C P; Haritash, Anil Kumar; Kansal, Ankur; Rani, Neetu

    2006-02-06

    Defluoridation of groundwater using brick powder as an adsorbent was studied in batch process. Different parameters of adsorption, viz. effect of pH, effect of dose and contact time were selected and optimized for the study. Feasible optimum conditions were applied to two groundwater samples of high fluoride concentration to study the suitability of adsorbent in field conditions. Comparison of adsorption by brick powder was made with adsorption by commercially available activated charcoal. In the optimum condition of pH and dose of adsorbents, the percentage defluoridation from synthetic sample, increased from 29.8 to 54.4% for brick powder and from 47.6 to 80.4% for commercially available activated charcoal with increasing the contact time starting from 15 to 120 min. Fluoride removal was found to be 48.73 and 56.4% from groundwater samples having 3.14 and 1.21 mg l(-1) fluoride, respectively, under the optimized conditions. Presence of other ions in samples did not significantly affect the deflouridation efficiency of brick powder. The optimum pH range for brick powder was found to be 6.0-8.0 and adsorption equilibrium was found to be 60 min. These conditions make it very suitable for use in drinking water treatment. Deflouridation capacity of brick powder can be explained on the basis of the chemical interaction of fluoride with the metal oxides under suitable pH conditions. The adsorption process was found to follow first order rate mechanism as well as Freundlich isotherm.

  20. Inorganic chemically active adsorbents (ICAAs)

    Energy Technology Data Exchange (ETDEWEB)

    Ally, M.R. [Oak Ridge National Lab., TN (United States); Tavlarides, L.

    1997-10-01

    Oak Ridge National Laboratory (ORNL) researchers are developing a technology that combines metal chelation extraction technology and synthesis chemistry. They begin with a ceramic substrate such as alumina, titanium oxide or silica gel because they provide high surface area, high mechanical strength, and radiolytic stability. One preparation method involves silylation to hydrophobize the surface, followed by chemisorption of a suitable chelation agent using vapor deposition. Another route attaches newly designed chelating agents through covalent bonding by the use of coupling agents. These approaches provide stable and selective, inorganic chemically active adsorbents (ICAAs) tailored for removal of metals. The technology has the following advantages over ion exchange: (1) higher mechanical strength, (2) higher resistance to radiation fields, (3) higher selectivity for the desired metal ion, (4) no cation exchange, (5) reduced or no interference from accompanying anions, (6) faster kinetics, and (7) easy and selective regeneration. Target waste streams include metal-containing groundwater/process wastewater at ORNL`s Y-12 Plant (multiple metals), Savannah River Site (SRS), Rocky Flats (multiple metals), and Hanford; aqueous mixed wastes at Idaho National Engineering Laboratory (INEL); and scrubber water generated at SRS and INEL. Focus Areas that will benefit from this research include Mixed Waste, and Subsurface Contaminants.

  1. Arsenic Adsorption and Desorption by Drinking Water Treatment Residuals: Incubation Studies

    Science.gov (United States)

    Vandanapu, V.; Sarkar, D.; Datta, R.; Makris, K.

    2005-05-01

    Arsenic (As) has been used for a long time in agricultural practices, primarily to control pests and noxious weeds. In many cases, the indiscriminate usage of toxic arsenical compounds has left a legacy of contaminated soils. Recent awareness of the toxicity of As at much lower concentrations than previously deemed to be dangerous has led to increased interest in the environmental chemistry of As. The immediate challenge, as perceived by various regulatory bodies is to develop a cost-effective, reliable and environmentally sound approach to cleaning up such contaminated soils. In-situ immobilization technologies are an attractive alternative to conventional remediation methods. One of the most interesting of these in-situ techniques is the use of Water Treatment Residuals (WTRs). The WTRs are by-products of drinking water purification processes and generally contain sediments, organic carbon, and Al/Fe oxides. The oxides are typically amorphous (with very high specific surface area) and have tremendous affinity for oxyanions (e.g., arsenate), due to their high positive surface charge. Recent studies conducted by our group have suggested that WTRs retain As and decrease arsenic mobility. However, a better understanding of As adsorption/desorption by WTRs is necessary for effective implementation of appropriate in-situ remedial strategies. Hence, the present study examines the potential use of WTRs (Al-WTR and Fe-WTR) as adsorbents for the removal of arsenate in solutions. Furthermore, it investigates the extent of desorption of the pre-adsorbed arsenate onto the WTR surfaces. Effects of various key parameters, such as solid solution ratio, equilibration time and arsenic concentration were examined to achieve the optimized conditions for arsenate adsorption. Preliminary batch adsorption experiments showed the optimum equilibration time to be 24 h and the solid/solution ratio to be 1:5 for arsenate adsorption. Sorption data has been evaluated using both Langmuir and

  2. Waste Water Treatment of Dye Contamination

    OpenAIRE

    Pattana Boonyaprapa

    2009-01-01

    The objectives of this research were to study tie-dye process data and wastewater characteristics from 60 entrepreneurs, and to study the colour density treatment in pilot scale by using upflow anaerobic filters. From 60 filled-out questionnaires, it was found that all tie-dye entrepreneurs used reactive dyes by a hot method. Ninety-eight percent of the tie-dye enterpreneurs produced wastewater at the rate of not more than 1500 liters per day. All of them lacked tie-dye wastewater treatment s...

  3. Current status of adsorbent for metal ions with radiation grafting and crosslinking techniques

    Science.gov (United States)

    Seko, Noriaki; Tamada, Masao; Yoshii, Fumio

    2005-07-01

    Removal of toxic metals from streaming water and ground water is important task to preserve environment. Radiation processing of grafting and crosslinking can synthesis adsorbent having high performances. Graft adsorbent can be synthesized by using the conventional polymer like polyethylene having variety shapes such as membrane, cloth, and fiber. Especially, the obtained fibrous adsorbent has 100 times higher rate of adsorption than that of commercialized resin. Fibrous adsorbent of iminodiacetate was applied to the removal of cadmium from the scallop waste. Furthermore, the amidoxime adsorbent is useful for recovery of rare metals such as uranium and vanadium in seawater. Novel fibrous adsorption for arsenic was synthesized by direct grafting of phosphoric monomer and following zirconium-loading. Crosslinked natural polymers like carboxymethyl chitin-chitosan in the paste-like state are applicable for the metal adsorbent. This adsorbent can be biodegraded after usage.

  4. Cross-linked cyclodextrin-based material for treatment of metals and organic substances present in industrial discharge waters

    Directory of Open Access Journals (Sweden)

    Élise Euvrard

    2016-08-01

    Full Text Available In this study, a polymer, prepared by crosslinking cyclodextrin (CD by means of a polycarboxylic acid, was used for the removal of pollutants from spiked solutions and discharge waters from the surface treatment industry. In spiked solutions containing five metals, sixteen polycyclic aromatic hydrocarbons (PAH and three alkylphenols (AP, the material exhibited high adsorption capacities: >99% of Co2+, Ni2+ and Zn2+ were removed, between 65 and 82% of the PAHs, as well as 69 to 90% of the APs. Due to the structure of the polymer and its specific characteristics, such as the presence of carboxylic groups and CD cavities, the adsorption mechanism involves four main interactions: ion exchange, electrostatic interactions and precipitation for metal removal, and inclusion complexes for organics removal. In industrial discharge waters, competition effects appeared, especially because of the presence of calcium at high concentrations, which competed with other pollutants for the adsorption sites of the adsorbent.

  5. Cross-linked cyclodextrin-based material for treatment of metals and organic substances present in industrial discharge waters

    Science.gov (United States)

    Euvrard, Élise; Morin-Crini, Nadia; Druart, Coline; Bugnet, Justine; Martel, Bernard; Cosentino, Cesare; Moutarlier, Virginie

    2016-01-01

    Summary In this study, a polymer, prepared by crosslinking cyclodextrin (CD) by means of a polycarboxylic acid, was used for the removal of pollutants from spiked solutions and discharge waters from the surface treatment industry. In spiked solutions containing five metals, sixteen polycyclic aromatic hydrocarbons (PAH) and three alkylphenols (AP), the material exhibited high adsorption capacities: >99% of Co2+, Ni2+ and Zn2+ were removed, between 65 and 82% of the PAHs, as well as 69 to 90% of the APs. Due to the structure of the polymer and its specific characteristics, such as the presence of carboxylic groups and CD cavities, the adsorption mechanism involves four main interactions: ion exchange, electrostatic interactions and precipitation for metal removal, and inclusion complexes for organics removal. In industrial discharge waters, competition effects appeared, especially because of the presence of calcium at high concentrations, which competed with other pollutants for the adsorption sites of the adsorbent. PMID:27829889

  6. Effect of nitrogen doping on titanium carbonitride-derived adsorbents used for arsenic removal

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jisun [Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, Soonjae [Center for Water Resource Cycle Research, Korea Institute of Science and Technology, Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Choi, Keunsu [Computational Science Research Center, Korea Institute of Science and Technology, Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Kim, Jinhong [Samsung Electronics Co.Ltd.,(Maetan dong) 129, Samsung-ro Yeongtong-gu, Suwonsi, Gyeonggi-do 443-742, Repubilc of Korea (Korea, Republic of); Ha, Daegwon [Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, Chang-Gu [Center for Water Resource Cycle Research, Korea Institute of Science and Technology, Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); An, Byungryul [Department of Civil Engineering, Sangmyung University, Cheonan, Chungnam 31066 (Korea, Republic of); Lee, Sang-Hyup [Center for Water Resource Cycle Research, Korea Institute of Science and Technology, Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Mizuseki, Hiroshi, E-mail: mizuseki@kist.re.kr [Computational Science Research Center, Korea Institute of Science and Technology, Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Choi, Jae-Woo, E-mail: plead36@kist.re.kr [Center for Water Resource Cycle Research, Korea Institute of Science and Technology, Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of); Department of Energy and Environmental Engineering, University of Science and Technology (UST), Daejeon 305-350 (Korea, Republic of); Kang, Shinhoo, E-mail: shinkang@snu.ac.kr [Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2016-01-25

    Highlights: • The N-doping can improve the As adsorption performance of carbon-based materials. • The material features high micro- and small meso-pores with exceptional surface area. • Pyrrolic N atoms distributed uniformly on the micropores act as adsorption sites. • The synthesis temperature affected pore properties and surface functional groups. - Abstract: Arsenic in water and wastewater is considered to be a critical contaminant as it poses harmful health risks. In this regard, to meet the stringent regulation of arsenic in aqueous solutions, nitrogen doped carbon-based materials (CN) were prepared as adsorbents and tested for the removal of arsenic ion from aqueous solutions. Nitrogen-doped carbon (CNs) synthesized by chlorination exhibited well-developed micro- and small meso-pores with uniform pore structures. The structure and characteristics of the adsorbents thus developed were confirmed by field-emission scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller analysis, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. Among the CNs developed, CN700 exhibited high adsorption capacity for arsenic (31.08 mg/g). The adsorption efficiency for arsenic ion was confirmed to be affected by pyrrolic nitrogen and micro-pores. These results suggest that CNs are useful adsorbents for the treatment of arsenic, and in particular, CN700 demonstrates potential for application as an adsorbent for the removal of anionic heavy metals from wastewater and sewage.

  7. Ships' Ballast Water Treatment by Chlorination Can Generate Toxic Trihalomethanes.

    Science.gov (United States)

    Hernandez, Marco R; Ismail, Nargis; Drouillard, Ken G; MacIsaac, Hugh J

    2017-08-01

    The International Maritime Organization (IMO) will enforce a new abundance-based performance standard for ballast water in September, 2017. Strong oxidants, like chlorine, have been proposed as a method for achieving this standard. However chlorine treatment of ballast water can produce hazardous trihalomethanes. We assessed maximum trihalomethane production from one chlorine dose for three types of ballast water (fresh, brackish and marine) and three levels of total organic carbon (TOC) concentration (natural, filtered, enhanced). While the current standard test considers a 5 day voyage, there is a high possibility of shorter trips and sudden change of plans that will release treated waters in the environment. Water source and TOC significantly affected trihalomethane production, with the highest amounts generated in brackish waters and enhanced TOC concentration. The concentration of brominated trihalomethanes increased from background levels and was highest in brackish water, followed by marine and fresh water.

  8. Recovery of Alum Coagulant from Water Treatment Plant Sludge: A Greener Approach for Water Purification

    OpenAIRE

    Smita Joshi; Kriti Shrivastava

    2011-01-01

    The present work is based on Alum Recovery from the sludge obtained from Shyamala Water Treatment Plant by Acidic and Alkaline methods. In the acidic and alkaline method, the maximum recovery of alum coagulant is found to be 84.18% and 76.98% respectively. The recovered alum is as efficient as commercial alum and can be used again as coagulant for Water Treatment. This recovery can solve the vast problem of WTP (Water Treatment Plant) sludge management together with the problem of water pollu...

  9. Optimizing Conditions to Cholesterol Adsorbed with Carboxymethyl Chitosan

    Directory of Open Access Journals (Sweden)

    Mardiyah Kurniasih

    2016-05-01

    Full Text Available A research on optimizing conditions to cholesterol adsorbed have been performed. Optimization was performed by varying: contact time, adsorbent weight and temperature of the system's. A full factorial experimental design was used in this study. Characterization performed on the synthesized chitosan and carboxymethyl chitosan including FTIR, water content, ash content, solubility, porosity, and swelling effect. The results showed that carboxymethyl chitosan able to adsorb cholesterol under conditions optimal adsorbent with cholesterol ratio (1:200 with a contact time of 90 minutes at temperature of 40 °C. Meanwhile, at a temperature of 55 °C carboxymethyl chitosan capable of adsorb cholesterol under conditions optimal adsorbent with cholesterol ratio (1:300 with a contact time of 30 minutes. Chitosan and carboxymethyl chitosan synthesized has a water content of 7.4 and 10.2%, ash content of 0.14 and 2.29%, solubility in distilled water at 1.10-5and 1.98.10-3%, solubility in acetic acid 0.02 and 0.04%, porosity at 88.3% and 88.8%, and swelling at 163.13 and 182.98%.

  10. Economies of density for on-site waste water treatment

    NARCIS (Netherlands)

    Eggimann, Sven; Truffer, Bernhard|info:eu-repo/dai/nl/6603148005; Maurer, Max

    2016-01-01

    Decentralised wastewater treatment is increasingly gaining interest as a means of responding to sustainability challenges. Cost comparisons are a crucial element of any sustainability assessment. While the cost characteristics of centralised waste water management systems (WMS) have been studied

  11. Produced water treatment for beneficial use: emulsified oil removal

    NARCIS (Netherlands)

    Waisi, Basma

    2016-01-01

    The development of novel carbon material, high accessible surface area, interconnected porosity, and stable nanofiber nonwoven media for emulsified oil droplets separation from oily wastewater, in particular for oilfields produced water treatment, is discussed in this thesis. Firstly, the quantity

  12. Safe Drinking Water Information System (SDWIS) Sewer Treatment Plants

    Data.gov (United States)

    U.S. Environmental Protection Agency — This is a point feature dataset showing the locations of sewer treatment plants. These facility locations are part of the safe drinking water information system...

  13. Crow Municipal Rural & Industrial Pilot Water Treatment Plant NPDES Permit

    Science.gov (United States)

    Under NPDES permit MT-0031827, the Crow Indian Tribe is authorized to discharge from the Crow Municipal Rural & Industrial (MR&I) Pilot Water Treatment Plant in Bighorn County, Montana to the Bighorn River.

  14. Microbial pathogens in source and treated waters from drinking water treatment plants in the US

    Science.gov (United States)

    An occurrence survey was conducted on selected pathogens in source and treated drinking water collected from 25 drinking water treatment plants (DWTPs) in the United States. Water samples were analyzed for the protozoa Giardia and Cryptosporidium (EPA Method 1623); the fungi Asp...

  15. Effect of magnetic treatment of water on chemical properties of water ...

    African Journals Online (AJOL)

    Effect of magnetic treatment of water on chemical properties of water and sodium adsorption ratio. ... All the cations (Calcium, Sodium, Magnesium, Potassium, Cadmium and Lead) were determined using the Standard Methods for Examination of Water and ... The mean values of nitrate from MTW were 43.07, 43.04.

  16. The use of Crambe abyssinica seeds as adsorbent in the removal of metals from waters Uso de sementes de Crambe abyssinica como adsorvente na remoção de metais de águas

    Directory of Open Access Journals (Sweden)

    Affonso C. Gonçalves Jr.

    2013-03-01

    Full Text Available This study aimed to evaluate the efficacy of crambe seeds (Crambe abyssinica Hochst as adsorbent material in the removal of the toxic metals cadmium, lead and chromium from contaminated solutions. The byproduct was obtained from oil extraction of crambe seeds in a Soxhlet system. In kinetic tests, the adsorbent masses had varied in solutions containing the metals under pH 5.0 and 7.0. Metal concentrations were determined by flame atomic absorption spectrometry (FAAS. According to optimal conditions found, the adsorption assays were performed for obtaining the isotherms of each metal, which were linearized in agreement with the mathematical models of Langmuir and Freundlich. According to the obtained results, the adsorbent was effective in removing the assessed metals in aqueous solutions, being feasible its employment as an alternative material for the adsorption of metals, besides being a byproduct, which has undergone no prior treatment.Objetivou-se, neste trabalho, avaliar a eficácia do uso das sementes de crambe (Crambe abyssinica Hochst como material adsorvente na remoção dos metais pesados tóxicos cádmio, chumbo e cromo de soluções contaminadas. Obteve-se a torta a partir da extração do óleo das sementes de crambe em sistema tipo Soxhlet. Nos testes cinéticos as massas do adsorvente variaram em soluções contendo os metais em condições de pH 5.0 e 7.0. As concentrações dos metais foram determinadas por espectrometria de absorção atômica modalidade chama (EAA/chama. De acordo com as condições ótimas encontradas ensaios de adsorção foram realizados para a construção das isotermas de cada metal as quais, por sua vez, foram linearizadas conforme os modelos matemáticos de Langmuir e Freundlich. Com base nos resultados obtidos concluiu-se que o adsorvente foi eficaz na remoção dos metais estudados em soluções aquosas, sendo viável sua utilização como material alternativo para adsorção dos metais pesados, al

  17. Waste Water Treatment Plants and the Smart Grid

    DEFF Research Database (Denmark)

    Halvgaard, Rasmus; Tychsen, Peter; Munk-Nielsen, Thomas

    2014-01-01

    power production. The energy-heavy processes for waste water transport and treatment could potentially provide a flexible operation with storage capabilities and be a valuable asset to a Smart Grid. In order to enable Waste Water Treatment Plants (WWTPs) as flexible prosumers in the future Smart Grid......, we must update their process control system to model based predictive control that monitors the changed flexible operation and plans ahead. The primary aim of a WWTP is to treat the incoming waste water as much as possible to ensure a sufficient effluent water quality and protect the environment...... of the recipient. The secondary aim is to treat the waste water using as little energy as possible. In the future waste water will be considered an energy resource, that contains valuable nutrients convertible to green biogas and in turn electricity and heat. In a Smart Grid consuming or producing energy...

  18. Linking ceragenins to water-treatment membranes to minimize biofouling.

    Energy Technology Data Exchange (ETDEWEB)

    Hibbs, Michael R.; Altman, Susan Jeanne; Feng, Yanshu (Brigham Young University, Provo, Utah); Savage, Paul B. (Brigham Young University, Provo, Utah); Pollard, Jacob (Brigham Young University, Provo, Utah); Branda, Steven S.; Goeres, Darla (Montana State University, Bozeman, MT); Buckingham-Meyer, Kelli (Montana State University, Bozeman, MT); Stafslien, Shane (North Dakota State University, Fargo, ND); Marry, Christopher; Jones, Howland D. T.; Lichtenberger, Alyssa; Kirk, Matthew F.; McGrath, Lucas K. (LMATA, Albuquerque, NM)

    2012-01-01

    Ceragenins were used to create biofouling resistant water-treatment membranes. Ceragenins are synthetically produced antimicrobial peptide mimics that display broad-spectrum bactericidal activity. While ceragenins have been used on bio-medical devices, use of ceragenins on water-treatment membranes is novel. Biofouling impacts membrane separation processes for many industrial applications such as desalination, waste-water treatment, oil and gas extraction, and power generation. Biofouling results in a loss of permeate flux and increase in energy use. Creation of biofouling resistant membranes will assist in creation of clean water with lower energy usage and energy with lower water usage. Five methods of attaching three different ceragenin molecules were conducted and tested. Biofouling reduction was observed in the majority of the tests, indicating the ceragenins are a viable solution to biofouling on water treatment membranes. Silane direct attachment appears to be the most promising attachment method if a high concentration of CSA-121a is used. Additional refinement of the attachment methods are needed in order to achieve our goal of several log-reduction in biofilm cell density without impacting the membrane flux. Concurrently, biofilm forming bacteria were isolated from source waters relevant for water treatment: wastewater, agricultural drainage, river water, seawater, and brackish groundwater. These isolates can be used for future testing of methods to control biofouling. Once isolated, the ability of the isolates to grow biofilms was tested with high-throughput multiwell methods. Based on these tests, the following species were selected for further testing in tube reactors and CDC reactors: Pseudomonas ssp. (wastewater, agricultural drainage, and Colorado River water), Nocardia coeliaca or Rhodococcus spp. (wastewater), Pseudomonas fluorescens and Hydrogenophaga palleronii (agricultural drainage), Sulfitobacter donghicola, Rhodococcus fascians, Rhodobacter

  19. Factor Affecting Textile Dye Removal Using Adsorbent From Activated Carbon: A Review

    Directory of Open Access Journals (Sweden)

    Mohammad Razi Mohd Adib

    2017-01-01

    Full Text Available Industrial company such as textile, leather, cosmetics, paper and plastic generated wastewater containing large amount of dye colour. The removal of dye materials are importance as the presence of this kind of pollutant influence the quality of water and makes it aesthetically unpleasant. As their chemical structures are complicated, it is difficult to treat dyes with municipal waste treatment operations. Even a small quantity of dye does cause high visibility and undesirability. There have been various treatment technique reviewed for the removal of dye in wastewater. However, these treatment process has made it to another expensive treatment method. This review focus on the application of adsorbent in dye removal from textile wastewater as the most economical and effective method, adsorption has become the most preferred method to remove dye. The review provides literature information about different basis materials used to produce activated carbon like agricultural waste and industrial waste as well as the operational parameters factors in term of contact time, adsorbent dosage, pH solution and initial dye concentration that will affect the process in removing textile dye. This review approach the low cost and environmental friendly adsorbent for replacing conventional activated carbon.

  20. Arsenic Remediation by Synthetic and Natural Adsorbents

    Directory of Open Access Journals (Sweden)

    Muhammad Saqaf Jagirani

    2017-06-01

    Full Text Available The contagion of toxic metals in water is a serious environmental and health concern and threatening problem worldwide. Particularly arsenic contamination in ground water has became great dilemma in the earlier decades. With advent in research for arsenic remediation, standard of drinking water is improving and now reduced to few parts per million (ppm level of arsenic in drinking water sources. However, due to continuous enhancement in environmental pollution, remediation techniques are still needed to achieve the drinking water quality standard. Development of novel and economically feasible removal techniques or materials for selective separation of this toxic specie has been the main focus of research. Several arsenic removal techniques, including membrane separation, coagulation, precipitation, anion exchange have been developed. The aim of this article is to review briefly arsenic chemistry and previous and current available technologies that have been reported various low-cost adsorbents for arsenic removal.

  1. Changes in water quality in the Owabi water treatment plant in Ghana

    Science.gov (United States)

    Akoto, Osei; Gyamfi, Opoku; Darko, Godfred; Barnes, Victor Rex

    2017-03-01

    The study was conducted on the status of the quality of water from the Owabi water treatment plant that supplies drinking water to Kumasi, a major city in Ghana, to ascertain the change in quality of water from source to point-of-use. Physico-chemical, bacteriological water quality parameters and trace metal concentration of water samples from five different treatment points from the Owabi water treatment plant were investigated. The raw water was moderately hard with high turbidity and colour that exceeds the WHO guideline limits. Nutrient concentrations were of the following order: NH3 < NO2 - < NO3 - < PO4 3- < SO4 2- and were all below WHO permissible level for drinking water in all the samples at different stages of treatment. Trace metal concentrations of the reservoir were all below WHO limit except chromium (0.06 mg/L) and copper (0.24 mg/L). The bacteriological study showed that the raw water had total coliform (1,766 cfu/100 mL) and faecal coliform (257 cfu/100 mL) that exceeded the WHO standard limits, rendering it unsafe for domestic purposes without treatment. Colour showed strong positive correlation with turbidity ( r = 0.730), TSS ( r ≥ 0.922) and alkalinity (0.564) significant at p < 0.01. The quality of the treated water indicates that colour, turbidity, Cr and Cu levels reduced and fall within the WHO permissible limit for drinking water. Treatment process at the water treatment plant is adjudged to be good.

  2. Water drinking as a treatment for orthostatic syndromes

    Science.gov (United States)

    Shannon, John R.; Diedrich, Andre; Biaggioni, Italo; Tank, Jens; Robertson, Rose Marie; Robertson, David; Jordan, Jens

    2002-01-01

    PURPOSE: Water drinking increases blood pressure in a substantial proportion of patients who have severe orthostatic hypotension due to autonomic failure. We tested the hypothesis that water drinking can be used as a practical treatment for patients with orthostatic and postprandial hypotension, as well as those with orthostatic tachycardia. SUBJECTS AND METHODS: We studied the effect of drinking water on seated and standing blood pressure and heart rate in 11 patients who had severe orthostatic hypotension due to autonomic failure and in 9 patients who had orthostatic tachycardia due to idiopathic orthostatic intolerance. We also tested the effect of water drinking on postprandial hypotension in 7 patients who had autonomic failure. Patients drank 480 mL of tap water at room temperature in less than 5 minutes. RESULTS: In patients with autonomic failure, mean (+/- SD) blood pressure after 1 minute of standing was 83 +/- 6/53 +/- 3.4 mm Hg at baseline, which increased to 114 +/- 30/66 +/- 18 mm Hg (P water drinking, compared with 22 +/- 10/12 +/- 5 mm Hg with drinking (P water drinking attenuated orthostatic tachycardia (123 +/- 23 beats per minute) at baseline to 108 +/- 21 beats per minute after water drinking ( P Water drinking elicits a rapid pressor response in patients with autonomic failure and can be used to treat orthostatic and postprandial hypotension. Water drinking moderately reduces orthostatic tachycardia in patients with idiopathic orthostatic intolerance. Thus, water drinking may serve as an adjunctive treatment in patients with impaired orthostatic tolerance.

  3. Validation Aspects of Water Treatment Systems for Pharmaceutical ...

    African Journals Online (AJOL)

    Erah

    compatible with frequent sanitisation, thermal cycling and must be specified ... Suitable insulation is required to store the water at high ... accessible [11,12]. Valves. Commonly used valves in water treatment systems are gate, ball, butterfly and diaphragm types. For the removal of dissolved solids, diaphragm valves should.

  4. Characterisation of some South African water treatment residues ...

    African Journals Online (AJOL)

    Land application of water treatment residue (WTR) the by-product from the production of potable water, is becoming the preferred method of disposal, as there are environmental concerns and increasingly high costs associated with other disposal options. However, before WTR can be applied to land, consideration needs ...

  5. Benchmarking in the Dutch waste-water treatment sector

    NARCIS (Netherlands)

    Admiraal, R.J.; van Helden, G.J.

    The Dutch water boards have recently completed a performance measurement and evaluation project for waste-water treatment. This Project was intended to strengthen the boards' accountability to their stakeholders and to identify starting Points for Performance improvement. The Balanced Scorecard was

  6. Effectiveness of home water treatment methods in Dschang ...

    African Journals Online (AJOL)

    The MPN (Most Probable Number) technique was used to assess the bacteriological quality of nine of the important drinking water sources in Dschang. Water from the most polluted source was then subjected to six home-based treatment methods, commonly used by the population. Boiling for up to thirty minutes was the ...

  7. TAPWAT: Definition structure and applications for modelling drinking water treatment

    NARCIS (Netherlands)

    Versteegh JFM; Gaalen FW van; Rietveld LC; Evers EG; Aldenberg TA; Cleij P; Technische Universiteit Delft; LWD

    2001-01-01

    The 'Tool for the Analysis of the Production of drinking WATer' (TAPWAT) model has been developed for describing drinking-water quality in integral studies in the context of the Environmental Policy Assessment of the RIVM. The model consists of modules that represent individual steps in a treatment

  8. Water quality modelling and optimisation of wastewater treatment ...

    African Journals Online (AJOL)

    Instream water quality management encompasses field monitoring and utilisation of mathematical models. These models can be coupled with optimisation techniques to determine more efficient water quality management alternatives. Among these activities, wastewater treatment plays a crucial role. In this work, a ...

  9. Review on Chemical treatment of Industrial Waste Water * OPSAHU

    African Journals Online (AJOL)

    MICHAEL HORSFALL

    ABSTRACT: Industrialization played an important role for scio-economy of the country. Generally, a lot of water is used and lot of wastewater generated from industries due their processes and washing purpose. A large number of chemicals are used for the production of potable water and in the treatment of wastewater ...

  10. Effects of forest cover on drinking water treatment costs

    Science.gov (United States)

    Travis Warziniack; Chi Ho Sham; Robert Morgan; Yasha Feferholtz

    2016-01-01

    This paper explores the relationship between forest cover and drinking water treatment costs using results from a 2014 survey by the American Water Works Association (AWWA) that targeted utilities in forested ecoregions in the United States. On the basis of the data collected, there is a negative relationship between forest cover and turbidity, i.e. as forest...

  11. tannery wastes water treatment using moringa stenopetala seed ...

    African Journals Online (AJOL)

    PROF EKWUEME

    processes are available for the adsorption of heavy metals ... temperatures are limiting factor for the cultivation of the species (Orwa et al., 2009).The water soluble Moringa seed proteins possess coagulating properties. .... TANNERY WASTES WATER TREATMENT USING MORINGA STENOPETALA SEED EXTRACT 31 ...

  12. Review on Chemical treatment of Industrial Waste Water | Sahu ...

    African Journals Online (AJOL)

    In potable water treatment chemicals such as inorganic salts and polymeric organic coagulants are used for primary coagulation, as coagulant aids and for sludge dewatering; lime and soda ash allowed for pH correction and water stabilization; caustic soda is used for pH adjustment, powdered activated carbon (PAC) can ...

  13. Validation Aspects of Water Treatment Systems for Pharmaceutical ...

    African Journals Online (AJOL)

    The goal of conducting validation is to demonstrate that a process, when operated within established limits, produces a product of consistent and specified quality with a high degree of assurance. Validation of water treatment systems is necessary to obtain water with all desired quality attributes. This also provides a ...

  14. Comparative study of household water treatment in a rural ...

    African Journals Online (AJOL)

    Comparative study of household water treatment in a rural community in Kwara state, Nigeria. ... Nigerian Journal of Technology ... The physicochemical parameters of the raw water samples with exception of chloride, BOD and dissolved oxygen were within the permissible limits of the World Health Organization (WHO) and ...

  15. The distribution of inherent phosphorus in fifteen water treatment ...

    African Journals Online (AJOL)

    Water treatment residues (WTR), the by-products of the production of potable water, are chemically benign, inorganic materials which are suitable for disposal by land application, though they are frequently reported to have high phosphorus (P) sorption capacities. An understanding of the distribution of inherent P in WTR is, ...

  16. Short communication: Effect of water treatment of sorghum on the ...

    African Journals Online (AJOL)

    The present study was conducted to observe the efficacy of water treatment on sorghum grain and to determine its optimum inclusion in broiler diets. Sorghum grain was treated with water and dried. Seven isoenergetic and isonitrogenous diets were prepared, using raw and treated sorghum, and designated diets A, B, C, D, ...

  17. A comparative life cycle assessment of process water treatment ...

    African Journals Online (AJOL)

    2011-07-29

    Jul 29, 2011 ... softening and hot lime softening. Hot lime softening (HLS) ... filtration. Raw water. Condensate make up to boilers. Condensate. Make Up. Tank. Brines and Sludge management. Treatment chemicals. Electricity. Emmissions ... Feed water is dosed at 5 mg/ℓ with chlorine gas (0.15 kg/Mℓ. BFW), and sodium ...

  18. Hydraulic modelling of drinking water treatment plant operations

    Directory of Open Access Journals (Sweden)

    L. C. Rietveld

    2009-06-01

    Full Text Available The flow through a unit of a drinking water treatment plant is one of the most important parameters in terms of a unit's effectiveness. In the present paper, a new EPAnet library is presented with the typical hydraulic elements for drinking water treatment processes well abstraction, rapid sand filtration and cascade and tower aeration. Using this treatment step library, a hydraulic model was set up, calibrated and validated for the drinking water treatment plant Harderbroek. With the actual valve position and pump speeds, the flows were calculated through the several treatment steps. A case shows the use of the model to calculate the new setpoints for the current frequency converters of the effluent pumps during a filter backwash.

  19. Interaction of inorganic anions with iron-mineral adsorbents in aqueous media--a review.

    Science.gov (United States)

    Kumar, Eva; Bhatnagar, Amit; Hogland, William; Marques, Marcia; Sillanpää, Mika

    2014-01-01

    A number of inorganic anions (e.g., nitrate, fluoride, bromate, phosphate, and perchlorate) have been reported in alarming concentrations in numerous drinking water sources around the world. Their presence even in very low concentrations may cause serious environmental and health related problems. Due to the presence and significance of iron minerals in the natural aquatic environment and increasing application of iron in water treatment, the knowledge of the structure of iron and iron minerals and their interactions with aquatic pollutants, especially inorganic anions in water are of great importance. Iron minerals have been known since long as potential adsorbents for the removal of inorganic anions from aqueous phase. The chemistry of iron and iron minerals reactions in water is complex. The adsorption ability of iron and iron minerals towards inorganic anions is influenced by several factors such as, surface characteristics of the adsorbent (surface area, density, pore volume, porosity, pore size distribution, pHpzc, purity), pH of the solution, and ionic strength. Furthermore, the physico-chemical properties of inorganic anions (pore size, ionic radius, bulk diffusion coefficient) also significantly influence the adsorption process. The aim of this paper is to provide an overview of the properties of iron and iron minerals and their reactivity with some important inorganic anionic contaminants present in water. It also summarizes the usage of iron and iron minerals in water treatment technology. © 2013.

  20. Water-wettable polypropylene fibers by facile surface treatment based on soy proteins.

    Science.gov (United States)

    Salas, Carlos; Genzer, Jan; Lucia, Lucian A; Hubbe, Martin A; Rojas, Orlando J

    2013-07-24

    Modification of the wetting behavior of hydrophobic surfaces is essential in a variety of materials, including textiles and membranes that require control of fluid interactions, adhesion, transport processes, sensing, etc. This investigation examines the enhancement of wettability of an important class of textile materials, viz., polypropylene (PP) fibers, by surface adsorption of different proteins from soybeans, including soy flour, isolate,glycinin, and β-conglycinin. Detailed investigations of soy adsorption from aqueous solution (pH 7.4, 25 °C) on polypropylene thin films is carried out using quartz crystal microbalance (QCM) and surface plasmon resonance (SPR). A significant amount of protein adsorbs onto the PP surfaces primarily due to hydrophobic interactions. We establish that adsorption of a cationic surfactant, dioctadecyldimethylammonium bromide (DODA) onto PP surfaces prior to the protein deposition dramatically enhances its adsorption. The adsorption of proteins from native (PBS buffer, pH 7.4, 25 °C) and denatured conditions (PBS buffer, pH 7.4, 95 °C) onto DODA-treated PP leads to a high coverage of the proteins on the PP surface as confirmed by a significant improvement in water wettability. A shift in the contact angle from 128° to completely wettable surfaces (≈0°) is observed and confirmed by imaging experiments conducted with fluorescence tags. Furthermore, the results from wicking tests indicate that hydrophobic PP nonwovens absorb a significant amount of water after protein treatment, i.e., the PP-modified surfaces become completely hydrophilic.

  1. Use of drinking water treatment solids for arsenate removal from desalination concentrate.

    Science.gov (United States)

    Xu, Xuesong; Lin, Lu; Papelis, Charalambos; Myint, Maung; Cath, Tzahi Y; Xu, Pei

    2015-05-01

    Desalination of impaired water can be hindered by the limited options for concentrate disposal. Selective removal of specific contaminants using inexpensive adsorbents is an attractive option to address the challenges of concentrate management. In this study, two types of ferric-based drinking water treatment solids (DWTS) were examined for arsenate removal from reverse osmosis concentrate during continuous-flow once-through column experiments. Arsenate sorption was investigated under different operating conditions including pH, arsenate concentration, hydraulic retention time, loading rate, temperature, and moisture content of the DWTS. Arsenate removal by the DWTS was affected primarily by surface complexation, electrostatic interactions, and arsenate speciation. Results indicated that arsenate sorption was highly dependent on initial pH and initial arsenate concentration. Acidic conditions enhanced arsenate sorption as a result of weaker electrostatic repulsion between predominantly monovalent H2AsO4(-) and negatively charged particles in the DWTS. High initial arsenate concentration increased the driving force for arsenate sorption to the DWTS surface. Tests revealed that the potential risks associated with the use of DWTS include the leaching of organic contaminants and ammonia, which can be alleviated by using wet DWTS or discarding the initially treated effluent that contains high organic concentration. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Evaluation of a Novel Water Treatment Residual Nanoparticles as a Sorbent for Arsenic Removal

    Directory of Open Access Journals (Sweden)

    Elsayed Elkhatib

    2015-01-01

    Full Text Available A novel sorbent, water treatment residual nanoparticles (nWTR, was synthesized and used to remove As(V from water solutions. The kinetics and equilibrium of As(V adsorption by nWTR were evaluated. The kinetic data for nWTR at 3 different pH values indicate that As(V sorption is biphasic, is favored at low pH values, and followed the power function and first-order kinetics models fit. The results of the batch adsorption study showed that nWTR was effective in As(V removal and its removal capability was 16 times higher than that of bulk WTR. Fourier transmission infrared (FTIR, SEM-EDX spectra, and As fractionation results indicate the crucial role of surface hydroxyl groups in As retention onto nWTR and the high capability of nWTR to immobilize As(V. The stability of As-nWTR surface complexes is suggested as less than 2% of adsorbed As(V was released from nWTR after 4 consecutive desorption cycles.

  3. ETV REPORT: REMOVAL OF ARSENIC IN DRINKING WATER ORCA WATER TECHNOLOGIES KEMLOOP 1000 COAGULATION AND FILTRATION WATER TREATMENT SYSTEM

    Science.gov (United States)

    Verification testing of the ORCA Water Technologies KemLoop 1000 Coagulation and Filtration Water Treatment System for arsenic removal was conducted at the St. Louis Center located in Washtenaw County, Michigan, from March 23 through April 6, 2005. The source water was groundwate...

  4. Environmental-benign utilisation of fly ash as low-cost adsorbents.

    Science.gov (United States)

    Wang, Shaobin; Wu, Hongwei

    2006-08-25

    Fly ash is a waste substance from thermal power plants, steel mills, etc. that is found in abundance in the world. In recent years, utilisation of fly ash has gained much attention in public and industry, which will help reduce the environmental burden and enhance economic benefit. In this paper, the technical feasibility of utilisation of fly ash as a low-cost adsorbent for various adsorption processes for removal of pollutants in air and water systems has been reviewed. Instead of using commercial activated carbon or zeolites, a lot of researches have been conducted using fly ash for adsorption of NO(x), SO(x), organic compounds, and mercury in air, and cations, anions, dyes and other organic matters in waters. It is recognised that fly ash is a promising adsorbent for removal of various pollutants. Chemical treatment of fly ash will make conversion of fly ash into a more efficient adsorbent for gas and water cleaning. Investigations also revealed that unburned carbon component in fly ash plays an important role in adsorption capacity. Directions for future research are also discussed.

  5. Computer simulations of adsorbed liquid crystal films

    Science.gov (United States)

    Wall, Greg D.; Cleaver, Douglas J.

    2003-01-01

    The structures adopted by adsorbed thin films of Gay-Berne particles in the presence of a coexisting vapour phase are investigated by molecular dynamics simulation. The films are adsorbed at a flat substrate which favours planar anchoring, whereas the nematic-vapour interface favours normal alignment. On cooling, a system with a high molecule-substrate interaction strength exhibits substrate-induced planar orientational ordering and considerable stratification is observed in the density profiles. In contrast, a system with weak molecule-substrate coupling adopts a director orientation orthogonal to the substrate plane, owing to the increased influence of the nematic-vapour interface. There are significant differences between the structures adopted at the two interfaces, in contrast with the predictions of density functional treatments of such systems.

  6. Melamine-based dendrimer amine-modified magnetic nanoparticles as an efficient Pb(II) adsorbent for wastewater treatment: Adsorption optimization by response surface methodology.

    Science.gov (United States)

    Jiryaei Sharahi, Fatemeh; Shahbazi, Afsaneh

    2017-12-01

    Magnetic Fe 3 O 4 nanoparticles with an average diameter of 64 nm was synthesized solvothermically and subsequently modified with melamine-based dendrimer amine (MDA-Fe 3 O 4 ) via grafting method. The synthesized materials were characterized using DLS, SEM, XRD, FTIR, VSM, TGA and elemental analysis techniques. The MDA-Fe 3 O 4 was employed for the efficient removal of Pb(II) ions from an aqueous solution. The adsorption efficiency was investigated in relation to the independent variables of Pb(II) concentration (80-250 mg L -1 ), pH of the solution (3-7), adsorbent dosage (0.1-0.5 g L -1 ) and temperature (10-40 °C) via a central composite design (CCD) using response surface methodology (RSM). The significance of independent variables and their interactions was tested using ANOVA at a 95% confidence limit (α = 0.05). A second-order quadratic model was established to predict the adsorption efficiency. Under the optimum condition (initial Pb(II) concentration = 110 mg L -1 , MDA-Fe 3 O 4 dosage = 0.49 g L -1 , pH = 5 and temperature = 30 °C) a removal percentage of 85.6% was obtained. The isotherm data fitted well to the Freundlich model within the concentration range of the experimental study. A maximum adsorption capacity of 333.3 mg g -1 was predicted by the Langmuir model. The adsorption rate of Pb(II) ions onto MDA-Fe 3 O 4 was in good agreement with the pseudo-second-order model (R 2  = 0.999; k 2  = 4.7 × 10 -4  g mg -1 min -1 ). Thermodynamically, adsorption was spontaneous and endothermic. The MDA-Fe 3 O 4 was successfully regenerated using 0.3 M HCl with little loss of adsorption capacity (≈7%) for five successive adsorption cycles. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Using bamboo charcoal as solid-phase extraction adsorbent for the ultratrace-level determination of perfluorooctanoic acid in water samples by high-performance liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Zhao, Ru-Song; Wang, Xia; Wang, Xu; Lin, Jin-Ming; Yuan, Jin-Peng; Chen, Li-Zong

    2008-03-01

    In recent years, bamboo charcoal, a new kind of material with special microporous and biological characteristics, has attracted great attention in many application fields. In this paper, the potential of bamboo charcoal to act as a solid-phase extraction (SPE) adsorbent for the enrichment of the environmental pollutant perfluorooctanoic acid, which is one of the newest types of persistent organic pollutants in the environment, has been investigated. Important factors that may influence the enrichment efficiency--such as the eluent and its volume, the flow rate of the sample, the pH of the sample and the sample volume--were investigated and optimized in detail. Under the optimum conditions, the limit of detection for PFOA was 0.2 ng L(-1). The experimental results indicated that this approach gives good linearity (R(2) = 0.9995) over the range 1-1000 ng L(-1) and good reproducibility, with a relative standard deviation of 4.0% (n = 5). The proposed method has been applied to the analysis of real water samples, and satisfactory results were obtained. The average spiked recoveries were in the range 79.5-118.3%. All of the results indicate that the proposed method could be used for the determination of PFOA at ultratrace levels in water samples.

  8. Application of bamboo charcoal as solid-phase extraction adsorbent for the determination of atrazine and simazine in environmental water samples by high-performance liquid chromatography-ultraviolet detector.

    Science.gov (United States)

    Zhao, Ru-Song; Yuan, Jin-Peng; Jiang, Ting; Shi, Jun-Bo; Cheng, Chuan-Ge

    2008-08-15

    In this article, a new method for the determination of triazine herbicides atrazine and simazine in environment aqueous samples was developed. It was based on solid-phase extraction (SPE) using bamboo charcoal as adsorbent and high-performance liquid chromatography-ultraviolet detector (HPLC-UV) for the enrichment and determination of atrazine and simazine at trace level. Related important factors influencing the extraction efficiency, such as the kind of eluent and its volume, flow rate of the sample, pH of the sample, and volume of the sample, were investigated and optimized in detail. Under the optimal conditions, the experimental results showed that excellent linearity was obtained over the range of 0.5-30 microg L(-1) with correlation coefficients 0.9991 and 0.9982, for atrazine and simazine, respectively; and the relative standard deviations of two analytes were 8.3, 8.7%, respectively. The proposed method was successfully applied to the analysis of tap water and well water samples. And satisfactory spiked recoveries were obtained in the range of 75.2-107.1%. The above results indicated that the developed method was an excellent alternative for the routine analysis in environmental field.

  9. Factors influencing biological treatment of MTBE contaminated ground water

    Energy Technology Data Exchange (ETDEWEB)

    Stringfellow, William T.; Hines Jr., Robert D.; Cockrum, Dirk K.; Kilkenny, Scott T.

    2001-09-14

    Methyl tert-butyl ether (MTBE) contamination has complicated the remediation of gasoline contaminated sites. Many sites are using biological processes for ground water treatment and would like to apply the same technology to MTBE. However, the efficiency and reliability of MTBE biological treatment is not well documented. The objective of this study was to examine the operational and environmental variables influencing MTBE biotreatment. A fluidized bed reactor was installed at a fuel transfer station and used to treat ground water contaminated with MTBE and gasoline hydrocarbons. A complete set of chemical and operational data was collected during this study and a statistical approach was used to determine what variables were influencing MTBE treatment efficiency. It was found that MTBE treatment was more sensitive to up-set than gasoline hydrocarbon treatment. Events, such as excess iron accumulation, inhibited MTBE treatment, but not hydrocarbon treatment. Multiple regression analysis identified biomass accumulation and temperature as the most important variables controlling the efficiency of MTBE treatment. The influent concentration and loading of hydrocarbons, but not MTBE, also impacted MTBE treatment efficiency. The results of this study suggest guidelines for improving MTBE treatment. Long cell retention times in the reactor are necessary for maintaining MTBE treatment. The onset of nitrification only occurs when long cell retention times have been reached and can be used as an indicator in fixed film reactors that conditions favorable to MTBE treatment exist. Conversely, if the reactor can not nitrify, it is unlikely to have stable MTBE treatment.

  10. Pollution Impact and Alternative Treatment for Produced Water

    Directory of Open Access Journals (Sweden)

    Hedar Yusran

    2018-01-01

    Full Text Available Oil and gas exploration and production are two of the activities that potentially cause pollution and environmental damage. The largest waste generated from this activity is produced water. Produced water contains hazardous pollutants of both organic and inorganic materials, so that the produced water of oil and gas production cannot be discharged directly to the environment. Uncontrolled discharge can lead to the environmental damage, killing the life of water and plants. The produced water needs to be handled and fulfill the quality standards before being discharged to the environment. Several studies to reduce the contaminants in the produced water were conducted by researchers. Among them were gravity based separation - flotation, separation technique based on filtration, and biological process treatment. Therefore, some of these methods can be used as an alternative waste handling of produced water.

  11. Hygiena 3, a Forgotten Project for Electrolytic Water Treatment

    Directory of Open Access Journals (Sweden)

    Kryštof Drnek

    2012-01-01

    Full Text Available In the interwar period, the city of Prague had to resolve the problem of treating the polluted water produced by its citizens. From 1933 - 1936 an ambitious competition was held. The idea behind the competition was to bring in new ideas and projects for a new water treatment station.Hygiena 3 was one of the projects that was submitted. It proposed a treatment procedure based on electrolytic consolidation of contaminants in water into flocks. The project was found to be inventive and interesting but too expensive and not effective. Nevertheless it was evaluated as a well developed proposal and received an award from the city.

  12. Techniques of WasteWater Treatment-Introduction to Effluent ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 11. Techniques of WasteWater Treatment - Introduction to Effluent Treatment and Industrial Methods. Amol A Kulkarni Mugdha Deshpande A B Pandit. General Article Volume 5 Issue 11 November 2000 pp 56-68 ...

  13. Biological black water treatment combined with membrane separation

    NARCIS (Netherlands)

    Voorthuizen, van E.M.; Zwijnenburg, A.; Meer, van der W.; Temmink, H.

    2008-01-01

    Separate treatment of black (toilet) water offers the possibility to recover energy and nutrients. In this study three combinations of biological treatment and membrane filtration were compared for their biological and membrane performance and nutrient conservation: a UASB followed by effluent

  14. Modelling of a Small Scale Waste Water Treatment Plant (SSWWTP ...

    African Journals Online (AJOL)

    One of the most important environmental problems faced by the world today is waste handling and due to variation in waste water with respect to homes. The two main treatment used here are the aerobic and the anaerobic treatment process. The processes are brought to increase the efficiency of the plant. The plant has ...

  15. An Update on Modifications to Water Treatment Plant Model

    Science.gov (United States)

    Water treatment plant (WTP) model is an EPA tool for informing regulatory options. WTP has a few versions: 1). WTP2.2 can help in regulatory analysis. An updated version (WTP3.0) will allow plant-specific analysis (WTP-ccam) and thus help meet plant-specific treatment objectives...

  16. Effects of Hot Water Treatment and Temperature on Seedling ...

    African Journals Online (AJOL)

    An experiment was conducted at the Faculty of Agriculture, University of Maiduguri, to study the effect of hot water treatment and temperature on the morphological characteristics of Arabic gum. The experiment was laid out in a Randomized Complete Block Design in a factorial arrangement. The treatments included a ...

  17. Modelling of a Small Scale Waste Water Treatment Plant (SSWWTP)

    African Journals Online (AJOL)

    PROF. OLIVER OSUAGWA

    2014-06-01

    Jun 1, 2014 ... Abstract. One of the most important environmental problems faced by the world today is waste handling and management, due to variation in waste water with respect to homes. The two main treatment methods used here are the aerobic and the anaerobic treatment process. The processes are brought.

  18. COST ESTIMATION MODELS FOR DRINKING WATER TREATMENT UNIT PROCESSES

    Science.gov (United States)

    Cost models for unit processes typically utilized in a conventional water treatment plant and in package treatment plant technology are compiled in this paper. The cost curves are represented as a function of specified design parameters and are categorized into four major catego...

  19. A Zn2GeO4-ethylenediamine hybrid nanoribbon membrane as a recyclable adsorbent for the highly efficient removal of heavy metals from contaminated water.

    Science.gov (United States)

    Yu, Li; Zou, Rujia; Zhang, Zhenyu; Song, Guosheng; Chen, Zhigang; Yang, Jianmao; Hu, Junqing

    2011-10-14

    Zn(2)GeO(4)-ethylenediamine (ZGO-EDA) hybrid nanoribbons have been synthesized on a large-scale and directly assembled to membranes, which exhibit an excellent recyclability, high selectivity, and good thermal stability for highly efficient removal of heavy metal ions, i.e., Pb(2+), Cd(2+), Co(2+), and Cu(2+), from contaminated water. This journal is © The Royal Society of Chemistry 2011

  20. Use of Fe/Al drinking water treatment residuals as amendments for enhancing the retention capacity of glyphosate in agricultural soils.

    Science.gov (United States)

    Zhao, Yuanyuan; Wendling, Laura A; Wang, Changhui; Pei, Yuansheng

    2015-08-01

    Fe/Al drinking water treatment residuals (WTRs), ubiquitous and non-hazardous by-products of drinking water purification, are cost-effective adsorbents for glyphosate. Given that repeated glyphosate applications could significantly decrease glyphosate retention by soils and that the adsorbed glyphosate is potentially mobile, high sorption capacity and stability of glyphosate in agricultural soils are needed to prevent pollution of water by glyphosate. Therefore, we investigated the feasibility of reusing Fe/Al WTR as a soil amendment to enhance the retention capacity of glyphosate in two agricultural soils. The results of batch experiments showed that the Fe/Al WTR amendment significantly enhanced the glyphosate sorption capacity of both soils (pglyphosate desorbed from the non-amended soils, and the Fe/Al WTR amendment effectively decreased the proportion of glyphosate desorbed. Fractionation analyses further demonstrated that glyphosate adsorbed to non-amended soils was primarily retained in the readily labile fraction (NaHCO3-glyphosate). The WTR amendment significantly increased the relative proportion of the moderately labile fraction (HCl-glyphosate) and concomitantly reduced that of the NaHCO3-glyphosate, hence reducing the potential for the release of soil-adsorbed glyphosate into the aqueous phase. Furthermore, Fe/Al WTR amendment minimized the inhibitory effect of increasing solution pH on glyphosate sorption by soils and mitigated the effects of increasing solution ionic strength. The present results indicate that Fe/Al WTR is suitable for use as a soil amendment to prevent glyphosate pollution of aquatic ecosystems by enhancing the glyphosate retention capacity in soils. Copyright © 2015. Published by Elsevier B.V.