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Öğe Amberlite IRA-400 and IRA-743 chelating resins for the sorption and recovery of molybdenum(VI) and vanadium(V): Equilibrium and kinetic studies(Elsevier Science Bv, 2017) Polowczyk, Izabela; Cyganowski, Piotr; Urbano, Bruno F.; Rivas, Bernabe L.; Bryjak, Marek; Kabay, NalanIn this study, commercial polymers containing N-methyl-D-glucamine-quaternary ammonium ion-exchange ligands were subjected to a series of sorption tests. Mo(VI) and V(V) sorption were performed using strong (Amberlite IRA-400) and weak (Amberlite IRA-743) ion-exchange resins as adsorbents under equilibrium and kinetic conditions. The tests involved evaluating the influence of the adsorbent dose, pH, and temperature. The adsorbed Mo(VI) and V(V) levels reached maximum values at fixed pHs of 6.0 and 4.0 for IRA-400 and IRA-743, respectively. The maximum Mo(VI) and V(V) batch uptakes were determined to be 208 and 177 mg.g(-1) for IRA-743 and IRA-400, respectively. The increase in temperature resulted in increasing Mo(VI) and V(V) sorption capacities for both resins, indicating the endothermic nature of the process. The most rapid adsorption equilibrium was achieved after 30 min during sorption of Mo(VI) on the IRA-400 resin, which resulted in the removal of nearly all metal from the solution. Molybdenum and vanadium adsorption/desorption cycles were performed to estimate the adsorbent lifetime, and good efficiency was observed during three cycles of elution and reuse. FTIR analysis confirmed the presence of Mo and V species within the structures of the IRA-400 and IRA-743 resins after the sorption process. (C) 2017 Elsevier B.V. All rights reserved.Öğe ARSENIC SORPTION USING MIXTURES OF ION EXCHANGE RESINS CONTAINING N-METHYL-D-GLUCAMINE AND QUATERNARY AMMONIUM GROUPS(Soc Chilena Quimica, 2016) Ozkula, Gulsah; Urbano, Bruno F.; Rivas, Bernabe L.; Kabay, Nalan; Bryjak, MarekThe method of synthesis and the arsenic removal properties of ion-exchange resins based on N-methyl-D-glucamine and trimethylammonium groups are presented. The N-methyl-D-glucamine based monomer was synthesized by the reaction of 4-vinyl benzyl chloride with N-methyl-D-glucamine, along with the use of N, N-methylene-bis-acrylamide as a crosslinker reagent for polymerization. In addition, poly(4-vinylbenzyl) trimethylammonium was synthesized. Arsenate sorption studies were conducted and the pH effect, kinetics, sorption capacity, and elution performance were studied. The experimental data were fitted to kinetic models, such as the pseudo-first order and pseudo-second order models. The pseudo-second order model exhibited the best correlation with the experimental data. The Langmuir and Freundlich isotherms were fitted to the experimental data, and the Freundlich isotherm exhibited the best fit.Öğe Boron removal by liquid-phase polymer-based retention technique using poly(glycidyl methacrylate N-methyl D-glucamine)(Wiley-Blackwell, 2013) Sanchez, Julio; Rivas, Bernabe L.; Nazar, Eliza; Bryjak, Marek; Kabay, NalanThe removal of boron was analyzed by liquid-phase polymer based retention (LPR) technique using washing and enrichment method. The extracting reagents were water-soluble polymers (WSPs) containing quaternary ammonium salts and N-methyl-D-glucamine (NMG) groups. The removal experiments of boron using the washing method were conducted at 1 bar of pressure by varying pH, polymer:boron molar ratio, and concentrations of interfering ions (chloride and sulfate). The results showed higher retention capacity for boron (60%) at pH 10 with the polymer containing NMG group. The optimal polymer:boron molar ratio was 40 : 1. Selectivity experiments showed that the presence of interfering ions did not affect the boron removal capacity. The maximal boron retention capacity was determined by the enrichment method, obtaining a value of 12 mg B/g-polymer. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013Öğe A comparative study of removal of Cr(VI) by ion exchange resins bearing quaternary ammonium groups(Wiley, 2014) Kusku, Ozge; Rivas, Bernabe L.; Urbano, Bruno F.; Arda, Muserref; Kabay, Nalan; Bryjak, MarekBACKGROUNDIon exchange resins based on poly[(4-vinylbenzyl) trimethylammonium chloride] P(ClVBTA) and poly[(3-acrylamidopropyl) trimethyl ammonium chloride] P(ClAPTA) were synthesized by radical polymerization. Metal ion uptake experiments were run with these synthesized resins and compared with the commercially available anion exchange resin Amberlite IRA-400. RESULTSRetention of Cr(VI) was found to be independent of pH and the co-existence of Cl- and SO42- ions for two resins. The sorption data obtained were evaluated using well-known kinetic and adsorption isotherm models. The kinetic data obtained for the two resins fitted well to the pseudo-second-order model and the Langmuir isotherm. Besides, it was observed that temperature influenced slightly the sorption properties of the ion exchange resins synthesized in this study and commercially available ion exchange resin Amberlite IRA-400. CONCLUSIONSThe synthetic resins showed a better sorption performance than a commercially available ion exchange resin. The P(ClVBTA) and P(ClAPTA) resins exhibited greater and faster sorption than Amberlite IRA-400. Sorption capacities of these ion exchangers were found to be in the order P(ClAPTA)>P(ClVBTA)>Amberlite IRA-400. (c) 2014 Society of Chemical Industry.Öğe Cr(III) REMOVAL FROM AQUEOUS SOLUTION BYION EXCHANGE RESINS CONTAINING CARBOXYLIC ACID AND SULPHONIC ACID GROUPS(Soc Chilena Quimica, 2018) Rivas, Bernabe L.; Morales, Daniela V.; Kabay, Nalan; Bryjak, MarekIon exchange resins based on the water-insoluble polymers poly(acrylamide-co-styrene sodium sulfonate) (P(AAm-co-ESS)), poly(2-acrylamide-2-methyl-1-propanesulfonic acid-co-acrylicacid) (P(APSA-co-AAc)), poly(2-acrylamidoglycolic acid-co-2-acrylamide-2-methyl-1-propane sulfonic acid) (P(AAGA-co-APSA)), and poly(2-acrylamidoglycolic acid-co-4-styrene sodium sulfonate) (P(AAGA-co-ESS)) were synthesized by radical polymerization. These polymers were employed to remove Cr(III) from an aqueous solution. The optimum sorption parameters of amount of resin and sorption time were obtained through batch-mode sorption tests. Following batch elution tests to identify the best eluting agent. Finally, the column-mode sorption/elution behaviors of ion exchange resins were studied. The ion exchange resins exhibited excellent removal of Cr(III). The P(AAGA-co-APSA) resin exhibited 89.4% removal, while P(AAGA-co-ESS) displayed 88.3%, P(AAm-co-ESS) 86.8%, and P(APSA-co-AAc) 89.3%. The column-mode was studied by the P(AAGA-co-APSA) resingave a breakthrough capacity of 1.5 mg Cr(III)/mL resin in the first cycle. The elution efficiency was almost 100%. The breakthrough capacity was 1.2 mg Cr(III)/mL resin in the second cycle. The elution efficiency was 90.2% in the second cycle.Öğe Equilibrium and kinetic study of chromium sorption on resins with quaternary ammonium and N-methyl-D-glucamine groups(Elsevier Science Sa, 2016) Polowczyk, Izabela; Urbano, Bruno F.; Rivas, Bernabe L.; Bryjak, Marek; Kabay, NalanThe equilibrium and kinetics of chromium (VI) adsorption on a new synthesized resin containing both N-methyl-D-glucamine and quaternary ammonium functional groups P(VbNMDG-co-ClVBTA) have been presented. The results obtained for the new copolymer were compared with those for two commercial resins, namely Amberlite IRA-743 and IRA-400, containing only N-methyl-D-glucamine and quaternary ammonium functional groups, respectively. The effect of adsorbent dose, pH, temperature, and interfering ions on chromium removal was studied. The maximum chromium uptake for the copolymer was 677.9 mg g(resin)(-1) at pH 4-5, while those for IRA-400 and IRA-743 were 893.4 and 316.6 mg g(resin)(-1), respectively. Chloride and sulfate anions did not exhibit an effect on chromium sorption for the copolymer and IRA-400; however, sorption on the IRA-743 resin was affected. The adsorption kinetics and isotherms as well as thermodynamic parameters were evaluated. Increasing temperature decreased the chromium adsorption for both commercial and synthesized resins, revealing the exothermic nature of the process. The Freundlich and Langmuir isotherm models were used to describe the adsorption of Cr(VI) onto resins. Kinetic studies revealed that Cr(VI) reached over 99% removal at 10, 30, and 240 min for the copolymer, IRA-400, and IRA-743, respectively. Chromium adsorption/desorption cycles were performed to estimate the adsorbent lifetime, where the copolymer resin exhibited a better performance than IRA-400, and IRA-743, achieving a high efficiency after 3 cycles. (C) 2015 Elsevier B.V. All rights reserved.Öğe Polypropylene membranes modified with interpenetrating polymer networks for the removal of chromium ions(Wiley, 2015) Tapiero, Yesid; Rivas, Bernabe L.; Sanchez, Julio; Bryjak, Marek; Kabay, NalanPolypropylene (PP) membranes incorporating poly[(ar-vinylbenzyl) trimethylammonium chloride] P(ClVBTA), and poly[sodium (styrene sulfonate)] P(SSNa) were modified via an in situ radical polymerization synthesis. Two methods were used for impregnation of the reactive solution: pressure injection and plasma superficial activation with argon gas. The following conditions were varied: the monomer concentrations, number of injections, and cross-linked concentration. The modified polypropylene membranes were then characterized using scanning electron microscopy/energy dispersive X-ray spectroscopy, Fourier transform-infrared spectroscopy, electrokinetic potential, and Donnan dialysis for the chromium ions transport. The modified membranes exhibited a hydrophilic character with a water uptake capacity between 15% and 20% and a percent modification between 2.5% and 4.0%. This was compared with the results of an unmodified polypropylene membrane as the blank and the mentioned polypropylene membrane has not the capacity to uptake water because this kind of material is highly hydrophobic. Hexavalent chromium ions were efficiently transported by the modified membranes containing P(ClVBTA) via a plasma method and it achieved 59.2% extraction at pH 9.0 using a 1-mol L-1 NaCl extraction agent. Therefore, unmodified polypropylene membrane shows an extraction percentage close to 10% from the hexavalent chromium ions at pH 9.0. In the same way, the trivalent chromium transport using membranes modified with P(SSNa) achieved 49.0% extraction at pH 2.0 using 1 x 10(-1) mol L-1 HNO3 and 1 mol L-1 NaCl as the extraction agents. Moreover, the unmodified polypropylene membrane reached a value close to 10% from the trivalent chromium ions using 1 x 10(-1) mol L-1 HNO3 and 1 mol L-1 NaCl. (c) 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41953.Öğe Polypropylene membranes modified with interpenetrating polymer networks for the removal of chromium ions(Wiley, 2015) Tapiero, Yesid; Rivas, Bernabe L.; Sanchez, Julio; Bryjak, Marek; Kabay, NalanPolypropylene (PP) membranes incorporating poly[(ar-vinylbenzyl) trimethylammonium chloride] P(ClVBTA), and poly[sodium (styrene sulfonate)] P(SSNa) were modified via an in situ radical polymerization synthesis. Two methods were used for impregnation of the reactive solution: pressure injection and plasma superficial activation with argon gas. The following conditions were varied: the monomer concentrations, number of injections, and cross-linked concentration. The modified polypropylene membranes were then characterized using scanning electron microscopy/energy dispersive X-ray spectroscopy, Fourier transform-infrared spectroscopy, electrokinetic potential, and Donnan dialysis for the chromium ions transport. The modified membranes exhibited a hydrophilic character with a water uptake capacity between 15% and 20% and a percent modification between 2.5% and 4.0%. This was compared with the results of an unmodified polypropylene membrane as the blank and the mentioned polypropylene membrane has not the capacity to uptake water because this kind of material is highly hydrophobic. Hexavalent chromium ions were efficiently transported by the modified membranes containing P(ClVBTA) via a plasma method and it achieved 59.2% extraction at pH 9.0 using a 1-mol L-1 NaCl extraction agent. Therefore, unmodified polypropylene membrane shows an extraction percentage close to 10% from the hexavalent chromium ions at pH 9.0. In the same way, the trivalent chromium transport using membranes modified with P(SSNa) achieved 49.0% extraction at pH 2.0 using 1 x 10(-1) mol L-1 HNO3 and 1 mol L-1 NaCl as the extraction agents. Moreover, the unmodified polypropylene membrane reached a value close to 10% from the trivalent chromium ions using 1 x 10(-1) mol L-1 HNO3 and 1 mol L-1 NaCl. (c) 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41953.Öğe Polypropylene membranes modified with interpenetrating polymer networks for the removal of chromium ions(Wiley, 2015) Tapiero, Yesid; Rivas, Bernabe L.; Sanchez, Julio; Bryjak, Marek; Kabay, NalanPolypropylene (PP) membranes incorporating poly[(ar-vinylbenzyl) trimethylammonium chloride] P(ClVBTA), and poly[sodium (styrene sulfonate)] P(SSNa) were modified via an in situ radical polymerization synthesis. Two methods were used for impregnation of the reactive solution: pressure injection and plasma superficial activation with argon gas. The following conditions were varied: the monomer concentrations, number of injections, and cross-linked concentration. The modified polypropylene membranes were then characterized using scanning electron microscopy/energy dispersive X-ray spectroscopy, Fourier transform-infrared spectroscopy, electrokinetic potential, and Donnan dialysis for the chromium ions transport. The modified membranes exhibited a hydrophilic character with a water uptake capacity between 15% and 20% and a percent modification between 2.5% and 4.0%. This was compared with the results of an unmodified polypropylene membrane as the blank and the mentioned polypropylene membrane has not the capacity to uptake water because this kind of material is highly hydrophobic. Hexavalent chromium ions were efficiently transported by the modified membranes containing P(ClVBTA) via a plasma method and it achieved 59.2% extraction at pH 9.0 using a 1-mol L-1 NaCl extraction agent. Therefore, unmodified polypropylene membrane shows an extraction percentage close to 10% from the hexavalent chromium ions at pH 9.0. In the same way, the trivalent chromium transport using membranes modified with P(SSNa) achieved 49.0% extraction at pH 2.0 using 1 x 10(-1) mol L-1 HNO3 and 1 mol L-1 NaCl as the extraction agents. Moreover, the unmodified polypropylene membrane reached a value close to 10% from the trivalent chromium ions using 1 x 10(-1) mol L-1 HNO3 and 1 mol L-1 NaCl. (c) 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41953.Öğe Removal of Arsenic from Water by Combination of Electro-Oxidation and Polymer Enhanced Ultrafiltration(Wiley-Blackwell, 2014) Arar, Ozgur; Kabay, Nalan; Sanchez, Julio; Rivas, Bernabe L.; Bryjak, Marek; Pena, CarlosWater-soluble poly[glycidyl methacrylate N-methyl D-glucamine], P(GMA-NMG), was synthesized and purified by ultrafiltration membranes. It was subsequently used for arsenic removal by coupling electro-oxidation (EO) and polymer-enhanced ultrafiltration (PEU) processes. In the EO-PEU combined process, P(GMA-NMG) was first used as supporting electrolyte during the exhaustive electro-oxidation of As(III) to As(V) and then it was used to remove As(V) from aqueous solution through PEU. At first stage, the complete EO of As(III) to As(V) was performed with a platinum reticulated vitreous carbon (RVC)-modified electrode and the advancement of the electrolysis was monitored by analytical electrodes. After the oxidation of As(III) to As(V), the PEU was carried out by washing method using regenerate cellulose membrane and 1 bar of pressure. The effects of supporting electrolytes and pH on EO-PEU combined process were investigated. The best results showed that by using P(GMA-NMG) as supporting electrolyte during the complete electrooxidation of As(III) to As(V) followed by PEU separation, almost 80% of As(V) was removed at pH 10. (C) 2013 American Institute of Chemical Engineers Environ Prog, 33: 918-924, 2014Öğe Removal of As(V) using liquid-phase polymer-based retention (LPR) technique with regenerated cellulose membrane as a filter(Springer, 2013) Sanchez, Julio; Bastrzyk, Anna; Rivas, Bernabe L.; Bryjak, Marek; Kabay, NalanIn this study, regenerated cellulose membrane was used as a filter in liquid-phase polymer-based retention technique. The poly(4-vinyl-1-methylpyridinium bromide), P(BrVMP), was used as extracting reagent of As(V). The role of pH, polymer:As(V) molar ratio, and influence of regenerated cellulose membrane were investigated by washing method. It was observed that the efficient retention was obtained at pH 9 with 20:1 polymer:As molar ratio and it was about 100 % at Z = 10 for P(BrVMP). Experimental data showed that the regenerated cellulose membrane, compared to poly(ethersulfone) membrane, has a capacity to interact with As(V). The maximum retention capacity of P(BrVMP) was determined by enrichment method, and then, using alternately washing and enrichment methods, the charge-discharge process and recovery of P(BrVMP) were performed.Öğe Removal of boron from geothermal water by a novel boron selective resin(Elsevier, 2013) Santander, Paola; Rivas, Bernabe L.; Urbano, Bruno F.; Ipek, Idil Yilmaz; Ozkula, Gulsah; Arda, Muserref; Yuksel, Mithat; Bryjak, Marek; Kozlecki, Tomasz; Kabay, NalanIn this study, a novel chelating resin poly(N-(4-vinylbenzyl)-N-methyl-o-glucamine) (P(VbNMDG)) was synthesized. The sorption performance of this resin was compared with boron selective commercial resin Diaion CRB02 containing N-methyl-n-glucamine (NMDG) groups for boron removal from geothermal water. The P(VbNMDG) resin gave a higher sorption capacity and faster kinetics than that of Diaion CRB02 for boron removal from geothermal water. The kinetic data obtained were evaluated using classical kinetic models and diffusion/reaction models. It was concluded that both P(VbNMDG) and Diaion CRB02 resins obeyed pseudo second order kinetic model. Also, the rate controlling step of boron sorption was particle diffusion for both resins. The breakthrough profile of P(VbNMDG) resin for boron was sharper than that of Diaion CRB02. Thus, the degree of the column utilization of P(VbNMDG) resin was also high. The boron loaded on both resins was eluted using 5% H2SO4 solution with a percentage of around 80%. (C) 2012 Elsevier B.V. All rights reserved.Öğe Removal of boron from geothermal water by a novel boron selective resin(Elsevier, 2013) Santander, Paola; Rivas, Bernabe L.; Urbano, Bruno F.; Ipek, Idil Yilmaz; Ozkula, Gulsah; Arda, Muserref; Yuksel, Mithat; Bryjak, Marek; Kozlecki, Tomasz; Kabay, NalanIn this study, a novel chelating resin poly(N-(4-vinylbenzyl)-N-methyl-o-glucamine) (P(VbNMDG)) was synthesized. The sorption performance of this resin was compared with boron selective commercial resin Diaion CRB02 containing N-methyl-n-glucamine (NMDG) groups for boron removal from geothermal water. The P(VbNMDG) resin gave a higher sorption capacity and faster kinetics than that of Diaion CRB02 for boron removal from geothermal water. The kinetic data obtained were evaluated using classical kinetic models and diffusion/reaction models. It was concluded that both P(VbNMDG) and Diaion CRB02 resins obeyed pseudo second order kinetic model. Also, the rate controlling step of boron sorption was particle diffusion for both resins. The breakthrough profile of P(VbNMDG) resin for boron was sharper than that of Diaion CRB02. Thus, the degree of the column utilization of P(VbNMDG) resin was also high. The boron loaded on both resins was eluted using 5% H2SO4 solution with a percentage of around 80%. (C) 2012 Elsevier B.V. All rights reserved.Öğe Removal of boron from water through soluble polymer based on N-methyl-D-glucamine and regenerated-cellulose membrane(Taylor & Francis Inc, 2016) Sanchez, Julio; Wolska, Joanna; Yorukoglu, Eren; Rivas, Bernabe L.; Bryjak, Marek; Kabay, NalanThis paper presents a systematic study of boron removal from simulated and real aqueous systems in northern Chile by means of polymer-enhanced ultrafiltration. Poly(glycidyl methacrylate-N-methyl-D-glucamine), P(GMA-NMG), was used to form complexes with boron, and a cellulose-regenerated membrane was used as a complex separator. The first tests were performed using two simulated water samples from northern Chile with the same pH and concentrations of boron, arsenic, and chloride. P(GMA-NMG) showed a maximum of 60% boron retention for these artificial waters. Studies of boron enrichment using P(GMA-NMG) with simulated water showed that the soluble polymer reached maximum retention capacity values between 2.0 and 4.0mg of B retained per gram of polymer. SEM images and FTIR spectroscopy confirm the deposition of the polymer on the surface of the membrane after polymer-enhanced ultrafiltration, which explains the permeate flux decay observed in retention experiments. Finally, sorption-desorption tests of boron from real water samples show that it is possible to use the polymer P(GMA-NMG) to remove boron from waters of northern Chile. It is also possible to release the retentate and regenerate the water-soluble polymer.Öğe Removal of Cr(VI) by a chelating resin containing N-methyl-d-glucamine(Springer, 2014) Paola Santander, I.; Rivas, Bernabe L.; Urbano, Bruno; Leiton, Lorena; Ipek, Idil Yilmaz; Yuksel, Mithat; Kabay, Nalan; Bryjak, MarekThe resin poly[N-(4-vinylbenzyl)-N-methyl-d-glucamine] [P(VbNMDG)] was synthesized and its performance for Cr(VI) removal was studied. This resin presented a very fast kinetic of Cr(VI) sorption following a pseudo-second order. Also, the rate-controlling step of Cr(VI) sorption performed by film diffusion in accordance with infinite solution volume model and reacted layer in accordance with unreacted core model. The column study showed a breakthrough capacity of 12.2 mg Cr/mL-resin, with an elution efficiency of 92 %. Mechanism of sorption could correspond to an electrostatic interaction followed by a complexation reaction.Öğe Removal of Cr(VI) from aqueous solution by a highly efficient chelating resin(Springer, 2017) Santander, Paola; Morales, Daniela; Rivas, Bernabe L.; Kabay, Nalan; Yilmaz, Idil; Kusku, Ozge; Yuksel, Mithat; Bryjak, MarekThe poly([(2-methacryloyloxy)ethyl]trimethylammonium chloride) [P(MOTA)] based chelating resin was synthesized by radical polymerization and employed for Cr(VI) removal. The sorption capacity of this resin was very high with a fast sorption rate for Cr(VI) obeying a pseudo-second order kinetic model. In agreement to diffusion model equations, the rate determining step was film diffusion according to the infinite solution volume (ISV) model and reacted layer in accordance with the unreacted core (UC) model. In a column-mode sorption study, the breakthrough capacity obtained was 24.3 mg Cr/mL-resin. The elution of Cr(VI) from the resin was achieved using a mixture of 1.0 mol/L NaOH and 1.0 mol/L NaCl with an elution efficiency of about 100 %. Based on FT-IR measurements, it was clearly understood that Cr(VI) was sorbed by the resin through the quaternary amine functional groups.Öğe Synthetic strong base anion exchange resins: synthesis and sorption of Mo(VI) and V(V)(Springer, 2018) Cyganowski, Piotr; Polowczyk, Izabela; Morales, Daniela V.; Urbano, Bruno F.; Rivas, Bernabe L.; Bryjak, Marek; Kabay, NalanThe result of synthesizing anion exchangers bearing trimethylammonium functionalities is presented. Ion exchange resins of poly(4-vinylbenzyltrimethylammonium chloride) (PVBTAC) (Resin 1) and poly(3-acrylamidopropyltrimethylammonium chloride) (PAPTAC) (Resin 2) were obtained via the radical polymerization technique and studies on the sorption of molybdenum and vanadium ions were conducted at 20, 30, and 40 degrees C using the batch method from single-component aqueous solutions. The greatest total sorption capacities were 198 mg Mo(VI) g(-1) at 20 degrees C and 193 mg V(V) g(-1) at 40 degrees C for Resin 1. The calculated thermodynamic parameters demonstrated that the sorption of Mo(VI) was an exothermic process, while the uptake of V(V) was endothermic. The kinetic studies revealed the compliance of the process with a quasi-second-order kinetic model. Simultaneously, equilibrium was achieved within 15 min in two rate-controlled stages. The fitting of the Langmuir and Freundlich mathematical models demonstrated the chemical character of the sorption processes. Elution and reuse studies showed that Mo(VI) may be completely recovered from both resins using a sodium carbonate solution. Moreover, the investigated materials are suitable for repeated sorption/desorption cycles.Öğe Ultrafiltration assisted by water-soluble poly(diallyl dimethyl ammonium chloride) for As(V) removal(Springer, 2016) Sanchez, Julio; Rivas, Bernabe L.; Ozgoz, Selin; Otles, Semih; Kabay, Nalan; Bryjak, MarekArsenic is a very toxic element that must be removed efficiently from aqueous streams. Among the most promising techniques used for the removal of arsenic are separation methods using membranes. In this study, a regenerated cellulose ultrafiltration (UF) membrane and a poly(diallyl dimethyl ammonium chloride) P(DADMAC) were coupled and used in combination to remove As(V) from an aqueous solution. The influences of pH, the polymer: As(V) molar ratio, and the presence of interfering ions such as chloride and sulfate were investigated in arsenic removal via the washing method. The efficient retention of arsenic was observed at pH 7 with a 5: 1 polymer: As molar ratio and with an efficiency of approximately 85 % at Z = 10 for P(DADMAC). The maximum retention capacity of As(V) was determined by the enrichment method, and the results indicated that 194 mg of As(V) was removed per gram of polymer. Finally, using enrichment and washing methods sequentially, the sorption-desorption process and regeneration of P(DADMAC) were performed successfully.Öğe Water-Insoluble Copolymer Based on N-Methyl-D-glucamine and Quaternary Ammonium Groups with Capability to Remove Arsenic(Wiley-Blackwell, 2014) Urbano, Bruno F.; Paredes, Joel; Rivas, Bernabe L.; Kusku, Ozge; Kabay, Nalan; Bryjak, MarekThe synthesis and sorption performance of As(V) with a copolymer resin is presented. The resin was obtained via the radical polymerization of a 1:1 mixture of N-(4-vinyl benzyl)-N-methyl-D-glucamine and (4-vinyl benzyl)trimethyl ammonium chloride using N,N-methylene-bis-acrylamide as the crosslinker. The effect of pH, concentration, and time on the arsenic sorption was studied. The copolymer exhibited good performance over a wide pH range regardless of the initial concentrations. The equilibrium experiments presented better results under alkaline conditions (pH 9.0) compared with acidic conditions (pH 3.0). The kinetic sorption was quite fast, particularly at low arsenic concentrations. In addition, the arsenic anions were eluted with different acid/alkaline reagents, and the acid eluents exhibited the best results. (c) 2013 American Institute of Chemical Engineers Environ Prog, 33: 1187-1193, 2014Öğe Water-Soluble Polymer and Photocatalysis for Arsenic Removal(Wiley, 2014) Yuksel, Suna; Rivas, Bernabe L.; Sanchez, Julio; Mansilla, Hector D.; Yanez, Jorge; Kochifas, Pia; Kabay, Nalan; Bryjak, MarekIn this study, the photocatalytic oxidation of hazardous arsenite (As(III)) to arsenate (As(V)) and the sequential removal of arsenate from aqueous solution by liquid-phase polymer-based retention (LPR) were investigated. The photocatalytic oxidation of arsenite was performed using TiO2 (P25 Degussa, Germany) under UV-A light. The optimal photocatalytic conditions to oxidize 10 mg L-1 of arsenite solution were achieved using a 0.5 g L-1 of catalyst at a pH value of 2. The As(III) oxidation reached 100% after 30 min of illumination with UV-A light. A water-soluble polymer containing quaternary ammonium groups, poly(3-acrylamidopropyl) trimethylammonium chloride (P(ClAPTA)), was used as an extracting reagent in the LPR process. To obtain the optimized conditions, the removal experiments were performed at various polymer : As(V) molar ratios using 10 mg L-1 of arsenate solutions. After the oxidation of As(III) to As(V), the removal of arsenate by P(ClAPTA) was obtained in a 99% yield using a 20 : 1 polymer : As(V) molar ratio at a pH value of 9. The results demonstrate that the combination of these methods is highly useful for potential applications related to the treatment of wastewater contaminated with As(III). (C) 2014 Wiley Periodicals, Inc.
