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Adil Denizli - One of the best experts on this subject based on the ideXlab platform.
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synthesis and characterization of poly ethylene glycol dimethacrylate 1 vinyl 1 2 4 triazole copolymer beads for heavy Metal Removal
Journal of Applied Polymer Science, 2006Co-Authors: Lokman Uzun, Ali Kara, Necati Besirli, Nalan Tuzmen, Abdulkerim Karabakan, Adil DenizliAbstract:We prepared poly(ethylene glycol dimethacrylate–1-vinyl-1,2,4-triazole) [poly(EGDMA–VTAZ)] beads (average diameter = 150–200 μm) by copolymerizing ethylene glycol dimethacrylate (EGDMA) with 1-vinyl-1,2,4-triazole (VTAZ). The copolymer composition was characterized by elemental analysis and found to contain five EGDMA monomer units for each VTAZ monomer unit. The poly(EGDMA–VTAZ) beads had a specific surface area of 65.8 m2/g. Poly(EGDMA–VTAZ) beads were characterized by Fourier transform infrared spectroscopy, elemental analysis, surface area measurements, swelling studies, and scanning electron microscopy. Poly(EGDMA–VTAZ) beads with a swelling ratio of 84% were used for the heavy-Metal Removal studies. The adsorption capacities of the beads for Cd(II), Hg(II), and Pb(II) were investigated in aqueous media containing different amounts of these ions (5–750 mg/L) and at different pH values (3.0–7.0). The maximum adsorption capacities of the poly(EGDMA–VTAZ) beads were 85.7 mg/g (0.76 mmol/g) for Cd(II), 134.9 mg/g (0.65 mmol/g) for Pb(II), and 186.5 mg/g (0.93 mmol/g) for Hg(II). The affinity order toward triazole groups on a molar basis was observed as follows: Hg(II) > Cd(II) > Pb(II). pH significantly affected the adsorption capacity of the VTAZ-incorporated beads. The equilibrium data were well fitted to the Redlich–Peterson isotherm. Consideration of the kinetic data suggested that chemisorption processes could have been the rate-limiting step in the adsorption process. Regeneration of the chelating-beads was easily performed with 0.1M HNO3. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4276–4283, 2006
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poly ethylene glycol dimethacrylate n vinyl imidazole beads for heavy Metal Removal
Journal of Hazardous Materials, 2004Co-Authors: Ali Kara, Necati Besirli, Lokman Uzun, Adil DenizliAbstract:Abstract Poly(ethylene glycol dimethacrylate- n -vinyl imidazole) [poly(EGDMA–VIM)] hydrogel (average diameter 150–200 μm) was prepared by copolymerizing ethylene glycol dimethacrylate (EGDMA) with n -vinyl imidazole (VIM). The copolymer hydrogel bead composition was characterized by elemental analysis and found to contain 5 EGDMA monomer units each VIM monomer unit. Poly(EGDMA–VIM) beads had a specific surface area of 59.8 m 2 /g. Poly(EGDMA–VIM) beads were characterized by swelling studies and scanning electron microscopy (SEM). These poly(EGDMA–VIM) beads with a swelling ratio of 78% were used for the heavy Metal Removal studies. Chelation capacity of the beads for the selected Metal ions, i.e., Cd(II), Hg(II) and Pb(II) were investigated in aqueous media containing different amounts of these ions (10–750 mg/l) and at different pH values (3.0–7.0). Chelation rate was very fast. The maximum chelation capacities of the poly(EGDMA–VIM) beads were 69.4 mg/g for Cd(II), 114.8 mg/g for Pb(II) and 163.5 mg/g for Hg(II). The affinity order on molar basis was observed as follows: Hg(II)>Cd(II)>Pb(II). Chelation behavior of heavy Metal ions could be modelled using both the Langmuir and Freundlich isotherms. pH significantly affected the chelation capacity of VIM incorporated beads. Chelation of heavy Metal ions from synthetic wastewater was also studied. The chelation capacities are 45.6 mg/g for Cd(II), 74.2 mg/g for Hg(II) and 92.5 mg/g for Pb(II) at 0.5 mmol/l initial Metal concentration. Regeneration of the chelating-beads was easily performed with 0.1 M HNO 3 . These features make poly(EGDMA–VIM) beads potential candidate adsorbent for heavy Metal Removal.
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preparation of cibacron blue f3ga attached polyamide hollow fibers for heavy Metal Removal
Journal of Applied Polymer Science, 2002Co-Authors: Serap şenel, Adil DenizliAbstract:Dye-affinity adsorption has been used increasingly for heavy Metal Removal. Synthetic hollow fibers have advantages as support matrices in comparison to conventional bead supports because they are not compressible and they eliminate internal diffusion limitations. The goal of this study was to investigate in detail the performance of hollow fibers composed of modified polyamide to which Cibacron Blue F3GA was attached for the Removal of heavy Metal ions. The Cibacron Blue F3GA loading was 1.2 mmol/g. The internal matrix was characterized by scanning electron microscopy. No significant changes in the hollow fiber cross-section or outer layer morphology were observed after dye modification. The effect of the initial concentration of heavy Metal ions and medium pH on the adsorption efficiency were studied in a batch reactor. The adsorption capacity of the hollow fibers for the selected Metal ions [i.e., Cu(II), Zn(II) and Ni(II)] were investigated in aqueous media with different amounts of these ions (10–400 ppm) and at different pH values (3.0–7.0). The maximum adsorptions of Metal ions onto the Cibacron Blue F3GA-attached hollow fibers were 246.2 mg/g for Cu(II), 133.6 mg/g for Zn(II), and 332.7 mg/g for Ni(II). Furthermore, a Langmuir expression was calculated to extend the adsorption equilibrium. Nitric acid (0.1M) was chosen as the desorption solution. High desorption ratios (up to 97%) were observed in all cases. Consecutive adsorption/desorption operations showed the feasibility of repeated use of this novel sorbent system. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3089–3098, 2002; DOI 10.1002/app.2338
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cibacron blue f3ga incorporated macroporous poly 2 hydroxyethyl methacrylate affinity membranes for heavy Metal Removal
Journal of Chromatography A, 1997Co-Authors: Adil Denizli, Bekir Salih, Kemal Kesenci, M. Yakup Arica, Vasif Hasirci, Erhan PiskinAbstract:Abstract Macroporous poly(2-hydroxyethyl methacrylate), poly(HEMA), membranes were prepared by UV-initiated photopolymerization of HEMA in the presence of an initiator (azobisisobutyronitrile, AIBN). An affinity dye, i.e., Cibacron Blue F3GA was then incorporated covalently. These affinity membranes with a swelling ratio of 58%, and carrying 10.67 mmol Cibacron Blue F3GA/m 2 membrane were used in the adsorption/desorption of some selected heavy Metal ions [i.e., As(III), Cd(II) and Pb(II)] from aqueous media. Very high adsorption rates were observed and adsorption equilibria were reached in about 30 min. The maximum adsorptions of heavy Metal ions onto the dye-incorporated affinity membranes from their single solutions were 12.6 mmol/m 2 for As(III), 61.0 mol/m 2 for Cd(II) and 79.0 mol/m 2 for Pb(II). However, when the heavy Metal ions competed (in the case of the adsorption from their mixture) the amounts of adsorption for As(III), Cd(II) and Pb(II) were quite close. Desorption of heavy Metal ions was carried out by using 0.1 M HNO 3 (pH 1.0). Up to 95% of the adsorbed heavy Metal ions were desorbed in 60 min. Repeated adsorption/desorption cycles showed the feasibility of this novel affinity membrane for heavy Metal Removal.
Ronghua Li - One of the best experts on this subject based on the ideXlab platform.
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preparation of thiol functionalized activated carbon from sewage sludge with coal blending for heavy Metal Removal from contaminated water
Environmental Pollution, 2018Co-Authors: Juan Li, Congbin Xu, Xing Xing, Jiao Li, Jianzhong Zheng, Ronghua LiAbstract:Abstract Sewage sludge produced from wastewater treatment is a pressing environmental issue. Mismanagement of the massive amount of sewage sludge would threat our valuble surface and shallow ground water resources. Use of activated carbon prepared from carbonization of these sludges for heavy Metal Removal can not only minimize and stabilize these hazardous materials but also realize resources reuse. In this study, thiol-functionalized activated carbon was synthesized from coal-blended sewage sludge, and its capacity was examined for removing Cu(II), Pb(II), Cd(II) and Ni(II) from water. Pyrolysis conditions to prepare activated carbons from the sludge and coal mixture were examined, and the synthesized material was found to achieve the highest BET surface area of 1094 m2/g under 500 °C and 30 min. Batch equilibrium tests indicated that the thiol-functionalized activated carbon had a maximum sorption capacity of 238.1, 96.2, 87.7 and 52.4 mg/g for Pb(II), Cd(II), Cu(II) and Ni(II) Removal from water, respectively. Findings of this study suggest that thiol-functionalized activated carbon prepared from coal-blended sewage sludge would be a promising sorbent material for heavy Metal Removal from waters contaminated with Cu(II), Pb(II), Cd(II) and Ni(II).
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preparation of thiol functionalized activated carbon from sewage sludge with coal blending for heavy Metal Removal from contaminated water
Environmental Pollution, 2018Co-Authors: Juan Li, Congbin Xu, Xing Xing, Jiao Li, Jianzhong Zheng, Ronghua LiAbstract:Abstract Sewage sludge produced from wastewater treatment is a pressing environmental issue. Mismanagement of the massive amount of sewage sludge would threat our valuble surface and shallow ground water resources. Use of activated carbon prepared from carbonization of these sludges for heavy Metal Removal can not only minimize and stabilize these hazardous materials but also realize resources reuse. In this study, thiol-functionalized activated carbon was synthesized from coal-blended sewage sludge, and its capacity was examined for removing Cu(II), Pb(II), Cd(II) and Ni(II) from water. Pyrolysis conditions to prepare activated carbons from the sludge and coal mixture were examined, and the synthesized material was found to achieve the highest BET surface area of 1094 m2/g under 500 °C and 30 min. Batch equilibrium tests indicated that the thiol-functionalized activated carbon had a maximum sorption capacity of 238.1, 96.2, 87.7 and 52.4 mg/g for Pb(II), Cd(II), Cu(II) and Ni(II) Removal from water, respectively. Findings of this study suggest that thiol-functionalized activated carbon prepared from coal-blended sewage sludge would be a promising sorbent material for heavy Metal Removal from waters contaminated with Cu(II), Pb(II), Cd(II) and Ni(II).
Sui Zhang - One of the best experts on this subject based on the ideXlab platform.
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layer by layer construction of graphene oxide go framework composite membranes for highly efficient heavy Metal Removal
Journal of Membrane Science, 2016Co-Authors: Yu Zhang, Sui ZhangAbstract:Abstract In this study, an ultrathin graphene oxide (GO) framework layer was successfully deposited on a modified Torlon ® hollow fiber support via a layer-by-layer (LbL) approach, enabling the composite membrane with superior nanofiltration (NF) performance. To molecularly design the GO framework, the substrate layer was firstly cross-linked with polyethylenimine (HPEI), followed by repeating the GO and ethylenediamine (EDA) deposition cycles and then an amine-enrichment modification by HPEI. The combination of the GO framework layer and the Torlon ® support can not only effectively seal the defects of the composite membrane with a narrow pore size distribution but also reduce the polymer consumption for the fabrication of traditional integrally skinned NF membranes. The GO/Torlon ® composite membrane has rejections higher than 95% towards Pb 2+ , Ni 2+ , and Zn 2+ with a superior water permeability of 4.7 L m −2 h −1 bar −1 . The membrane also exhibits excellent long-term performance stability during a 150-h NF test. Thus, the newly developed membrane has great potential for heavy Metal Removal. This study may provide useful insights on the fabrication of new generation 2-dimensional (2D) NF membranes.
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nanometric graphene oxide framework membranes with enhanced heavy Metal Removal via nanofiltration
Environmental Science & Technology, 2015Co-Authors: Yu Zhang, Sui Zhang, Taishung ChungAbstract:A novel dual-modification strategy, including (1) the cross-linking and construction of a GO framework by ethylenediamine (EDA) and (2) the amine-enrichment modification by hyperbranched polyethylenimine (HPEI), has been proposed to design stable and highly charged GO framework membranes with the GO selective layer thickness of 70 nm for effective heave Metal Removal via nanofiltration (NF). Results from sonication experiments and positron annihilation spectroscopy confirmed that EDA cross-linking not only enhanced structural stability but also enlarged the nanochannels among the laminated GO nanosheets for higher water permeability. HPEI 60K was found to be the most effective post-treatment agent that resulted in GO framework membranes with a higher surface charge and lower transport resistance. The newly developed membrane exhibited a high pure water permeability of 5.01 L m–2 h–1 bar–1 and comparably high rejections toward Mg2+, Pb2+, Ni2+, Cd2+, and Zn2+. These results have demonstrated the great pote...
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poly amidoamine dendrimer pamam grafted on thin film composite tfc nanofiltration nf hollow fiber membranes for heavy Metal Removal
Journal of Membrane Science, 2015Co-Authors: Sui ZhangAbstract:Abstract This study provides a facile and effective method to modify thin film composite (TFC) hollow fiber nanofiltration (NF) membranes by grafting poly (amidoamine) dendrimer (PAMAM) on the interfacially polymerized layer of polyethersulfone (PES) membranes for heavy Metal Removal. The PAMAM grafting not only decreases the pore size of the composite membrane, but also provides the positively charged functional groups, such as tertiary amino groups (RH3N+ and R3HN+), on the membrane surface to improve the hydrophilicity and water permeability of the TFC membrane without compromising rejection. The resultant membrane possesses rejection over 99% against most tested heavy Metals like Pb2+, Cu2+, Ni2+, Cd2+, Zn2+ and As5+, with an outstanding pure water permeability (PWP) greater than 3.6 L m−2 h−1 bar−1 at 10 bar. The rejection of the membrane to As3+ is also impressive. It can reach 97% by changing the solution pH. Moreover, the membrane shows stable performance for at least 72 h under continuous testing. This PAMAM grafted TFC membrane may have great potential for heavy Metal Removal and other water treatment applications.
Kyujung Chae - One of the best experts on this subject based on the ideXlab platform.
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heavy Metal Removal from aqueous solutions using engineered magnetic biochars derived from waste marine macro algal biomass
Science of The Total Environment, 2018Co-Authors: Jaesoo Chang, Kyujung ChaeAbstract:Abstract Despite the excellent sorption ability of biochar for heavy Metals, it is difficult to separate and reuse after adsorption when applied to wastewater treatment process. To overcome these drawbacks, we developed an engineered magnetic biochar by pyrolyzing waste marine macro-algae as a feedstock, and we doped iron oxide particles (e.g., magnetite, maghemite) to impart magnetism. The physicochemical characteristics and adsorption properties of the biochar were evaluated. When compared to conventional pinewood sawdust biochar, the waste marine algae-based magnetic biochar exhibited a greater potential to remove heavy Metals despite having a lower surface area (0.97 m 2 /g for kelp magnetic biochar and 63.33 m 2 /g for hijikia magnetic biochar). Although magnetic biochar could be effectively separated from the solution, however, the magnetization of the biochar partially reduced its heavy Metal adsorption efficiency due to the biochar's surface pores becoming plugged with iron oxide particles. Therefore, it is vital to determine the optimum amount of iron doping that maximizes the biochar's separation without sacrificing its heavy Metal adsorption efficiency. The optimum concentration of the iron loading solution for the magnetic biochar was determined to be 0.025–0.05 mol/L. The magnetic biochar's heavy Metal adsorption capability is considerably higher than that of other types of biochar reported previously. Further, it demonstrated a high selectivity for copper, showing two-fold greater Removal (69.37 mg/g for kelp magnetic biochar and 63.52 mg/g for hijikia magnetic biochar) than zinc and cadmium. This high heavy Metal Removal performance can likely be attributed to the abundant presence of various oxygen-containing functional groups ( COOH and OH) on the magnetic biochar, which serve as potential adsorption sites for heavy Metals. The unique features of its high heavy Metal Removal performance and easy separation suggest that the magnetic algae biochar can potentially be applied in diverse areas that require biosorbents for pollutant Removal.
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biochars derived from wasted marine macro algae saccharina japonica and sargassum fusiforme and their potential for heavy Metal Removal in aqueous solution
Journal of Environmental Management, 2018Co-Authors: Kyungmin Poo, Jaesoo Chang, Eunbi Son, Xianghao Ren, Yunjung Choi, Kyujung ChaeAbstract:Abstract For the purpose of reusing wasted marine macro-algae generated during cultivation, harvesting, processing and selling processes, biochars derived from Saccharina japonica (known as kelp ) and Sargassum fusiforme (known as hijikia ) were characterized and their Removal capacities for Cu, Cd, and Zn in aqueous solution were assessed. Feedstocks, S. japonica, S. fusiforme, and also pinewood sawdust as a control, were pyrolyzed at 250, 400, 500, 600 and 700 °C. In evaluating heavy Metal Removal capacities, SJB ( S. japonica biochar) showed the best performance, with Removal efficiencies of more than 98% for the three heavy Metals when pyrolyzed at over 400 °C. SFB ( S. fusiforme biochar) also showed good potential as an adsorbent, with Removal efficiencies for the three heavy Metals of more than 86% when pyrolyzed at over 500 °C. On the contrary, the maximum Removal efficiencies of PSB (pinewood sawdust biochar) were 81%, 46%, and 47% for Cu, Cd, and Zn, respectively, even at 700 °C, the highest pyrolysis temperature. This demonstrates that marine macro-algae were advantageous in terms of production energy for removing heavy Metals even at relatively low pyrolysis temperatures, compared with PSB. The excellent heavy Metal adsorption capacities of marine macro-algae biochars were considered due to their higher pH and more oxygen-containing functional groups, although the specific surface areas of SJB and SFB were significantly lower than that of PSB. This research confirmed that the use of marine macro-algae as a heavy Metal adsorbent was suitable not only in the Removal of heavy Metals, but also in terms of resource recycling and energy efficiency.
Juan Li - One of the best experts on this subject based on the ideXlab platform.
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preparation of thiol functionalized activated carbon from sewage sludge with coal blending for heavy Metal Removal from contaminated water
Environmental Pollution, 2018Co-Authors: Juan Li, Congbin Xu, Xing Xing, Jiao Li, Jianzhong Zheng, Ronghua LiAbstract:Abstract Sewage sludge produced from wastewater treatment is a pressing environmental issue. Mismanagement of the massive amount of sewage sludge would threat our valuble surface and shallow ground water resources. Use of activated carbon prepared from carbonization of these sludges for heavy Metal Removal can not only minimize and stabilize these hazardous materials but also realize resources reuse. In this study, thiol-functionalized activated carbon was synthesized from coal-blended sewage sludge, and its capacity was examined for removing Cu(II), Pb(II), Cd(II) and Ni(II) from water. Pyrolysis conditions to prepare activated carbons from the sludge and coal mixture were examined, and the synthesized material was found to achieve the highest BET surface area of 1094 m2/g under 500 °C and 30 min. Batch equilibrium tests indicated that the thiol-functionalized activated carbon had a maximum sorption capacity of 238.1, 96.2, 87.7 and 52.4 mg/g for Pb(II), Cd(II), Cu(II) and Ni(II) Removal from water, respectively. Findings of this study suggest that thiol-functionalized activated carbon prepared from coal-blended sewage sludge would be a promising sorbent material for heavy Metal Removal from waters contaminated with Cu(II), Pb(II), Cd(II) and Ni(II).
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preparation of thiol functionalized activated carbon from sewage sludge with coal blending for heavy Metal Removal from contaminated water
Environmental Pollution, 2018Co-Authors: Juan Li, Congbin Xu, Xing Xing, Jiao Li, Jianzhong Zheng, Ronghua LiAbstract:Abstract Sewage sludge produced from wastewater treatment is a pressing environmental issue. Mismanagement of the massive amount of sewage sludge would threat our valuble surface and shallow ground water resources. Use of activated carbon prepared from carbonization of these sludges for heavy Metal Removal can not only minimize and stabilize these hazardous materials but also realize resources reuse. In this study, thiol-functionalized activated carbon was synthesized from coal-blended sewage sludge, and its capacity was examined for removing Cu(II), Pb(II), Cd(II) and Ni(II) from water. Pyrolysis conditions to prepare activated carbons from the sludge and coal mixture were examined, and the synthesized material was found to achieve the highest BET surface area of 1094 m2/g under 500 °C and 30 min. Batch equilibrium tests indicated that the thiol-functionalized activated carbon had a maximum sorption capacity of 238.1, 96.2, 87.7 and 52.4 mg/g for Pb(II), Cd(II), Cu(II) and Ni(II) Removal from water, respectively. Findings of this study suggest that thiol-functionalized activated carbon prepared from coal-blended sewage sludge would be a promising sorbent material for heavy Metal Removal from waters contaminated with Cu(II), Pb(II), Cd(II) and Ni(II).
