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Öğe Application of NaOH treated Polyporus versicolor for removal of divalent ions of Group IIB elements from synthetic wastewater(Elsevier Sci Ltd, 2002) Satiroglu, N.; Yalcinkaya, Y.; Denizli, A.; Arica, M.Y.; Bektas, S.; Genç, O.Three different forms of Polyporus versicolor, i.e. alkali-pretreated, heat-inactivated and active, were used for the removal of the divalent ions of Group JIB elements from aquatic systems. The biosorption of Zn(II), Cd(II) and Hg(II) ions on three different forms of P. versicolor was studied in aqueous solutions in the concentration range of 30-700 mg/l. Maximum biosorption capacities of alkali-pretreated, heat-inactivated and active forms of P. versicolor was found as 139.3, 70.8, and 54.1 mg/g for Zn(II); 232.2, 118.2, and 90.0 mg/g for Cd(II) and 290.3 168.9, and 131.4 mg/g for Hg(11), respectively. For the divalent ions of Group 1111 elements, the order of affinity of the biosorbents was found as, NaOH treated > heat-inactivated > active. The order of the amount of metal ions adsorbed, on the other hand, was, Hg(II) > Cd(II) > Zn(II) on a weight base. The electro-negativities and standard electrode potentials of these elements show a definite trend with the biosorption capacity values. Biosorption equilibria were established in about 60 min and the equilibria were well described by Langmuir isotherms. Temperature change between 15 and 45 degreesC did not affect the biosorption capacity. The effect of pH was also investigated and the maximum biosorption of metal ions on the three different forms of P. versicolor were observed at pH 6.0. The reusability experiments and synthetic wastewater studies were carried out with the most effective form; alkali-pretreated P. versicolor. The biosorbent could be regenerated using 10 mM HCl solution, with up to 98% recovery and it could be reused in five biosorption-desorption cycles without any considerable loss in biosorption capacity. The alkali-treated P. versicolor removed 60, 73, and 81% of Zn(II), Cd(II) and Hg(II) ions from synthetic wastewater samples, respectively. (C) 2002 Elsevier Science Ltd. All rights reserved.Öğe Ca-alginate as a support for Pb(II) and Zn(II) biosorption with immobilized Phanerochaete chrysosporium(Elsevier Sci Ltd, 2003) Arica, M.Y.; Arpa, C.; Ergene, A.; Bayramoglu, G.; Genç, O.The basidio spores of Phanerochaete chryosporium were immobilized in alginate gel beads, and the immobilized spore containing alginate beads were incubated for the growth of fungus. The biosorption of Pb2+ and Zn2+ ions on alginate beads and both immobilized live and heat inactivated fungus was studied from artificial waste waters in the concentrations range of 30-600 mg 1(-1). The surface charge density of the biosorbents varied with the pH of the medium and the maximum biosorption of heavy metal ions on the biosorbents was obtained between pH 5.0 and 6.0. The biosorption of Pb2+ and Zn2+ on the biosorbents increased as the initial concentration of Pb2+ and Zn2+ ions increased in the medium. Biosorption equilibrium was established about 1 h, the adsorbed heavy metal ions did not significantly change further with time. The maximum biosorption capacity (q(m)) of alginate beads and both immobilized live and heat inactivated fungus were 230, 282 and 355 mg for Pb2+ and 30, 37 and 48 mg for Zn per gram of dry biosorbents, respectively. The experimental biosorption equilibrium data for Pb2+, and Zn2+ ions were in good agreement with those calculated by Langmuir model. The affinity order of heavy metal ions was Pb2+ > Zn2+, (C) 2003 Elsevier Science Ltd. All rights reserved.Öğe Cadmium and mercury uptake by immobilized Pleurotus sapidus(Scientific Technical Research Council Turkey, 2002) Yalçınkaya, Y.; Arıca, M.Y.; Soysal, L.; Denizli, A.; Genç, O.; Bektaş, S.Pleurotus sapidus basidiospores immobilized onto Ca-alginate beads were used for the removal of cadmium and mercury ions from aqueous solutions. The biosorption of Cd(II) and Hg(II) ions on the alginate beads and both immobilized live and heat inactivated fungal mycelia of Pleurotus sapidus was studied from aqueous solutions in the concentration range of 30-500 mg L-1. The biosorption of Cd(II) and Hg(II) ions by the alginate and both live and heat inactivated immobilized preparations increased as the initial concentration of the ions increased in the medium. Maximum biosorption capacity for immobilized live and heat inactivated fungal mycelia of Pleurotus sapidus was found to be 96.57 mg g(-1) (0.86 mmol g(-1)) and 127.12 mg g(-1) (1.13 mmol g(-1)) for Cd(II) and 207.89 mg g(-1)(1.04 mmol g(-1)) and 287.43 mg g(-1) (1.43 mmol g(-1)) for Hg(II), respectively. The electronegativities and standard electrode potentials of the divalent ions of Group II elements show a definite trend with sorption capacity. Biosorption equilibria were established in about I h and were very well described by Langmuir isotherms. The temperature change between 1.5 and 4.5degreesC did not affect the biosorption capacity. The effect of pH was also investigated and the maximum uptake of metal ions on the alginate and both live and inactivated immobilized fungal mycelia were observed between pH 3.0 and 7.0. The alginate-fun.-us beads were regenerated using 10 mM HCl, with up to 97% recovery, the biosorbents were reused in three biosorption-desorption cycles without any considerable loss in the biosorption capacity.Öğe Comparison of the heavy metal biosorption capacity of active, heat-inactivated and NaOH-treated phanerochaete chrysosporium biosorbents(Wiley, 2004) Gurisik, E.; Arica, M.Y.; Bektas, S.; Genç, O.Three different kinds of Phanerochaete chrysosporium (NaOH-treated, heat-inactivated and active) biosorbent were used for the removal of Cd(II) and Hg(II) ions from aquatic systems. The biosorption of Cd(II) and Hg(II) ions on three different forms of Phanerochaete chrysosporium was studied in aqueous solutions in the concentration range of 50-700 mg/ L. Maximum biosorption capacities of NaOH-treated, heat-inactivated and active Phanerochaete chrysosporium biomass were found to be 148.37 mg/g, 78.68 mg/g and 68.56 mg/g for Cd(II) as well as 224.67 mg/g, 122.37 mg/g and 88.26 mg/g for Hg(II), respectively. For Cd(II) and Hg(II) ions, the order of affinity of the biosorbents was arranged as NaOH-treated > heat-in activated > active. The order of the amount of metal ions adsorbed was established as Hg(II) > Cd(II) on a weight basis, and as Cd(II) > Hg(II) on a molar basis. Biosorption equilibriums were established in about 60 min. The effect of the pH was also investigated, and maximum rates of biosorption of metal ions on the three different forms of Phanerochaete chrysosportum were observed at pH 6.0. The reusability experiments and synthetic wastewater studies were carried out with the most effective form, i.e., the NaOH-treated Phanerochaete chrysosporium biomass. It was observed that the biosorbent could be regenerated using 10 mM HCl solution, with a recovery of up to 98%, and it could be reused in five biosorption-desorption cycles without any considerable loss in biosorption capacity. The alkali-treated Phanerochaete chrysosporium removed 73% of Cd(II) and 81% of Hg(II) ions from synthetic wastewater.Öğe Dye-ligand immobilized IPNs membrane for removal heavy metal ions(Wiley-V C H Verlag Gmbh, 2003) Bayramoğlu, G.; Yalçın, E.; Genç, O.; Arica, M.Y.We have developed a novel approach to obtain high metal sorption capacity utilizing a membrane containing chitosan and an immobilized reactive dye (i.e. Reactive Yellow-2). The composite membrane was characterized by SEM, FTIR, swelling test, and elemental analysis. The membrane has uniform small pores distribution and the pore dimensions are between 5 and 10 pm, and the HEMA:chitosan ratio was 50:1. The reactive dye immobilized composite membrane was used in the removal of heavy metal ions [i.e., Pb(II), Hg(II) and Cd(II)] from aqueous medium containing different amounts of these ions (5-600 mg 1(-1)) and at different pH values (2.0-7.0). The maximum adsorption capacities of heavy metal ions onto the composite membrane under non-competitive conditions were 64.3 mmol m(-2) for Pb(II), 52.7 mmol m(-2) for Hg(II), 39.6 mmol m(-2) for Cd(II) and the affinity order was Pb(II) > Hg(II)>Cd(II).Öğe Procion Green H-4G immobilized poly(hydroxyethylmethacrylate/chitosan) composite membranes for heavy metal removal(Elsevier Science Bv, 2003) Genç, O.; Soysal, L.; Bayramoglu, G.; Arica, M.Y.; Bektas, S.The effective removal of toxic heavy metals from environmental samples still remains a major topic of present research. Metal-chelating membranes are very promising materials as adsorbents when compared with conventional beads because they are not compressible, and they eliminate internal diffusion limitations. The purpose of this study was to evaluate the performance of a novel adsorbent, Procion Green H-4G immobilized poly(hydroxyethylmethacrylate (HEMA)/chitosan) composite membranes, for the removal of three toxic heavy metal ions, namely, Cd(II), Pb(II) and Hg(II) from aquatic systems. The Procion Green H-4G immobilized poly(hydroxyethylmethacrylate/chitosan) composite membranes were characterized by elemental analysis, scanning electron microscopy and Fourier transform infrared (FTIR) spectroscopy. The immobilized amount of the Procion Green H-4G was calculated as 0.018 +/- 0.003 mumol/cm(2) from the nitrogen and sulphur stoichiometry. The adsorption capacity of Procion Green H-4G immobilized poly(hydroxyethylmethacrylate/chitosan) composite membranes for selected heavy metal ions from aqueous media containing different amounts of these ions (30-400 mg/l) and at different pH values (2.0-6.0) was investigated. The amount of Cd(II), Pb(II) and Hg(II) adsorbed onto the membranes measured at equilibrium, increased with time during the first 45 min and then remained unchanged toward the equilibrium adsorption. The maximum amounts of heavy metal ions adsorbed were 43.60 +/- 1.74, 68.81 +/- 2.75 and 48.22 +/- 1.92 mg/g for Cd(II), Pb(II) and Hg(II), respectively. The heavy metal ion adsorption on the pHEMA/chitosan membranes (carrying no dye) were relatively low, 6.31 +/- 0.13 mg/g for Cd(II), 18.73 +/- 0.37 mg/g for Pb(II) and 18.82 +/- 0.38 mg/g for Hg(II). Competitive adsorption of the metal ions was also studied. When the metal ions competed with each other, the adsorbed amounts were 12.74 +/- 0.38 mg Cd(II)/g, 28.80 +/- 0.86 mg Pb(II)/g and 18.41 +/- 0.54 mg Hg(II)/g. Procion Green H-4G immobilized poly(hydroxyethylmethacrylate/chitosan) membranes can be regenerated by washing with a solution of nitric acid (0.01 M). The percent desorption achieved was as high as 95%. These novel membranes are suitable for repeated use for more than five adsorption/desorption cycles without any considerable loss in adsorption capacity. Adsorption equilibria were well described by Langmuir equation. It can be concluded that Procion Green H-4G immobilized poly(hydroxyethylmethacrylate/chitosan) membranes may effectively be used for the removal of Cd(II), Pb(II) and Hg(II) ions from aqueous solutions. (C) 2002 Elsevier Science B.V. All rights reserved.Öğe Selective recovery of mercury by Procion Brown MX 5BR immobilized poly(hydroxyethylmethacrylate/chitosan) composite membranes(Elsevier Science Bv, 2002) Genç, O.; Arpa, C.; Bayramoğlu, G.; Arıca, M.Y.; Bektaş, S.Metal chelating membranes have advantages as adsorbents in comparison to conventional microspheres or beads because they are not compressible and they considerably eliminate internal diffusion limitations. The aim of this communication was to explore in detail the performance of Procion Brown MX 5BR immobilized poly(hydroxyethylmethacrylate/chitosan) composite membranes, (also called interpenetrating network, IPN, membranes) for removal of three toxic heavy metal ions, namely, Cd(II), Pb(II) and Hg(II) from aquatic systems. The composite membranes were characterized by elemental analysis, scanning electron microscopy and Fourier Transform Infrared (FTIR) spectroscopy. The incorporated amount of the Procion Brown NIX 5BR was calculated. as 0.036 mumol/cm(2) from the nitrogen and sulphur stoichiometry. The adsorption capacity for selected heavy metal ions from aqueous media containing different amounts of these ions (30-400 mg/L) and at different pH values (2.0-6.0) was investigated. Adsorption capacity of the membranes increased with time during the first 45 min and then levelled off toward the equilibrium adsorption. The maximum amounts of heavy metal ions adsorbed were found as 18.5, 22.7 and 68.8 mg/g for Cd(H), Pb(H) and Hg(H), respectively. Competitive adsorption of the metal ions was also studied. When the metal ions competed, the adsorbed amounts were found as 1.8 mg Cd(II)/g, 2.2 mg Pb(II)/g and 52.6 mg Hg(II)/g. Under competitive conditions, the system showed a very high selectivity for Hg(H) ions. The membrane can be regenerated by washing with a solution of nitric acid (0.01 M). The desorption ratio achieved was as high as 95%. These membranes are suitable for repeated use for more than five adsorption/desorption cycles without any considerable loss in adsorption capacity. (C) 2002 Elsevier Science B.V. All rights reserved.
