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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 Biosorption of cadmium from aquatic systems by carboxymethyleellulose and immobilized Trametes versicolor(Elsevier Science Bv, 2002) Yalcinkaya, Y.; Soysal, L.; Denizli, A.; Arica, M.Y.; Bektas, S.; Genc, O.Trametes versicolor basidio spores immobilized onto carboxymethylcellulose were used for the removal of cadmium ions from aqueous solutions. The biosorption of Cd(II) ions on carboxymethylcellulose and both immobilized live and heat-killed fungal mycelia of T. versicolor was studied from aqueous solutions in the concentration range of 30-700 mg/L. The biosorption of Cd(II) ions by the carboxymethylcellulose and both immobilized live and heat-inactivated immobilized preparations increased as the initial concentration of cadmium ions increased in the medium. Maximum biosorption capacity for immobilized live and heat-inactivated fungal mycelia of T. versicolor was found as 124 and 153 mg Cd(II)/g, respectively whereas the amount of Cd(II) ions adsorbed on the plain carboxymethylcellulose beads was 43 mg/g. Biosorption equilibria were established in about I h and the correlation regression coefficients show that the adsorption process can be well defined by Langmuir equation. The temperature change between 15 and 45 degreesC did not affect the biosorption capacity. The effect of pH was also investigated and the maximum adsorption of Cd(II) ions on the carboxymethylcellulose and both live and heat-inactivated immobilized fungal mycelia were observed at pH 6.0. The carboxymethylcellulose-fungus beads could be regenerated using 10 mM HCl, with up to 98% recovery. The biosorbents were used in five biosorption-desorption cycles and no notable loss in the biosorption capacity was observed. 84% and 68% of cadmium ions were removed from synthetic waste water samples for 100 and 200 mg/L initial concentrations, respectively. (C) 2002 Elsevier Science B.V. All rights reserved.Öğe Biosorption of mercury by carboxymethylcellulose and immobilized Phanerochaete chrysosporium(Elsevier Science Bv, 2002) Saglam, A.; Yalcinkaya, Y.; Denizli, A.; Arica, M.Y.; Genc, O.; Bektas, S.Phanerochaete chrysosporium basidiospores immobilized onto carboxymethylcellulose were used for the removal of mercury ions from aqueous solutions. The biosorption of Hg(II) ions onto carboxymethylcellulose and both immobilized live and heat-inactivated fungal mycelia of Phanerochaete chrysosporium was studied using aqueous solutions in the concentration range 30-700 mg l(-1). The biosorption of Hg(II) ions by the carboxymethylcellulose and both live and heat-inactivated immobilized preparations increased as the initial concentration of mercury ions increased in the medium. Maximum biosorption capacity for immobilized live and heat-inactivated fungal mycelia of Phanerochaete chrysosporium was found to be 83.10 and 102.15 mg Hg(II) g(-1), respectively, whereas the amount of Hg(II) ions adsorbed onto the plain carboxymethylcellulose beads was 39.42 mg g(-1). Biosorption equilibria were established in approximately 1 h and the correlation regression coefficients show that the adsorption process can be well defined by a Langmuir equation. Temperature changes between 15 and 45 C did not affect the biosorption capacity. The effect of pH was also investigated and the maximum adsorption of Hg(II) ions onto the carboxymethylcellulose and both live and heat-inactivated immobilized fungal mycelia was observed at pH 6.0. The carboxymethylcellulose-fungus beads could be regenerated using 10 mM HCl, with up to 95% recovery. The biosorbents were used in three biosorption-desorption cycles and no significant loss in the biosorption capacity was observed. (C)2002 Elsevier Science B.V All rights reserved.Öğe Comparative biosorption of mercuric ions from aquatic systems by immobilized live and heat-inactivated Trametes versicolor and Pleurotus sajur-caju(Elsevier Sci Ltd, 2003) Arica, M.Y.; Arpa, C.; Kaya, B.; Bektas, S.; Denizli, A.; Genc, O.Trametes versicolor and Pleurotus sajur-caju mycelia immobilized in Ca-alginate beads were used for the removal of mercuric ions from aqueous solutions. The sorption of Hg(II) ions by alginate beads and both immobilized live and heat-killed fungal mycelia of T versicolor and P. sajur-caju was studied in the concentration range of 0.150-3.00 mmol dm(-3). The biosorption of Hg(II) increased as the initial concentration of Hg(II) ions increased in the medium. Maximum biosorption capacities for plain alginate beads were 0.144+/-0.005 mmol Hg(II)/g; for immobilized live and heat-killed fungal mycelia of T versicolor were 0.171+/-0.007 mmol Hg(II)/g and 0.383+/-0.012 mmol Hg(II)/g respectively; whereas for live and heat-killed P. sajur-caju, the values were 0.450+/-0.014 mmol Hg(II)/g and 0.660+/-0.019 mmol Hg(II)/g respectively. Biosorption equilibrium was established in about 1 h and the equilibrium adsorption was well described by Langmuir and Freundlich adsorption isotherms. Between 15 and 45 degreesC the biosorption capacity was not affected and maximum adsorption was observed between pH 4.0 and 6.0. The alginate-fungus beads could be regenerated using 10 mmol dm(-3) HCl solution, with up to 97% recovery. The biosorbents were reused in five biosorption-desorption cycles without a significant loss in biosorption capacity. Heat-killed T versicolor and P. sajur-caju removed 73% and 81% of the Hg(II) ions, respectively, from synthetic wastewater samples. (C) 2003 Elsevier Science Ltd. All rights reserved.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 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.
