title: Removal of chromate anions from aqueous stream by a cationic surfactant-modified yeast.
abstract: The removal of chromate anions (CrO(4)(2-)) from aqueous solution by a cationic surfactant-modified yeast was studied in a batch system. Cetyl trimethyl ammonium bromide (CTAB) was used for biomass modification; it substantially improved the biosorption efficiency. The influences of solution pH, CrO(4)(2-) anion concentrations and biomass concentration on the biosorption efficiency were investigated. The biosorption of chromate anions by modified yeast was strongly affected by pH. The optimum pH for biosorption of CrO(4)(2-) by modified yeast was 4.5-5.5. Zeta potential values of modified and unmodified yeast were determined at various pH values. Concentrations ranging from 5.2 to 208 mg/l Cr(VI) were tested and the biosorptive removal efficiency of the metal ions from aqueous solution was more than 99.5%. Freundlich and Langmuir isotherms were used to evaluate the data and the regression constants were determined.
authors.affiliation: Department of Environmental Engineering, Atatürk University, Erzurum 25240, Turkey.
authors.forename: Atifet
authors.initials: A
authors.lastname: Bingol
authors.forename: Handan
authors.initials: H
authors.lastname: Ucun
authors.forename: Yalcin Kemal
authors.initials: YK
authors.lastname: Bayhan
authors.forename: Ahmet
authors.initials: A
authors.lastname: Karagunduz
authors.forename: Avni
authors.initials: A
authors.lastname: Cakici
authors.forename: Bulent
authors.initials: B
authors.lastname: Keskinler
mesh_terms: D000327:Adsorption; D018533:Biomass; D000077286:Cetrimonium; D002593:Cetrimonium Compounds; D002840:Chromates / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D012044:Regression Analysis; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000379:methods*; D015003:Yeasts / Q000378:metabolism*
chemical_list: D002593:Cetrimonium Compounds; D002840:Chromates; D014874:Water Pollutants, Chemical; D000077286:Cetrimonium