title: Cationic surfactant-modified biosorption of anionic dyes by dried Rhizopus arrhizus.
abstract: The biosorption of an anionic dye Remazol Black B onto a filamentous, dried fungus, Rhizopus arrhizus, was studied in the presence of the cationic surfactant cetyl trimethyl ammonium bromide (CTAB), which was used as a pH shifter. Without surfactant, the maximum dye uptake capacity was achieved at pH 2.0 and was 434.0 mg dye g-1dried fungal biomass. Again, without surfactant, the highest dye uptake capacity, 27.8 mg dye g-1dried biomass, occurred at pH 8.0 calculated from the Langmuir adsorption model. Addition of CTAB changed the pH at which the highest dye uptake was obtained. At an initial pH of 8.0 with different CTAB concentrations, the dye uptake capacity increased from 27.8 to 500.0 mg dye g-1dried biomass. Furthermore, when 200 mg L-1surfactant was added to the biosorption medium at pH 8.0, the amount of dye removed increased significantly. Four equilibrium adsorption models were applied to the results. The applicability of each isotherm was determined using regression correlation and fitting curves. According to the Langmuir model, without surfactant, the highest dye removal capacity at pH 8.0 was found to be 27.8 mg dye g-1dried biomass, rising to 500.0 mg g-1dried biomass with 200 mg L-1CTAB.
authors.affiliation: a Department of Chemical Engineering , Hacettepe University , Ankara , Turkey.
authors.forename: Süheyla Pınar
authors.initials: SP
authors.lastname: Kodal
authors.affiliation: a Department of Chemical Engineering , Hacettepe University , Ankara , Turkey.
authors.forename: Zümriye
authors.initials: Z
authors.lastname: Aksu
mesh_terms: D000327:Adsorption; D018533:Biomass; D004396:Coloring Agents / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D012233:Rhizopus; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D004396:Coloring Agents; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical
keywords: Biosorption; Remazol Black B; Rhizopus arrhizus; pH shifter; surfactant (CTAB)