Lead biosorption by different morphologies of fungus Mucor indicus

Abstract Biosorption characteristics of Pb +2 ions from aqueous solution were investigated using fungus Mucor indicus biomass treated with NaOH. Biosorption was measured as a function of biomass morphology, pH, biomass concentration, contact time, and metal concentration. The morphology of M. indicus biomass was manipulated towards filamentous or yeast-like forms. The highest and lowest biosorption capacities were observed for purely filamentous and yeast-like forms, respectively. Models of Langmuir, Freundlich, Temkin, and Scachard were applied to describe adsorption isotherm and fitted appropriately. Biosorption kinetics was successfully described using Ho’s pseudo-second-order model. Maximum and minimum values of biosorption capacity of Pb 2+ were 22.1 and 12.1 mg g −1 for purely filamentous and yeast-like morphologies, respectively. Increasing pH resulted in higher biosorption of Pb +2 ions up to pH 5.5. Biosorption capacity of individual Pb +2 ions was reduced in the presence of other metal ions in bi- or multi-metal ion experiments. Metal ions adsorption by the biomass could be eluted effectively with HNO 3 .