Adsorption has shown a promising solution for treating heavy metal contaminated water. The biosorption of Cr (VI) ions from synthetic aqueous solutions using dead and dried fungal biomass of Aspergillusniger, was studied under batch conditions. These experiments were performed to optimize the parameters: equilibrium time, initial pH of the solution (range: pH 2.52–12.1), biosorbent concentration (range: 1–20g/L) and adsorbate concentration (range: 10-500mg/L).From all these batch studies it was found that, the optimum parameters for this biosorption process were 360mins of contact time to reach equilibrium, initial solution pH 8, 1g/L of A.niger biomass concentration and 500mg/L of Cr(VI)concentration of the solution. With all these optimum factors, A.niger biosorption capacity of 198.21mg/g could be achieved. Langmuir and Freundlich isotherm models were studied for the biosorption process. Freundlich isotherm fitted best for the biosorption process followed by the Langmuir isotherm. Adsorption kinetic studies using pseudo-first order and pseudo[1]second order kinetic models were performed. The biosorption kinetics followed pseudo-second order kinetic model better than pseudo-first order kinetic model. These results indicate the potential use of Aspergillusniger biomass for removal of high Cr(VI) ion concentrations from industrial effluents.
