Biosorption removal of cadmium from aqueous solution by using pretreated fungal biomass cultured from starch wastewater

The biosorption removal of cadmium ions from aqueous solutions by using the fungal biomass obtained from cultivation using starch wastewater as a substrate was investigated. Batch experimental results showed that the biosorption capacities of the pretreated fungal biomass of R. oryzae, R. oligosporus, A. oryzae and R. arrhizus were up to 0.28, 0.35. 0.40 and 0.56 mmol Cd2+/g (dry weight), respectively. Pretreatment of the biomass with calcium solution and heat improved the stability and settling property and increased heavy metal uptake capacities of the biomass. The biosorption capacities were solution pH dependent. The effects of other cations (Pb2+, Cu2+. Cd2+ and Zn2+) were also investigated and the biosorption affinity sequence for the biomass is Pb2+ > Cu2+ > Cd2+ > Zn2+. This study indicated that the fungal biomass of R. arrhizus has a high capacity for cadmium. (C) 1999 Elsevier Science Ltd. All rights reserved.