Biosorption of chromium VI by free and immobilized Rhizopus arrhizus

Biosorption of chromium (VI) was studied by using non-living free and immobilized biomass of Rhizopus arrhizus at pH 2. A biphasic chromium adsorption pattern was observed in all experimental conditions. Chromium removal rate was slightly more in free biomass conditions over immobilized state. Stirred tank reactor studies indicated maximum chromium biosorption at 100 rpm and at 1:10 biomass–liquid ratio. Fluidized bed reactor is more efficient in chromium removal over stirred tank reactor. Immobilization of biomaterial has a little effect on chromium biosorption by this R. arrhizus biomass. ©