Kinetics of the biosorptive removal of chromium from water using mycelial biomass of Aspergillus oryzae

Abstract

Chromium is one of the highly toxic heavy metals and a chief pollutant in soil and water. Present study describes an efficient biosorption system for the chromium removal from water using mycelia of Aspergillus oryzae. The effect of different variables like pH, initial chromium conc., size of biomass and time of contact on the chromium uptake by A. oryzae was studied and it was found that absolute elimination of chromium from the aquous medium was achieved after 96 hrs of contact. The removal percentage of Cr(VI) was enhanced by increasing pH from 3.0 to 5.0 and then started decreasing. Similarly the removal of Cr(VI) was enhanced by increasing biomass concentration upto 0.7 g/50 mL chromium solution while this removal was decreased by increasing Cr(VI) concentration in the solution from 50 to 100 µg/mL. Langmuir and Freundlich models were applied to the data after experimentation and Freundlich equation was found to be better fitted to the data.