Efficient biosorptive removal of chromium(VI)

This paper reports the high biosorptive properties of an indigenous plant for Cr(VI) biosorption. The biomass uptake capacity is found 85 mg Cr(VI)/gm of biomass in batch mode. The influence of different experimental parameters such as pH, dose of adsorbent and Cr(VI) levels (15-200 mg/l), effect of contact time etc. on biosorption was evaluated. The adsorption data fitted well to Langmuir and Freundlich isotherm models. Kinetic experiments revealed that the dilute chromium solutions reached equilibrium within 120 minutes. It was observed that the pH had a strong effect on biosorption capacity. Desorption of Cr(VI) was successfully carried out by 0.1 N hydrochloric acid. The interference study of metals like Mn, Fe, Cu, Cd, Mo, Ni, Pb, As, Co (10mg/l) was investigated. Cd showed negative interference in this investigation.