Batch removal of sexivalent chromium by Azolla filiculoides

Abstract

The results of batch adsorption experiments indicate that Azolla filiculoides, a naturally abundant biomass, is able to accumulate large amounts of sexivalent chromium from aqueous solution at low pH values. The adsorption equilibria were found to follow Langmuir models. The maximum adsorption capacity was estimated to be 70.6 mg/g at 18 °C and 120.2 mg/g at 32 °C, both at pH 2. The metal removal was moderately rapid at low initial Cr 6+ concentration.