The present study deals with the adsorption of Cr(VI) on carbonized wheat straw (CWS) and barley straw (CBS). Carbon materials, prepared at different carbonization temperatures, were investigated for the adsorptive removal of Cr(VI). These carbonized materials prepared from agro-waste were found to have a high affinity for chromium as represented by very high adsorption capacities of 1.67 and 1.68 mol/kg for wheat and barley straws, respectively, carbonized at 800 degrees C at pH 2. Equilibrium was reached within 1 h of contact time which suggests high efficiency of the carbonized materials for Cr(VI) removal. (c) 2008 Elsevier B.V. All rights reserved.