Removal of hexavalent chromium from aqueous solution by adsorption on treated sugarcane bagasse using response surface methodological approach

In the present study, effect of adsorbent dose, pH and agitation speed on the removal of chromium from aqueous medium using an agricultural waste biomass (sugarcane bagasse treated with succinic acid) has been investigated. Batch mode experiments were carried out to assess the adsorption equilibrium. The influence of three parameters on the removal of chromium was examined using a response surface methodological approach. The Central Composite Face-Centered Experimental Design in Response Surface Methodology (RSM) by Design Expert Version 6.0.10 (Stat Ease, USA) was used for designing the experiments as well as for full response surface estimation and 20 trials as per the model were run. The optimum conditions for maximum removal of chromium from an aqueous solution of 50 mg/L were as follows: adsorbent dose (20 g/L), pH (2.0) and stirring speed (250 rpm). This was evidenced by the higher value of coefficient of determination (r2 = 0.9873).