Abstract
Rice straw-derived biochars carbonize at different temperature (550, 650, 750 degrees C) used for Sr2+ removal. Experimental parameters affecting the sorption process like pH, contact time, sorbent concentration, and temperature were investigated. Sorption profile showed an initial rapid uptake which decreased and became almost constant after one hour. Optimum Sr2+ sorption was achieved at pH 6. Sorption kinetics good correlated with both pseudo-secondorder and Elovich kinetic equations. Isotherm model of Dubinin-Radushkevich provides the best correlation of Sr2+ sorption. The present biochar shows better sorption performance (198 mg/g) of Sr2+ than many types of sorbents. Adsorption of Sr2+ on biochar was endothermic and increase upon solution temperature rises from 25 to 55 degrees C. Present investigation emphasized that the rice straw-based biochar exhibited a high potential for Sr2+ removal from aqueous solution.