A highly active and stable SO42-/gamma-Al2O3 catalyst was developed, and the catalytic activity was evaluated for esterification of glycerol. The reactions were performed in a batch reactor under reflux conditions. The influence of reaction conditions, such as the reaction temperature, catalyst amount, and acetic acid/glycerol mole ratio, on the product distribution was investigated. The results demonstrated that the 2 M SO42-/gamma-Al2O3 catalyst was very active and showed 100% glycerol conversion with 77.4% selectivity of higher esters [glycerol diacetate (DAG) + glycerol triacetate (TAG)] at 95 degrees C, after 5 h of reaction time in the presence of acetic acid/glycerol mole ratio of 12:1. Further, response surface methodology (RSM) was used for the development of the empirical process model, followed by the optimization of reaction parameters. The optimization process depicted that 76.1% combined selectivity to DAG and TAG can be achieved at complete conversion of glycerol at 108.8 degrees C in the presence of 0.36 g of catalyst at the acetic acid/glycerol mole ratio of 12:1.