Box-Behnken optimization of glycerol transesterification reaction to glycerol carbonate over calcined oil palm fuel ash derived catalyst

Abstract This study aimed to optimize the synthesis of valuable glycerol carbonate (GC) over calcined oil pam fuel ash derived catalyst. A surface response methodology optimization study was conducted using the Box-Behnken optimization tool to minimize the reaction parameters and optimize GC yield and glycerol conversion. Also, the effect of intraparticle and external mass transfer resistance was conducted and the intrinsic kinetic model of the transesterification reaction was established. Overall, the transesterification temperature had significant effects on the variables of GC yield and glycerol conversion, while the catalyst loading and reaction time trivially affected the response parameters. Under optimized parameters of 80 °C reaction temperature, dimethyl carbonate (DMC)/glycerol molar ratio of 5, 5 wt% catalyst loading and 112 min reaction time, GC reached 95% with a desirability of 1. Theoretical elucidation indicates that transesterification reaction over the catalyst was unaffected by external mass transfer resistance and intraparticle diffusion above 125 μ m particle size. The catalyst is heterogeneous and can be reused for five times while sustaining about 81.3% of GC yield.