Characterization of carbon catalyst from palm kernel shell supported by cesium phosphotungstate for glycerol acetylation process

The valorization of surplus glycerol from biodiesel production into higher-value chemicals is a promising pathway to enhance both process sustainability and economic feasibility. In this study, carbon-based catalysts derived from palm kernel shells were synthesized and functionalized with cesium phosphotungstate (CsPWA) to evaluate their catalytic performance in the acetylation of glycerol. Catalyst characterization confirmed the preservation of the Keggin structure and the stability of active sites after synthesis. Among the tested catalysts, CsPWA30/C exhibited the highest performance, achieving 83.58 % glycerol conversion under conditions (110°C, 2 h reaction time, glycerol-to-acetic-acid molar ratio of 1:9, and 5 wt.% catalyst loading). The selectivity toward diacetin (67.31 %) and triacetin (32.69 %) demonstrated the catalyst’s efficiency in directing the reaction toward desirable acetylated products. The superior catalytic activity was attributed to the high surface acidity and stable structural framework of CsPWA, which facilitated efficient reactant diffusion. These findings highlight the potential of CsPWA-supported carbon catalysts as cost-effective and environmentally friendly systems for biodiesel downstream processing, contributing to waste-to-value strategies and promoting the development of a circular bioeconomy.