Understanding the role of basicity in Al–Mg pillared bentonite catalysts for the conversion of glycerol into valuable chemicals

Abstract The valorization of glycerol, a major byproduct of biodiesel production, into valuable chemicals is a crucial step toward sustainable biorefinery processes. Glycerol carbonate, propylene glycol, and propylene carbonate, along with other derivatives, show strong potential as eco‐friendly solvents, polymer precursors, and intermediates in green chemistry applications. This study investigated the influence of catalyst basicity on the efficiency and selectivity of glycerol conversion using Al–Mg pillared bentonite catalysts. Catalysts with Al/Mg molar ratios of 0.1, 0.3, 0.5, and 0.8 were synthesized via pillarization and characterized using thermogravimetric analysis (TGA), X‐ray diffraction (XRD), surface area analysis, and porosity measurements (N 2 adsorption), field emission–scanning electron microscopy (FE‐SEM), CO 2 ‐temperature programmed desorption (CO 2 ‐TPD), and Fourier‐transform infrared (FTIR) spectroscopy. Catalytic performance tests evaluated the impact of basicity on glycerol conversion and selectivity toward desired products. The results show that optimal basicity in pillared clay catalysts substantially improved glycerol conversion and selectivity toward propylene glycol, propylene carbonate, glycerol carbonate, and other compounds. The study highlights the satisfactory performance of an Al–Mg bentonite catalyst at an Al/Mg ratio of 0.5. Conversion rates and product yields in the one‐pot reaction remained moderate, however, exceeding 30% only. The presence of water in glycerol or the performance of Al–Mg bentonite catalyst were insufficient to support the transesterification reaction effectively, which may explain this limited outcome.