Production of glycerol carbonate from carboxylation of glycerol with CO2 using ZIF-67 as a catalyst

Abstract

Owing to the urgent demand for CO2 emission and the increasing need for the utilization of waste glycerol from biodiesel production, cobalt-based zeolitic imidazolate framework-67 (ZIF-67) was prepared as a catalyst for the carboxylation of glycerol to glycerol carbonate under different reaction conditions. ZIF-67 exhibited high crystallinity, a high specific surface area of ~1250 m2 g−1, promising thermal stability with a weight loss of ~10% above 400 °C, facile ligand-to-metal electron transition, and numerous Lewis basic sites, indicating its high catalytic activity. The conversion, yield, and selectivity achieved with ZIF-67 were 32, 29, and 92%, respectively, at reaction temperature and duration of 210 °C for 12 h, respectively. The catalytic gas–liquid reaction followed third-order kinetics. This is the first study to elucidate the reaction kinetics of glycerol carboxylation using ZIF-67 as a catalyst and to highlight the potential of ZIF-67 as a functional catalyst for CO2–glycerol conversion.