Synthesis of glycerol carbonate from glycerol and CO2 over Cu/In2O3/ZnO nanostructured catalyst

Abstract

The excess glycerol generated as a by-product in the biodiesel sector has intrigued researchers to explore the catalytic pathways for the transformation of this platform molecule to value-added components, such as glycerol carbonate. In the present investigation, Cu/In₂O₃/ZnO catalyst with variable Cu loading was synthesized utilizing a conventional precipitation technique. The resultant catalyst was employed for direct carbonation of glycerol using CO₂ for the production of glycerol carbonate. The incorporation of Cu into the In₂O₃/ZnO system contributed significantly in improving the catalytic property of the material. The impact of various reaction parameters, including the presence of dehydrating agent, reaction temperature, time, and CO₂ pressure on the resultant product of the reaction was systematically assessed. Under the optimized reaction conditions of 150 ºC temperature, 5 h reaction time, 5 MPa CO₂ pressure, and 30 mmol of 2-cyanopyridine, the maximum yield of glycerol carbonate recorded was 24.32 %. Catalyst’s heterogeneity was confirmed using Sheldon’s hot filtration test.