Synthesis of glycerol carbonate via heterogeneous catalysis for effective utilization of byproducts from plant oil-based biodiesel production

Aim. To establish the possibility of using heterogeneous catalysts of different nature (based on carbon (graphene oxide), polymer (PEO/PEI) and oxide systems (Fe2O3/Al2O3, Сo3O4/Al2O3 and NiO/Al2O3)) in the catalytic conversion of glycerol with carbon(IV) oxide for the effective use of by-products of vegetable oil-based biodiesel production. Methods. Synthesis of glycerol carbonate via heterogeneous catalysis, gas chromatography, mass spectrometry. Results. It was shown that the reaction of glycerol with carbon(IV) oxide in the presence of heterogeneous catalysts is possible only under conditions of elevated temperatures and pressures and in the presence of a dehydrating agent (acetonitrile). It was established that the catalytic activity significantly depends on the chemical nature and stability of the materials, with the highest glycerol conversion (21.9%) provided by the NiO/Al₂O₃ catalyst, and the highest yield of carbonate products (2.34%) achieved when using the PEO/PEI polymer catalyst. Conclusions. The results obtained indicate the prospects for the use of heterogeneous catalysts in the processes of glycerol and CO₂ utilization and can be the basis for further optimization of the catalyst composition and reaction conditions in order to increase the selectivity and yield of glycerol carbonate as a valuable substance.