Catalytic performance of quaternary ammonium salts in the reaction of butyl glycidyl ether and carbon dioxide

The synthesis of cyclic carbonate from butyl glycidyl ether (BGE) and carbon dioxide was performed in the presence of quaternary ammonium salt catalysts. Quaternary ammonium salts of different alkyl group (C3, C4, C6 and C8) and anions (Cl−, Br− and I−) were used for this reaction carried out in a batch autoclave reactor at 60–120 °C. The catalytic activity increased with increasing alkyl chain length in the order of C3 < C4 < C6. But, the quaternary ammonium salt with longer alkyl chain length (C8) decreased the conversion of BGE because it is too bulky to form an intermediate with BGE. For the counter anion of the tetrabutyl ammonium salt catalysts, the BGE conversion decreased in the order Cl− > Br− > I−. The effects of carbon dioxide pressure and reaction temperature on this reaction were also studied to better understand the reaction mechanism.