An basic ionic liquid 1-methyl-3-(triethoxysilyl)propylimidazolium hydroxide ([Smim]OH) were grafted on mesoporous silica gel (SiO2) with different amount by post-grafting method. The prepared materials
which were verified by means of FTIR
element analysis
29Si MAS NMR and TG could be used as heterogeneous catalysts toward propylene carbonate (PC) synthesis through cycloaddition of CO2 with propylene oxide (PO) under solventless and mild conditions. The results showed that such grafted ionic liquids (GILs) were successfully grafted on the support of silica gel via covalent bonds
but the degree of ionic liquids grafted on the silica gel was different. Under the optimal reaction conditions
the PO conversion could reach 99.5% and 100% selectivity towards PC. The catalyst could be recovered and recycled easily with filtration. In addition
the catalytic activity basically remained after being used for several times.