Synthesis of cyclohexyl acetate catalyzed by rare earth composite solid superacid SO_4~(2-)/TiO_2/Sm~(3+) under microwave irradiation

The acylation of cyclohexanol with acetic anhydride was studied with rare earth composite solid superacid SO2-4/TiO2/Sm3+ as heterogeneous catalyst under microwave irradiation.The effects of different factors such as catalyst dosage,mole ratio of reactants,microwave irradiation power and microwave irradiation time on the yield of cyclohexyl acetate were carefully investigated.The experimental results showed that rare earth composite solid superacid SO2-4/TiO2/Sm3+ exhibited excellently catalytic activity.The best reaction conditions were as follws:when the amount of acetic an-hydride was 0.1mol,the ratio of cyclohexanol to acetic anhydride was 2.4∶1.0,the dosage of catalyst was 1.0% of the total mass of the reactants,microwave irradiation power 385W and radiation time 15min.Under these conditions,the yield of cyclohexyl acetate could be reach 95.3%.The catalyst could be repeatedly used six times without lossing its catalytic.The product was colorless,transparent and provided with high purity.The product was characterized by refractive index and infrared spectra.