Synthesis of dipropyl carbonate by transesterification on KNO3/MCM-48

The catalytic performance of KNO3/MCM-48 catalysts for the synthesis of dipropyl carbonate (DPC) by transesterification of dimethyl carbonate (DMC) and propanol was investigated. The catalysts were characterized by X-ray diffraction (XRD), FT-IR spectroscopy, N-2 adsorption and X-ray fluorescence. XRD results indicated that the intensity of characteristic peaks of MCM-48 was gradually reduced with the increase of K loading in KNO3/MCM-48, but the MCM-48 structure was still remained. IR spectra showed that KNO3 was gradually decomposed into K2O with increasing calcination temperature. The relative high catalytic activity and selectivity were obtained by changing the K loading and the reaction conditions. Under the optimized reaction conditions of reaction temperature 363 K, reaction time 6 h, catalyst dosage 5% and propanol/DMC molar ratio 4, the conversion of DMC was about 99.9%, the selectivity for DPC was 93.4%, and the yield of DPC reached 93.3% by using a catalyst with 15% K loading and calcined at 823 K.