V–Cu Composite Oxide Catalyst for Transesterification of Dimethyl Carbonate with Phenol to Diphenyl Carbonate

Abstract The V–Cu composite oxide catalyst was prepared by coprecipitation and used for the synthesis of diphenyl carbonate (DPC) by transesterification of dimethyl carbonate (DMC) with phenol. The effect of the molar ratio of V:Cu and the reusability of the catalyst were investigated. The catalyst showed the highest activity at a V:Cu molar ratio of 4:1. Under the conditions of 150–180°C and 9 h, the conversion of phenol and the transesterification selectivity over the V–Cu catalyst were 37.0% and 96.8%, respectively. According to the X-ray diffraction results, the V–Cu composite oxide was composed of crystalline V 2 O 5 and CuV 2 O 6 at V:Cu = 4:1. Both crystalline V 2 O 5 and CuV 2 O 6 were the active phase. In addition, the catalyst activity was reduced from 37.0% to 23.7% after the catalyst was reused three times. However, the used catalyst could be easily regenerated by calcination at 550°C in air for 5 h, and the catalytic activity of the regenerated catalyst was almost as high as that of the fresh sample.