V-Cu composite oxide catalyst for transesterification of dimethyl carbonate with phenol to diphenyl carbonate

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 with a V/Cu molar ratio of 4/1. Under the conditions of 150 similar to 180 degrees 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 V2O5 and CuV2O6 at V/Cu = 4/1. Both crystalline V2O5 and CuV2O6 were the active phase. In addition, the activity of the catalyst 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 degrees C in air for 5 h, and the catalytic activity of the regenerated catalyst was almost as high as that of the fresh sample.