Transesterification of dimethyl carbonate with phenol to diphenyl carbonate over V2O5 catalyst

A novel heterogeneous catalyst, pure V2O5 catalyst prepared by calcination of NH4VO3 at 550 °C in air, was used for the synthesis of diphenyl carbonate (DPC) by the transesterification of dimethyl carbonate (DMC) with phenol. The effects of V2O5 amount, reaction time and molar ratio of dimethyl carbonate to phenol were investigated. Under the conditions of mass fraction of catalyst 1.6%, molar ratio of DMC/phenol of 1.5:1 and a reaction time 9 h, the maximum conversion of phenol and total yields of methyl phenyl carbonate (MPC) and DPC were 42.0 and 40.1%, respectively. Reuse of the catalysts revealed an appreciable deactivation. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform-infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM) characteristics of the fresh and used catalyst samples had been recorded. The results showed that the deactivation of the catalyst was mainly ascribed to the conversion of crystal structure. Moreover, the deactivated catalyst could be easily reactivated by calcination in air, and the regenerated catalyst showed the catalytic activity almost as high as that of the fresh sample. However, a small difference in catalytic activities between regenerated and fresh catalysts was possibly owing to the sintering of the regenerated catalyst.

Pure V2O5 catalyst was used in the transesterification of dimethyl carbonate with phenol. It was found that the fresh V2O5 catalyst had highly initial activity for the reaction and the deactivation of the catalyst was mainly ascribed to the conversion of crystal structure. However, the catalytic activity and catalyst structure could be recovered by calcination of the used catalyst in air.Figure optionsDownload as PowerPoint slide