Direct synthesis of diphenyl carbonate with heterogeneous catalysis reactionIX effect of Ce loading methods on catalytic activity of catalyst

Supported Pd-Sn-Ce catalysts for direct synthesis of diphenyl carbonate (DPC) were prepared with three different Ce loading methods that were sol-gel,co-calcination and precipitation methods.The characterization of the catalysts prepared with different Ce loading methods were investigated by XRD and TPR respectively,and the results showed that the main crystal phases in the different catalysts were all La 0.62 Pb 0.38MnO 3.But CeO 2 and Ce XSn 1-xO 2 were also detected in the catalyst prepared by sol-gel method;CeO 2 and SnO 2 were identified in the catalyst prepared by co-calcination method and CeO 2 was discovered in the catalyst prepared by precipitation method, too.Specific surface areas of catalysts prepared with different Ce loading methods were determined by SEM and specific surface area instrument, the results showed the S BET of catalyst prepared by sol-gel method was larger than that of the others.The synthesis of DPC was carried out and it was found that the activity and life of catalyst prepared by sol-gel was better than that of the others.Furthermore,optimization of synthesis conditions for different catalysts was also carried out respectively.