| Diphenyl Carbonate (DPC), an important aromatic carbonate, is indispensable to produce polycarbonate using non-phosgene processes, which is a pollution-free and environmental benign method.In our previous study, Pd catalyst loaded on perovskite oxides was found to synthesize DPC with high activity by oxidative carbonylation method. Based on the previous study, the catalyst system was optimized. The reactor and synthesis route were also developed. In this paper, experimental data and model were provided, which served for industrialization of the production of diphenyl carbonate with heterogeneous catalysts. The main conclusions were as follows:1. It was found that the single phase perovskite La0.5Pb0.5MnO3 can be formed with lower baking temperature in the citrate process. The larger specific surface areas and the smaller crystal size were formed at lower calcination temperature. When the chelation occurred at pH<3 and the carrier calcinated in 800℃, it can be obtained with single-phase perovskite and large specific surface areas. The loaded catalyst has high activity for synthesis of DPC.2. When the amount of substituting atom is one tenth that of to be substituted atom. The supported Pd catalyst with lattice defect has better catalytic activity.3. The conditions for preparation of perovskite carrier by microwave calcination are as following:chelating reaction time 8 h,pH value 1.5,microwave calcination time 15 min. The phase of prepared carrier and the activity of catalyst are same as those of prepared by calcination.4. In the same condition, the DPC yield with semi-batch reaction is higher than that with batch reaction over supported Pd-Cu bimetal catalyst. The optimum reaction conditions are as follows: m(catalyst)=1g, m(phenol)=50g, Q(O2)=6mL/min, Q(CO)=115mL/min, pressure=1.0MPa, Temperature=80℃, reaction time 4h. The yield of DPC is 16.4%. The catalyst can be separated easily and recycled.5. The influence of catalyst molding condition on the catalyst performance...
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