| Diphenyl Carbonate(DPC),which is a chemical material mainly used to produce Poly-Carbonate in polyester industry, has been of great interest to prepare DPC with safer process and lower cost. In recent years, a direct oxidative carbonylation method for DPC synthesis has been paid more attention as it involves only one single step reaction. In the literature, oxidative carbonylation method for DPC synthesis uses homogeneous catalytic reaction. In the case, it is not easy to scale up the process due to problems of product separation and catalyst recovery. In order to solves the problems posed by homogeneous catalytic reaction, the heterogeneous catalytic technology for DPC synthesis has been proposed in the paper and investigation have been carried out as following:Screening of carriers was conducted and the result showed that the compound metal oxide LaxPbyMnOz carrier was better for DPC synthesis than others.Preparation processes of compound metal oxide LaxPbyMnOz carrier and Pd supported catalyst were studied, the results revealed that when the support was prepared by sol-gel method and under the conditions of calcining temperature 800℃ , Lanthanum–loading content 9.32 wt%, mass ratio of citric acid and total metal ion 1 to1, and the active component was loaded by precipitation with Na2PdCl4 as active substance and NaOH as precipitating agent, the catalyst showed a higher catalytic activity. The optimizing of synthesis conditions was determined by orthogonal experiments and the experimental results showed that reaction temperature was the first factor of effect on the selectivity and yield of DPC, and the concentration of O2 in gas phase also has significant effect on selectivity of DPC. The optimum reaction conditions were that catalyst/phenol mass ratio 1 to 50, pressure 4.5 MPa, the volume concentration of O2 25%, the reaction temperature 60℃ and the reaction time 4 h. d. The improvement of catalyst was also tested by loading Sn and Ce , results showed that when the co-active component Sn was added in Pd/ LaxPbyMnOz by co-calcination method and its loading content was equal to 14.43%, the yield and selectivity of DPC could reach 26.78% and 99% respectively, which were higher than the values reported in the literatures; and that the promoter Ce was loaded by gel-sol method and its loading content was equal to 5%, the promoter could benefit to improve the life of Pd-Sn catalyst. Deactivation and regeneration were characterized by ICP, XPS and SEM, results showed that Sn and other element migrating from inside surface to out surface of catalyst with reaction time led to the deactivation of the catalyst. e. The new instrument of measuring gas solubility was designed, and the solubility of carbon monoxide, oxygen and other gases in phenol and carbon monoxide, oxygen in phenol-tertrabutylamonium binary solvents were measured respectively under the temperature in range of 55℃ to 95℃ and gas pressure in range of 1.0 to 8.00MPa, the results showed that solubility of carbon dioxide were decreased with temperature increasing, but others were increasing; the solubility of carbon monoxide rises up with the content of tertrabutylamonium in mixing solvent increasing ,but the change trend of solubility for oxygen was reverse . By using the regular-solution theory and the virial expansion for the Redlich-Kwong equation of state, an equation was proposed to relate the solubility of the gases in the non-volatile solvent to temperature and pressure. The results revealed the equations used to correlate high-pressure gas solubility of oxygen and carbon monoxide and other gas in phenol at various temperatures were accurate. f. Kinetic experiments of DPC synthesis with heterogeneous catalytic technology in batch reactor were carried out preliminary and kinetic equations were proposed. When the reaction temperature was in range of 323K to 343K, it was ' '; when the reaction temperature was in range of 347K to 353K, it was ' '.
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