Study On The Synthesis Of Diphenyl Carbonate By Ultrasonic Enhancement

Along with social progress and increased awareness of environmental protection, peoplebegan to realize that the hypetroxic phosgene causes seirous pollution and phosgene process toproduce DPC can not meet the requests of modern green chemical industry development, itwill be destined to be replaced by the new environmental firendly process. Now the typicallynon-phosgene process is transcstcriifcation process.In the paper, a high effect homogeneous catalyst were studied. It was conformed by themain catalyst and co-catalyst, the main catalyst was a multi-metal composite catalyst with CI，Fc and Y metal oxides as its main component (metal molar ratio of: CI: Fe: Y=2:1:1.5). Thenew catalyst can withstand high temperature and has a long life. Not only dramaticallyincreased Catalytic effect But also suppressing the generation of by-product, the catalyst meetsindustiralized large-scale, continuous production characteristics.Through single factor experiment and orthogonal expeirment the transesterificationsynthesis process were optimized, the feed ratio of phenol: DMC was0.85:1，DMC droppingrate1.5ml/min, catalyst dosage3%, the reaction temperature is175"C, reaction time is12h,the reaction conversion is43.6%. by the introduction of ultrasonic irradiation In theconventional synthesis reaction the catalytic effect was enhanced, when the ultrasonic powerwas55%, the reaction conversion rate raised more than12%compared with withoutultrasound catalyzed, the target product-diphenyl carbonate was identified By NMR spectra，IR spectra, mass spectra. And the gas chromatography spectrum analysis results demonstratethat the purity is99.53%,Because of the reversible characteristics of MPC disproportionation reacti"on, the reversepreparation vacuum distillation purification" approach were adopted. Using DMC, DPC asraw materials，adjusting the operating parameters of the synthesis distillation，the optimumoperating parameters were established, when relfux ratio was2，the conversion rate increase2.67%. the operating parameters were optimized, reifned distillation tower prcssurc-0.093MPa,kettle temperature230"C，99.5%of the content of qualified products can obtained. The rangeanalysis shows that the process of DPC synthesis has high stability. The corrosion of the raw mateirals, products and by-products to the of304stainless steelwere veirifed, the adaptability of equipment and piping material of the process medium wereEnsured,...