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The phenyl carbamate (MPC) is an important chemical intermediates of the synthesis of isocyanate . The synthesis of isocyanate polyurethane has excellent performance and features the higher resistance variability, stability , strength , high abrasion resistance , high tear strength , low temperature flexibility and chemical stability , widely used in plastic , rubber , fiber , paint , exclusion of agents , and other areas of high value and prospects . For the synthesis of the amino acid methyl ester ( MC ) urea , carbamate and then reacted with aniline (AN) for the synthesis of phenyl carbamate is a very promising clean synthesis route . Methanol , urea and aniline as raw material , the use of heterogeneous metal oxide process for the catalytic synthesis of benzene carbamate . First, based on zinc oxide as the catalyst , urea, and methanol as a process for the catalytic synthesis of methyl carbamate reaction . Were investigated by experiments the raw material molar ratio, reaction temperature , reaction pressure, the amount of the amount of catalyst , a coupling agent , reaction time and other factors on the reaction yield . The results show that : the raw material for this reaction the optimum molar ratio of methanol: urea = 1:9, and the reaction temperature is 15 ℃, the optimal reaction pressure was 1.3MPa , the optimum amount of catalyst is 0.5% of the quality of urea , the most good amount of coupling agent for 40% of the urea quality , best reaction time of 2 h , the MC yield up to 57.00% under optimal conditions . Secondly, the paper by methoxy lead as catalyst, aniline and carbamate synthesized phenyl carbamate reaction influences the amount of the solvent , temperature , time , amount of catalyst , and the ratio of raw materials and other conditions on the synthesis reaction the impact . The results show that : the optimum reaction conditions for this reaction as a solvent methanol dosage m (methanol) / m ( MC ) = 2 , the reaction temperature of 150 . C , reaction time 5h, the amount of catalyst mass fraction (% of total raw materials ) 0.35% , the ratio of raw materials m ( MC ) / m (AN ) = 2 . Under optimum conditions , the MPC yield up to 97.5% , the selectivity of 97.86% .
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