The Simulation And Optimization Of Methyl N-phenyl Carbamate Separation Process

Methyl N-phenyl carbamate (MPC) is an important organic intermediate, it was mainly used in the preparation of pesticide, medicine and isocyanate and other chemicals. The synthesis of intermediate MPC is the key step in the clean route synthesizedMethylene-4,4-diphenylisocyanate(MDI)by decomposition of methyl carbamate, which is different from the other routes. Nowadays, the routes for synthesis of MPC by alcoholysis of N,N'-diphenyl urea and the coupling route are likely to come true in the manufacturing production, which were produced many components involved MPC. The question how to get pure MPC is required to resolved urgently. According to the requirement of MPC, the separated system DMC-MPC-NAN-N,NAN and METHANOL-ANILINE-MPC were simulated by the chemical engineering simulation software ASPEN PLUS for two routes. The purpose is designed for appropriate separation technology. The main results are as follows:(1)The thermal decomposition temperature of MPC is determined by TG/DTG, confirmed that temperature is the key reason for separation.(2)The property of components of the route which came from coupled reaction is determined and calculated:experimented with vapor-liquid equilibrium data of DMC-MPC and calculated date of the other components. According to literature, the property method was chosen and separation project of series flash and distillate columns with side withdrawing was designed. Operating parameters were analysed by sensitivity analysis tool and optimized based on the least energy consumption. Under the feasible separation conditions, the mass fraction of MPC could be reached 99.00% and yield could be above 99.50%.(3)The property of components of the route for synthesis of MPC by alcoholysis of N,N-diphenyl urea is determined and calculated:experimented with vapor-liquid equilibrium data of Aniline-MPC and calculated date of the other components. According to literature, the property method was chosen and separation project of series-parallel four columns was designed. Operating parameters were analysed by sensitivity analysis tool and optimized based on the least energy consumption. Under the feasible separation conditions, the mass fraction of MPC could be reached 99.00% and yield could be above 99.50%.(4)The separation equipment was designed, fixed and debugged. Utilized this equipment to experiment the separated production which came from different reaction routes. And the results showed that the separation project mentioned above could be matched the separation request of MPC. The mass fraction of MPC obtained could be reached 98.00% and yield could be above 99.50%.(5)Compared of energy consumption of the two routes and cleaned up the process package for the route of synthesis of MDI through coupled reaction, concerning the workshop section of DPU and MPC.