Simulation and Optimization of the Phosgenation Reactive Distillation
Process for Producing Toluene Diisocynate
Toluene diisocyanate (TDI) is an important chemical intermediate
prepared by phosgenation reaction between toluene diamine and phosgene
with two steps name cold and thermal phosgenation respectively. In this
paper, the reactive distillation model for the thermal phosgenation
reaction based the kinetics equations was established for an industrial
installation, and the effects of the different parameters on the process
performance were studied firstly; then based on the analysis results, a
thermal coupling process between the towers of reactive distillation and
phosgene purification was presented and investigated; finally, the
optimal operation scheme was simulated and the results showed that the
proposed process can save the heat and cold energy with 7.29% and
32.78%, respectively, and reduce the total annual cost about 17.11%.
The result of the paper can be used to guide the operation configuration
or the revampment of the TDI production equipment.