Unsteady state simulation and process design of a batch reactive distillation column with multiple side reactors for benzyl chloride production

A batch distillation column coupled with multiple side reactors was established to produce benzyl chloride through toluene chlorination, and its unsteady state process was simulated using Aspen Plus. The influences of reactor number, extraction ratio, extraction position, chlorine distribution, distillation time and boil-up ratio on the performance of batch reactive distillation were investigated. The simulation results indicate that the best match between reaction and separation can be achieved, and the optimal parameters are as follows: column tray 8, side reactor number 2, chlorine distribution 7:3, 85% of the liquid flow extracted from the 3^rd stage into the 2^nd reactor and boil-up ratio 25 kmol·h^-1. Under the optimum conditions, 50 kmol toluene can be converted to benzyl chloride in 9 h with both conversion and selectivity up to 98.0%.