Optimum design of a column/side reactor process

One of the limitations for reactive distillation to be economically attractive is that the temperature range suitable for reasonable chemical reaction kinetics must match the temperature range suitable for vapor-liquid equilibrium because both separation and reaction occur in a single vessel. This temperature mismatch problem can sometimes be overcome by considering an alternative process flowsheet that features a distillation column linked with several external side reactors. The column operates at a low pressure and temperatures favorable for separation. Liquid sidestreams from trap-out trays at intermediate locations in the column are pumped to external reactors operating at higher pressure and temperatures that are favorable for chemical kinetics. This paper extends our previous work [Kaymak, D. B.; Luyben, W. L. Ind. Eng. Chem. Res. 2004, 43, 8049-8056] to provide a more rigorous steady-state economic optimization of the column/side reactor flowsheet. Results demonstrate that this configuration has better steady-state economics than conventional reactive distillation in cases where there is a temperature mismatch between reaction and separation.