Modeling and Optimizing of Cumene Synthesis Using Zeolite-Catalyzed Alkylation

This study focused on simulating and optimizing the production of cumene (iso-propylbenzene) through the alkylation of benzene with propylene using a Beta Zeolite catalyst. Two process configurations were evaluated: one without a transalkylation reactor and another incorporating a transalkylation unit to convert byproducts back into cumene. The process was modeled under steady-state conditions in Aspen HYSYS using plug flow reactors and the Peng-Robinson fluid package, with reaction kinetics derived from literature on zeolite-catalyzed systems. Optimization studies examined the effects of reactor temperature, pressure, and benzene-to-propylene molar ratio. In-creasing the reactor temperature to 178°C improved propylene conversion to 96.20%, while raising the pressure from 3540 kPa to 3600 kPa further enhanced conversion to 96.24%. Cumene production was enhanced to 135.792 kmol/h while minimising by-product formation by optimising the benzene-to-propylene molar feed ratio to about 0.75:1. The original fresh benzene feed flow rate was 127.7 kmol/h, which was reduced to 101 kmol/h. According to a comparison analysis, the setup without a transalkylation reactor generated 4.171 kmol/h of diisopropylbenzene (DIPB) as waste, which posed a risk to the environment because of its toxicity as well as financial losses. On the other hand, DIPB conversion into more cumene was made possible by the transalkylation reactor, which increased process sustainability and efficiency. These results show that adding a transalkylation step and optimising reaction parameters including tempera-ture, pressure, and input ratios greatly increases cumene yield while lowering waste production, resulting in a more practical and sustainable process.