Alkylation of Benzene with Propylene Catalyzed by Ionic Liquids

1. Introduction The alkylation of benzene with propylene produces cumene, a very important petrochemical feedstock used for the production of phenol and acetone (Yang, 1990). More than 90% of the global phenol demand is derived from cumene. Hence, the growth rate of cumene production is closely associated with that of phenol. Cumene demand is expected to grow by about 3.5% annually over the next 5 years (Kleinloh, 1997). The global cumene capacity from some 40 plants worldwide is about 8 mil…

Alkylation of Benzene with Propylene Catalyzed by Ionic Liquids

The alkylation of benzene with propylene catalyzed by ionic liquids to obtain cumene was investigated. Propylene conversion and cumene selectivity under mild reaction conditions were improved greatly after the ionic liquid was modified with HCl. Under the conditions of 20 oC, 0.1MPa, 5 min of reaction time, and a molar ratio of benzene to propylene of 10:1, propylene conversion increased from 83.6% to 100%, and cumene selectivity increased from 90.86% to 98.47%. In addition, it was found that the reaction could be carried out in two different stages so as to obtain a better result. At the first stage, the key reaction was alkylation and a higher propylene conversion was obtained at a lower temperature;At the second stage, the key reaction was transalkylation and a higher temperature was used to improve cumene selectivity. The reaction temperature, pressure and the amount of catalyst used in this work were lower than those used in traditional alkylation processes.