Alkylation—Chemistry and Fundamentals

Abstract

Alkylation of isobutane and aromatics have been performed commercially using liquid catalysts for many years to produce the following: high quality gasolines and alkyl benzenes (including ethyl benzene, cumene, and intermediates for detergents). Liquid–liquid dispersions or liquid–gas systems are used which contain protonic acids or Friedel–Crafts compounds as catalysts. The chemistry, which is always complicated, is reviewed to explain formation of the main products and by‐products. Different catalysts often result in significantly different chemistry. Fewer details are available on the following: relative kinetics of competing and simultaneous reactions plus physical phenomena affecting the overall processes. The ionic reactions generally occur at or near the interfacial areas between phases (often the catalyst and hydrocarbon phases). Mass transfer steps are often, if not always, of major importance. Recent information on the physical steps is discussed.