Effects of Isobutylene on Isobutane Isomerization over H-Mordenite

Abstract

Reaction kinetics studies were conducted of isobutane conversion over H-mordenite at 473K using a system comprised of two reactors connected in series. The first reactor was loaded with Pt/Sn catalyst and controlled the olefin concentration in the feed to the second reactor containing H-mordenite by varying the dehydrogenation–hydrogenation equilibrium between butanes and butenes. The presence of isobutylene increases the rate of isobutane isomerization and increases the rates of side reactions such as coking and oligomerization/β-scission processes which lead to C3, C5, and C6products. The kinetic data for the production of C3, C4, C5, and C6species were described by a kinetic model involving olefin adsorption/desorption, oligomerization/β-scission, and hydride transfer steps. The rates of oligomerization/β-scission steps involving C4species are faster than the rates of hydride transfer for our reaction conditions.