KINETICS OF ISOBUTANE DEHYDROGENATION OVER PLATINUM-ALUMINA CATALYSTSIN THE PRESENCE OF WATER-VAPOR

The kinetics of isobutane dehydrogenation to isobutylene over platinum -alumina catalysts modified with potassium, tin, and indium was studie d in the presence of hydrogen and water vapor. The kinetic equation fo r the reaction proceeding over these catalysts was derived. It was fou nd that the introduction of tin and indium led to an increase in the r ate and selectivity of dehydrogenation and to the catalyst stability, isobutylene reduced the retardation of the reaction, whereas water vap or favored it. Potassium improved the catalyst stability. Water vapor, on the one hand, decreased the fraction of isomerization and coke for mation, and, on the other hand, favored the occurrence of oxidation re actions.