Monofunctional Platinum Research Articles

Isomerization and dehydrocyclization of hexanes over monofunctional supported platinum catalysts

This paper deals with a study of the isomerization and dehydrocyclization reactions of hexanes in the presence of inert-alumina-supported platinum catalysts. The activities for these reactions per exposed metal atom were found to be independent of the metal crystallite size, at least in the range of from 15 to 50 Å. It was also shown that five-membered ring structures, which are intermediates in the monofunctional platinum isomerization, are not involved in the conversion of n-hexane into benzene. Five-membered and six-membered ring closure of n-hexane are parallel reactions. The dehydrocyclization of n-hexane to benzene proceeds along two different routes: (i) by a platinum-catalyzed six-ring closure; (ii) by a thermal six-ring closure of hexatrienes formed by dehydrogenation of n-hexane over the platinum function.