Promotional Effect of Alkali Metals on Activated Carbon Catalyst for Hexane Dehydrocyclization and 1-BOtene Isomerizat i o n

Abstract

The differences in promotional effect of alkali metals on; activated carbon catalyst for hexane dehydrocyclization and 1-butene isomerization were investigated. The dehydrocyclization activity increased as the ionic radius of alkali metal decreased and a large increase in activity was observed in the case of Na. Li and Na showed almost the same magnitude of the promotional effect. It was presumed that when Li or Na hydroxide was 'impregnated, active sites for the dehydrocyclization, probably radical sites, we1e formed by an interaction between the alkali metal and functional groups on the carbon. On the other hand, the addition of hydroxides of K, Rb and Cs primarily resulted in a formation of basic sites, on which 1butene was isomerized to 2-butene with a high cisltrans ratio.