Activity of cation-exchange forms of an aluminosilicate catalyst in the skeleton isomerization of n-pentenes

Abstract

A promising way of using n-pentenes efficiently is to convert them into methylbutenes. The resources of n-pentenes in the petrochemical industry are fairly large. Natural and synthetic aluminosilicates, aluminium oxide modified with halogens, and halides of metals are of interest as promising catalysts for conversion of n-pentenes into methylbutenes. By varying the conditions of the process, on the indicated catalysts it is possible to obtain fairly high yields of methylbutenes (50-60% of the materials fed). However, practical utilization of halogen-containing catalysis is made difficult by the stringent requirements concerning drying of the fed material, and also by the need to reactivate the catalysts (by introducing a halogen) after oxidizing regenerations. Aluminosilicate catalysts (ASC) are not adversely affected by moisture in the fed material and are readily regenerated, but they are insufficiently selective. In the present work a study was made of the nature and strength of the acid centers of ASC on their activity and selectivity in skeletal isomerization of n-pentenes, and the possibility of obtaining an effective catalytic system by means of modifying and controlling the acid properties of ASC was demonstrated.