Skeletal Isomerization of 1-Butene on MCM-22 Zeolite Catalyst

Catalytic cracking of 1-butene to propene and ethene on MCM-22 zeolite

“…1. It fits the typical crystalline MCM-22 phase similar to the diffraction peaks reported previously [12,13].…”

“…7.15% propene was also produced by other intermediates than [C 8 ] + carbenium intermediate (since the change of ethene yield was rather small in the range, the increase of the two values must be mainly due to the increment of propene yield). For example, [C 12 ] + (trimerization of butene) can be formed in the large pores of MCM-22 zeolite [13] and then cracked to propene and other small molecular hydrocarbons. C 6 and C 7 aliphatic hydrocarbons may be just the products of [C 12 ] + cracking, since they were initially very low at ca.…”

“…The performance of MCM-22 was also compared with that of a high silica ZSM-5 zeolite under similar conditions. It has been found that isomerization will simultaneously occur on MCM-22 with cracking reactions and other secondary reactions [13]. For simplicity, we group all the types of butene as the feed; the conversion is defined as: conversion = (C 4 H 8 % in the feed À C 4 H 8 % in the products)/(C 4 H 8 % in the feed).…”

“…[13] and using hexamethylene imine (HMI) as template. The molar composition of the gel: SiO 2 :Al 2 O 3 :Na 2 O:HMI:H 2 O is equal to 1:0.033:0.11:0.35:0.45.…”

“…Asensi et al [13] have studied isomerization of 1-butene to isobutene on MCM-22 zeolite under various operating conditions; they discussed the mechanisms of formation of isobutene and by-products from 1-butene on MCM-22 zeolite. In this work, we investigated the performance of MCM-22 zeolite in catalytic cracking of 1-butene to propene plus ethene under a wide range of operating conditions, i.e.…”