PROCESS FOR THE PREPARATION OF AN OLEFINIC PRODUCT

摘要

Process for the preparation of an olefinic product, comprising reacting an oxygenate feedstock comprising oxygenate species having an oxygen-bonded methyl group and an olefinic co-feed, in the presence of an oxygenate conversion catalyst comprising a molecular sieve having one-dimensional 10-membered ring channels, to prepare an olefinic reaction effluent, wherein the olefinic co-feed comprises less than 10 wt % of C5+ hydrocarbon species; fractionating the olefinic reaction effluent to obtain at least a light olefinic fraction comprising ethylene, and a heavier olefinic fraction comprising C4 olefins and less than 10 wt % of C5+ hydrocarbon species; recycling at least part of the heavier olefinic fraction; and withdrawing at least part of the light olefinic fraction as olefinic product.