Process for preparing an epoxide from an oxygenate

摘要

The invention relates to an integrated process for preparing an epoxide from an oxygenate, wherein the oxygenate is converted into a lower olefin and the lower olefin is subsequently epoxidised, and wherein isobutane obtained after hydrogenation and subsequent normal/iso separation of C4 hydrocarbons obtained as by-product of the oxygenate conversion, is converted into a hydroperoxide that is used for the conversion of the lower olefin into the corresponding epoxide.

主权项

1. A process for preparing an epoxide from an oxygenate, the process comprising the following steps:
a) contacting the oxygenate with a molecular sieve-comprising catalyst, at a temperature in the range of from 350 to 1000° C. to obtain an olefinic product stream comprising ethylene, propylene and C4 hydrocarbons; b) separating ethylene and/or propylene and a fraction comprising C4 hydrocarbons including normal butane, isobutane, normal butene and isobutene, from the olefinic product stream; c) hydrogenating at least part of the fraction comprising C4 hydrocarbons in a hydrogenation unit to obtain a saturated C4 hydrocarbon stream; d) separating the saturated C4 hydrocarbon stream into a stream enriched in normal butane and a stream enriched in isobutane; e) oxidizing the isobutane in the stream enriched in isobutane into tertiary butyl hydroperoxide; and f) reacting tertiary butyl hydroperoxide obtained in step d) with ethylene and/or propylene separated from the olefinic product stream obtained in step a) to obtain the epoxide and tertiary butanol.