Process for preparing C2- to C4- olefins from a feed stream comprising oxygenates and steam

US8785708B2 · kind B2 · utility

Assignee

• Lurgi GmbH · DE

Inventors

• Martin Rothaemel · Frankfurt am Main, DE
• Walter Boll · Frankfurt am Main, DE
• Gerhard Birke · Frankfurt am Main, DE
• Harald Koempel · Neu-Isenburg, DE
• Waldemar Liebner · Oberursel, DE
• Hermann Bach · Heiligenroth, DE

Key dates

• Filing date: Feb 28, 2006
• Grant date: Jul 22, 2014
• Expiry date: Jun 21, 2030

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P30/40
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

In a process for the preparation of C2- to C4-olefins, a feed stream comprising oxygenates and steam is passed through at least one fixed-bed zone comprising zeolite catalyst, where the oxygenates are converted catalytically into olefins with high selectivity for lower olefins, and the reaction mixture leaving the fixed-bed zone is separated into a first product stream comprising C2- to C3-olefins and inert gas components, at least one second product stream comprising C4+-olefins, and a third product stream consisting of aqueous phase. In order to improve the yield of lower olefins, the aim is to regulate the temperature of the catalytic reaction in accordance with a target temperature value in the range from 440 to 520° C. specified for the reaction mixture exiting the fixed-bed zone by means of a supplementary stream consisting of olefins and inert gas components fed into the feed stream.