Dehydration of methanol to dimethyl ether using catalysts based on a zeolite supported on silicon carbide

Patent metadata

Field	Value
Publication number	US-9073837-B2
Application number	US-51819607-A
Country	US
Kind code	B2
Filing date	Dec 7, 2007
Priority date	Dec 8, 2006
Publication date	Jul 7, 2015
Grant date	Jul 7, 2015

Abstract

A process for the preparation of dimethyl ether by catalytic dehydration of methanol, in which there is used a catalyst based on a zeolite immobilized on a silicon carbide support, for example a zeolite of type ZSM-5 supported on silicon carbide extrudates or on a silicon carbide cellular foam.

First claim

The invention claimed is:

1. A process for preparing dimethyl ether, comprising:
providing a catalyst comprising a zeolite immobilised on a silicon carbide support, the support comprising a rigid cellular foam; and
catalytically dehydrating methanol utilizing the catalyst.

2. The process of claim 1 , wherein the silicon carbide support has a specific surface area greater than 2 m 2 /g.

3. The process of claim 1 , wherein the zeolite is an MFI-type zeolite.

4. The process of claim 1 , wherein the zeolite is based on an aluminosilicate having a molar ratio Si/Al of from 20 to 100.

5. The process of claim 1 , wherein the zeolite is a ZSM-5 zeolite.

6. The process of claim 1 , wherein the silicon carbide support comprises silicon carbide of beta structure (β-SiC) in an amount of at least 80% by mass, based on total mass of the support.

7. The process of claim 1 , wherein the silicon carbide support comprises a mixture of silicon carbide of alpha structure (α-SiC) in admixture with silicon carbide of beta structure (β-SiC).

8. The process according to claim 7 , wherein the mass ratio α-SiC/β-SiC is from 1:99 to 50:50.

9. The process of claim 1 , wherein the rigid cellular foam has pore sizes of from 300 to 5000 microns.

10. The process of claim 1 , wherein the rigid cellular foam comprises β-SiC.

11. The process of claim 1 , wherein the silicon carbide support has a specific surface area of from 5 to 50 m 2 /g.

12. The process of claim 1 , wherein the zeolite is in a form of a layer having an average thickness of from 1 to 50 microns.

13. The process of claim 1 , wherein the catalytic dehydration of methanol is conducted at a temperature of from 200° C. to 500° C.

14. The process of claim 1 , wherein the catalytic dehydration of methanol is conducted at a temperature of from 220° C. to 350° C.

15. The process of claim 1 , wherein the catalytic dehydration of methanol is carried out under a pressure of from 1 to 50 bar.

16. The process of claim 1 , wherein the catalytic dehydration of methanol is carried out under atmospheric pressure.

17. The process of claim 1 , wherein the catalytic dehydration of methanol is carried out with an hourly space velocity of from 1 to 20 h −1 NTP.

18. The process of claim 1 , wherein the methanol used in the catalytic dehydration is substantially free of impurities.

19. The process of claim 1 , wherein the methanol used in the catalytic dehydration comprises methanol in admixture with other compounds and/or impurities.

Assignees

• Ivanova Svetlana
• Vanhaecke Estelle
• Libs Suzanne
• Louis Benoit
• Pham-Huu Cuong
• Ledoux Marc Jacques Marie
• Centre Nat Rech Scient
• Univ Pasteur

Inventors

• Ivanova Svetlana
• Vanhaecke Estelle
• Libs Suzanne
• Louis Benoit
• Pham-Huu Cuong
• Ledoux Marc Jacques Marie

Classifications

• C07C41/09 Primary

  by dehydration of compounds containing hydroxy groups · CPC title

• C07C43/043

  Dimethyl ether · CPC title