Membrane process for separating gases from gas-liquid charge streams

• US 4,897,091 A
• Filed: 04/04/1988
• Issued: 01/30/1990
• Est. Priority Date: 04/04/1988
• Status: Expired due to Fees

• Current Assignee: Texaco Incorporated (Chevron Corp.)
• Original Assignee: Texaco Incorporated (Chevron Corp.)
• Inventors: Beaupre, Richard F., Pasternak, Mordechai
• Primary Examiner(s): Spear, Frank
• Application Number:
  US07/176,895
• Time in Patent Office: 666 Days
• Field of Search: 210/500.37, 210/490, 210/640, 55/16, 55/158, 55/159
• US Class Current: 95/46
• CPC Class Codes: B01D 19/0031 by filtration
• CPC Class Codes: B01D 61/00 Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor separation of gases or vapours by diffusion B01D53/22
• CPC Class Codes: B01D 61/362 Pervaporation
• CPC Class Codes: B01D 61/364 Membrane distillation
• CPC Class Codes: B01D 69/125 In situ manufacturing by polymerisation, polycondensation, cross-linking or chemical reaction

Abstract

Gases such as carbon dioxide may be separated from rich liquor (such as methanol containing carbon dioxide) by passage of gas through a membrane which is the reaction product of (i) a polyamine and (ii) a polyisocyanate or a poly (carbonyl chloride).

Claims

1. The process for separating a gas from a gas-liquid charge which comprises

maintaining, as a non-porous membrane separating layer, a membrane of the polymeric reaction product of (i) a poly oxyalkylene polyamine and (ii) a dissocyanate;

passing into contact with the charge side of said membrane a gas-liquid charge;

maintaining a pressure drop access said membrane whereby at least a portion of said gas of said gas-liquid charge passes through said membrane as permeate and said gas-liquid charge is converted to a lean liquid retentate containing less gas than is present in said gas-liquid charge;

recovering from the low pressure side of said non-porous membrane separating layer said permeate gas; and

recovering from the high pressure side of said non-porous membrane separating layer said lean liquid retentate containing less gas than is present in said gas-liquid charge.

2. The process for separating a gas from a gas-liquid charge as claimed in claim 1 wherein said gas-liquid charge contains an acid gas.

3. The process for separating a gas from a gas-liquid charge as claimed in claim 1 wherein said gas-liquid charge contains carbon dioxide.

4. The process for separating a gas from a gas-liquid charge as claim 1 wherein said gas-liquid charge contains an alcohol.

5. The process for separating a gas from a gas-liquid charge as claimed in claim 1 wherein said gas liquid charge contains methanol.

6. The process for separating a gas from a gas-liquid charge as claimed in claim 1 wherein said gas liquid charge contains carbon dioxide and methanol.

7. The process for separating a gas from a gas-liquid charge as claimed in claim 1 wherein said polyamine is a diamine.

8. The process for separating a gas from a gas-liquid charge as claimed in claim 1 wherein said polyamine is a polyoxyalkylene triamine.

9. The process for separating a gas from a gas-liquid charge as claimed in claim 1 wherein said polyamine is an aromatic diamine.

10. The process for separating a gas from a gas-liquid charge as claimed in claim 1 wherein said polyisocyanate is an aromatic diisocyanate.

11. The process for separating a gas from a gas-liquid charge as claimed in claim 1 wherein said polyisocyanate is a m-phenylene diisocyanate.

12. A membrane comprising the polymeric reaction product of (i) a polyoxyalkylene polyamine and (ii) a diisocyanate.

13. A membrane as claimed in claim 12 wherein said polyamine is a triamine.

14. A membrane as claimed in claim 12 wherein said polyamine is:

##STR7## wherein x+y+z is 1-20.

15. A membrane as claimed in claim 12 wherein said diisocyanate contains an aromatic nucleus.

16. A membrane as claimed in claim 12 wherein said diisocyanate is a toluene diisocyanate.

17. A membrane comprising the polymeric reaction product of:

##STR8## wherein x+y+z is 1-20 and toluene diisocyanate.