Reactive distillation process for hydrolysis of esters

• US 20020077501A1
• Filed: 10/13/2001
• Published: 06/20/2002
• Est. Priority Date: 10/16/2000
• Status: Active Grant

• Current Assignee: Eastman Chemical Company
• Original Assignee: Eastman Chemical Company
• Inventors: Holcombe, Edwin Franklin III, Hoyme, Craig Alan
• Granted Patent: US 6,518,465 B2
• Time in Patent Office: Days
• US Class Current: 562/512
• CPC Class Codes: B01D 3/009 in combination with chemical reactions
• CPC Class Codes: C07C 41/01 Preparation of ethers
• CPC Class Codes: C07C 43/043 Dimethyl ether
• CPC Class Codes: C07C 51/09 from carboxylic acid esters or lactones
• CPC Class Codes: C07C 53/08 Acetic acid pyroligneous acid C10C; preparation of vinegar C12J
• CPC Class Codes: Y02P 20/10 Process efficiency

Abstract

A process for hydrolyzing an alkyl ester to produce a carboxylic acid product and an ether product, the process includes the steps of introducing into a reaction zone of a reactive distillation column a feed containing the alkyl ester wherein the reaction zone is at a temperature and pressure to preferentially produce an ether from the ester; and recovering the ether and the carboxylic acid.

Claims

1. A process for preparing a carboxylic acid from an alkyl ester comprising:

a. introducing said alkyl ester into a reaction zone of a reactive distillation column wherein said reaction zone is at a temperature and pressure to preferentially produce said carboxylic acid and an ether from said ester; and

b. recovering said ether and said carboxylic acid.

2. The process of claim 1 wherein said alkyl ester is hydrolyzed in said reaction zone

3. The process of claim 1 wherein said alkyl ester has from 1 to 3 alkyl carbon atoms.

4. The process of claim 1 wherein said alkyl ester is methyl acetate.

5. The process of claim 3 wherein said carboxylic acid is acetic acid and said ether is dimethyl ether.

6. The process of claim 5 further comprising hydrolyzing said recovered ether to form an alcohol.

7. The process of claim 6 wherein said alcohol is methanol.

8. The process of claim 1 wherein said reaction zone is at a pressure of from about 2 psia (13.78 kPa) to about 600 psia (4,137 kPa) and a temperature of from about 30°

C. to about 300°

C.

9. The process of claim 8 wherein said reaction zone is at a pressure of from about 100 psia (689.2 kPa) to about 300 psia (2068 kPa).

10. A process for preparing a carboxylic acid from an alkyl ester having an alkyl group with 1 to 3 carbon atoms comprising:

a. introducing said alkyl ester into a reaction zone of a reactive distillation column wherein said reaction zone is at a temperature and pressure to preferentially hydrolyze said alkyl ester to produce said carboxylic acid and an ether from said ester; and

b. recovering said ether and said carboxylic acid.

11. The process of claim 10 wherein said alkyl ester is methyl acetate.

12. The process of claim 10 wherein said carboxylic acid is acetic acid and said ether is dimethyl ether.

13. The process of claim 10 wherein said reaction zone is at a pressure of from about 100 psia (689.2 kPa) to about 300 psia (2068 kPa) and a temperature of from about 30°

C. to about 300°

C.

14. The process of claim 10 further comprising hydrolyzing said recovered ether to form methanol.

15. The process of claim 11 wherein the molar ratio of water to methyl acetate is from about 0.05 to about 20.

16. The process of claim 15 wherein the molar ratio of water to methyl acetate is from about 0.3 to about 3.

18. The process of claim 17 wherein said reaction zone is at a pressure of from about 100 psia (689.2 kPa) to about 300 psia (2068 kPa) and a temperature of from about 30°

C. to about 300°

C.

19. The process of claim 17 wherein the molar ratio of water to methyl acetate is from about 0.05 to about 20.

20. The process of claim 17 further comprising hydrolyzing said dimethyl ether to produce methanol.

17. A process for preparing acetic acid from methyl acetate comprising:

a. introducing said methyl acetate into a reaction zone of a reactive distillation column wherein said reaction zone is at a temperature and pressure to preferentially hydrolyze said methyl acetate to produce said acetic acid and dimethyl ether from said ester; and

b. recovering said acetic acid and said dimethyl ether.