US3926744A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the recovery of acrylic acid and acrolein
Assignee: Evonik Operations GmbH
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Filing: 1973-12-26
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Granted: 1975-12-16
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Expires: 1993-12-26
Abstract
Abstract There is provided a process for the recovery of acrylic acid and acrolein from the gas mixture resulting from the catalytic gas phase oxidation of propylene or acrolein by washing the gas mixture with liquids in which at first the acrylic acid is dissolved at higher temperature and then the acrolein is dissolved at lower temperature. The improvement comprises washing the gas mixture for the separation of the acrylic acid at temperatures from about 60* to 120* C. with a washing liquid which is a mixture of water and organic liquid and then washing the gas mixture with a washing liquid which is water or a mixture of water and organic liquid at temperatures between 0* and 30* C. The organic liquid used has a higher boiling point than acrylic acid, does form an azeotrope with water alone, but does not form an azeotrope with acrolein or a mixture of water and acrolein, has slight miscibility with water and forms a solution with acrylic acid in which the acrylic acid has an activity coefficient of less than about 1.5.
Inventors
- 👤 Ewald Noll
- 👤 Hans Schaefer
- 👤 Horst Schmid
- 👤 Wolfgang Weigert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:03
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/21; C07C51/25; C07C51/252; C07C45/00; C07C45/78; C07C45/783; C07C51/42; C07C51/43; C07C51/48; Y; Y10; Y10S; Y10S203/00; Y10S203/22
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
58 words
IN A PROCESS FOR THE RECOVERY OF ACRYLIC ACID AND ACROLEIN FROM THE GAS MIXTURE RESULTING FROM THE CATALUTIC GAS PHASE OXIDATIOON OF PROPYLENE OR ACROLEIN BY WASHING THE GAS MIXTURE WITH A LIQUID IN WHICH AT FIRST THE ACRYLIC ACID IS DISSOLVED AT HIGHER TEMPERATURE AND THEN THE ACROLEIN IS DISSOLVED AT LOWER TEMPERATAURE, THE IMPROVEMENT COMPRISING:
Claim 2
Dependent Claim
58 words
IN A PROCESS FOR THE RECOVERY OF ACRYLIC ACID AND ACROLEIN FROM THE GAS MIXTURE RESULTING FROM THE CATALUTIC GAS PHASE OXIDATIOON OF PROPYLENE OR ACROLEIN BY WASHING THE GAS MIXTURE WITH A LIQUID IN WHICH AT FIRST THE ACRYLIC ACID IS DISSOLVED AT HIGHER TEMPERATURE AND THEN THE ACROLEIN IS DISSOLVED AT LOWER TEMPERATAURE, THE IMPROVEMENT COMPRISING:
Claim 3
Dependent Claim
32 words
WASHING THE GAS MIXTURE FOR THE SEPATATION OF THE ACRYLIC ACID AT TEMPERATURES FROM 60* TO 130*C WITH A WASHING LIQUID WHICH IS A MIXTURE OF WATER AND ORGANIC LIQUID; AND THEN
Claim 4
Dependent Claim
32 words
WASHING THE GAS MIXTURE FOR THE SEPATATION OF THE ACRYLIC ACID AT TEMPERATURES FROM 60* TO 130*C WITH A WASHING LIQUID WHICH IS A MIXTURE OF WATER AND ORGANIC LIQUID; AND THEN
Claim 5
Dependent Claim
59 words
WASHING THE GAS MIXTURE WITH A WASHING LIQUID WHICH IS WATER OR A MIXTURE OF WATER ANS ORGANIC LIQUID AT TEMPERATURE BETWEEN 0* AND 30*C., SAID ORGANIC LIQUID IN STEPS (1) AND (2) HAVING A HIGHER BOILING POINT THAN ACRYLIC ACID, FORMING AN AZEOTROPE WITH WATER ALONE, BUT NOT FORMING AS AXEOTROPE WITH ACDROLEIN OR A MIXTURE OF WATER
Claim 6
Dependent Claim
59 words
WASHING THE GAS MIXTURE WITH A WASHING LIQUID WHICH IS WATER OR A MIXTURE OF WATER ANS ORGANIC LIQUID AT TEMPERATURE BETWEEN 0* AND 30*C., SAID ORGANIC LIQUID IN STEPS (1) AND (2) HAVING A HIGHER BOILING POINT THAN ACRYLIC ACID, FORMING AN AZEOTROPE WITH WATER ALONE, BUT NOT FORMING AS AXEOTROPE WITH ACDROLEIN OR A MIXTURE OF WATER
Claim 7
Dependent Claim
88 words
washing the gas mixture with a washing liquid which is water or a mixture of water and organic liquid at temperatures between 0* and 30* C., said organic liquid in steps (1) and (2) having a higher boiling point than acrylic acid, forming an azeotrope with water alone, but not forming as axeotrope with acrolein or a mixture of water and acrolein, having slight miscibility with water and forming a solution with acrylic acid in which the acrylic acid has an activity coefficient of less than about 1.5.
Claim 8
Dependent Claim
88 words
washing the gas mixture with a washing liquid which is water or a mixture of water and organic liquid at temperatures between 0* and 30* C., said organic liquid in steps (1) and (2) having a higher boiling point than acrylic acid, forming an azeotrope with water alone, but not forming as axeotrope with acrolein or a mixture of water and acrolein, having slight miscibility with water and forming a solution with acrylic acid in which the acrylic acid has an activity coefficient of less than about 1.5.
Claim 9
Dependent Claim
30 words
A process according to claim 1 wherein said organic liquid forms a solution with acrylic acid in which the acrylic acid has an activity coefficient of about 1.0 to 0.05.
Claim 10
Dependent Claim
37 words
A process according to claim 1 wherein the organic liquid is monohydric aliphatic alcohol having 4 to 10 carbon atoms, an acetic acid ester of such an alcohol or an acrylic acid ester of such an alcohol.
Claim 11
Dependent Claim
46 words
A process according to claim 3 wherein the organic liquid is an alkanol of 6 to 10 carbon atoms, an alkyl acetate having 5 to 10 carbon atoms in the alkyl group or an alkyl acrylate having 4 to 10 carbon atoms in the alkyl group.
Claim 12
Dependent Claim
26 words
A process according to claim 4 wherein the organic liquid is 2-ethyl hexanol, 2-ethyl hexyl acrylate or a mixture of 2-ethyl hexanol and 2-ethyl hexyl acrylate.
Claim 13
Dependent Claim
62 words
A process according to claim 1 comprising employing the washing liquid first to separate the acrylic acid from the gas mixture, freeing the washing liquid from the acrylic acid, employing the thus freed washing liquid to separate the acrolein, freeing the washing liquid from the acrolein and recycling the finally freed washing liquid to again separate acrylic acid from the gas mixture.
Claim 14
Dependent Claim
94 words
A process according to claim 6 wherein the acrylic acid solution in wash liquid also contains water, acetic acid, formaldehyde and higher boiling carbonyl compounds as impurities, subjecting the solution to distillation to remove water, acetic acid and formaldehyde, adding an amine having at least one hydRogen attached to the amino group to react with the residual carbonyl compounds, distilling to separate the acrylic acid and organic liquid from the amine-carbonyl compound reaction product and then distilling off the acrylic acid from the acrylic acid-organic liquid mixture leaving as a residue the organic liquid.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-15 | 1979-06-16 | 1979-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-15 | 1983-06-16 | 1983-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-15 | 1987-06-16 | 1987-12-16 | $7700.00 | Window Closed / Lapsed |