US3859175A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for purifying acrylic acid by plural stage distillation and an extraction
Assignee: Sumitomo Chemical Co Ltd
•
Filing: 1973-05-21
•
Granted: 1975-01-07
•
Expires: 1993-05-21
Abstract
Abstract Acrylic acid is purified from an aequeous solution containing acrylic acid and acetic acid, by distilling azeotropically with a dual solvent consisting of the first component capable of forming an azeotropic mixture with acrylic acid, acetic acid and water and the second component having a lower boiling point than that of acetic acid in a distillation column under a pressure of 300 mmHg absolute or less to distill off substantially all of acetic acid, water and the second component together with some portions of the first component at the head of the column and then distilling the resulting bottoms containing acrylic acid and the first component, almost free from acetic acid, in another distillation column under a pressure of 300 mmHg absolute or less, using water as an entrainer for the first component, where acrylic acid is obtained at a high concentration in water from the bottom.
Inventors
- 👤 Tetsuya Ohrui
- 👤 Yasuhito Sakakibara
- 👤 Yukinaga Aono
- 👤 Michio Kato
- 👤 Hiroshi Takao
- 👤 Masami Ayano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:37
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/43; C07C51/44; C07C51/46; C07C51/48; Y; Y10; Y10S; Y10S203/00; Y10S203/22
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
137 words
FEEDING A MIXTURE COMPRISING ACRYLIC ACID, ACETIC ACID, WATER AND A DUAL SOLVENT CONSISTING OF AN ORGANIC SOLVENT WHICH FORMS AN AZEOTROPIC MISTURE WITH ACRYLIC ACID, ACETIC ACID AND WATER (THE FIRST COMPONENT) AND ANOTHER ORGANIC SOLVENT HAVING A BOILING POINT LOWER THAN THAT OF ACETIC ACID (THE SECOND COMPONENT) TO THE TOP OF A FIRST DISTILLATION COLUMN OPERATED UNDER A PRESSURE OF 300 MMHG ABSOLUTE OR LESS, THEREBY DISTILLING THE MIXTURE, OBTAINING ACRYLIC ACID AT A HIGH CONCENTRATION AND A PORTION OF THE FEED OF THE FIRST COMPONENT, ALMOST FREE FROM ACETIC ACID FROM THE BOTTOM AND DISTILLING OFF ALL OF THE SECOND COMPONENT, A PORTION OF THE FIRST COMPONENT, ALL OF WATER AND 10 PERCENT BY WEIGHT OR MORE OF THE FEED OF ACRYLIC ACID TOGETHER WITH ACETIC ACID FROM THE TOP AS A DISTILLATE;
Claim 2
Dependent Claim
137 words
FEEDING A MIXTURE COMPRISING ACRYLIC ACID, ACETIC ACID, WATER AND A DUAL SOLVENT CONSISTING OF AN ORGANIC SOLVENT WHICH FORMS AN AZEOTROPIC MISTURE WITH ACRYLIC ACID, ACETIC ACID AND WATER (THE FIRST COMPONENT) AND ANOTHER ORGANIC SOLVENT HAVING A BOILING POINT LOWER THAN THAT OF ACETIC ACID (THE SECOND COMPONENT) TO THE TOP OF A FIRST DISTILLATION COLUMN OPERATED UNDER A PRESSURE OF 300 MMHG ABSOLUTE OR LESS, THEREBY DISTILLING THE MIXTURE, OBTAINING ACRYLIC ACID AT A HIGH CONCENTRATION AND A PORTION OF THE FEED OF THE FIRST COMPONENT, ALMOST FREE FROM ACETIC ACID FROM THE BOTTOM AND DISTILLING OFF ALL OF THE SECOND COMPONENT, A PORTION OF THE FIRST COMPONENT, ALL OF WATER AND 10 PERCENT BY WEIGHT OR MORE OF THE FEED OF ACRYLIC ACID TOGETHER WITH ACETIC ACID FROM THE TOP AS A DISTILLATE;
Claim 3
Dependent Claim
8 words
A PROCESS FOR SEPARATING ACRYLIC ACID, WHICH COMPRISES:
Claim 4
Dependent Claim
8 words
A PROCESS FOR SEPARATING ACRYLIC ACID, WHICH COMPRISES:
Claim 5
Dependent Claim
46 words
FEEDING THE DISTILLATE TO MIDDLE STAGE OF A SECOND DISTILLATION COLUMN, THEREBY DISTILLING THE DISTILLATE, OBTAINING THE SECOND COMPONENT AND WATER FROM THE TOP AS A DISTILLATE, AND OBTAINING A SOLUTION OF CONCENTRATED ACETIC ACID, ACRYLIC ACID AND THE FIRST COMPONENT FROM THE BOTTOM OR BOTTOMS;
Claim 6
Dependent Claim
46 words
FEEDING THE DISTILLATE TO MIDDLE STAGE OF A SECOND DISTILLATION COLUMN, THEREBY DISTILLING THE DISTILLATE, OBTAINING THE SECOND COMPONENT AND WATER FROM THE TOP AS A DISTILLATE, AND OBTAINING A SOLUTION OF CONCENTRATED ACETIC ACID, ACRYLIC ACID AND THE FIRST COMPONENT FROM THE BOTTOM OR BOTTOMS;
Claim 7
Dependent Claim
17 words
A process according to claim 1, wherein the first component is ethylbenzene, o-xylene, m-xylene, p-xylene or octane.
Claim 8
Dependent Claim
47 words
feeding the distillate to a middle stage of a second distillation column, thereby distilling the distillate, obtaining the second component and water from the top as a distillate, and obtaining a solution of concentrated acetic acid, acrylic acid and the first component from the bottom or bottoms;
Claim 9
Dependent Claim
47 words
feeding the distillate to a middle stage of a second distillation column, thereby distilling the distillate, obtaining the second component and water from the top as a distillate, and obtaining a solution of concentrated acetic acid, acrylic acid and the first component from the bottom or bottoms;
Claim 10
Dependent Claim
55 words
feeding the resulting bottoms to a middle stage of a third distilling column, thereby distilling the bottoms under a pressure of 300 mmHg absolute or less, obtaining a mixture containing acetic acid and the first component from the top, and obtaining a solution of acrylic acid and the first component from the bottom as bottoms;
Claim 11
Dependent Claim
55 words
feeding the resulting bottoms to a middle stage of a third distilling column, thereby distilling the bottoms under a pressure of 300 mmHg absolute or less, obtaining a mixture containing acetic acid and the first component from the top, and obtaining a solution of acrylic acid and the first component from the bottom as bottoms;
Claim 12
Dependent Claim
17 words
A process according to claim 1, wherein the second component is methylethylketone, methyl acetate or ethyl acetate.
Claim 13
Dependent Claim
29 words
FEEDING THE RESULTING BOTTOMS TO A MIDDLE STAGE OF A THIRD DISTILLING COLUMN, THEREBY DISTILLING THE BOTTOMS UNDER A PRESSURE OF 300 MMHG ABSOLUTE OR LESS, OBTAINING A MIX-
Claim 14
Dependent Claim
29 words
FEEDING THE RESULTING BOTTOMS TO A MIDDLE STAGE OF A THIRD DISTILLING COLUMN, THEREBY DISTILLING THE BOTTOMS UNDER A PRESSURE OF 300 MMHG ABSOLUTE OR LESS, OBTAINING A MIX-
Claim 15
Dependent Claim
14 words
FEEDING A SOLUTION OF ACRYLIC ACID IN THE FIRST COMPONENT THE FIRST DISTILLATION COLUMN;
Claim 16
Dependent Claim
14 words
FEEDING A SOLUTION OF ACRYLIC ACID IN THE FIRST COMPONENT THE FIRST DISTILLATION COLUMN;
Claim 17
Dependent Claim
31 words
A process according to claim 1 wherein the bottoms of the third distillation column is joined with the bottoms of the first distillation column to feed to the fourth distillation column.
Claim 18
Dependent Claim
13 words
feeding the bottoms from the third distillation column to the first distillation column;
Claim 19
Dependent Claim
13 words
feeding the bottoms from the third distillation column to the first distillation column;
Claim 20
Dependent Claim
83 words
FEEDING A SOLUTION OF ACRYLIC ACID IN THE FIRST COMPONENT OBTAINED FROM THE BOTTOM OF THE FIRST DISTILLATION COLUMN TO THE TOP OF A FOURTH DISTILLATION COLUMN, THEREBY DISTILLING THE BOTTOMS UNDER A PRESSURE OF 300 MMHG ABLOLUTE OR LESS, WITH WATER AS AN ENTRAINER FOR THE FIRST COMPONENT, OBTAINING AN AZEOTROPIC MIXTURE OF WATER AND THE FIRST COMPONENT TOGETHER WITH ACRYLIC ACID FROM THE TOP AS A DISTILLATE, AND OBTAINING ACRYLIC ACID AT A HIGH CONCENTRATION FROM THE BOTTOM AS A PRODUCT;
Claim 21
Dependent Claim
83 words
FEEDING A SOLUTION OF ACRYLIC ACID IN THE FIRST COMPONENT OBTAINED FROM THE BOTTOM OF THE FIRST DISTILLATION COLUMN TO THE TOP OF A FOURTH DISTILLATION COLUMN, THEREBY DISTILLING THE BOTTOMS UNDER A PRESSURE OF 300 MMHG ABLOLUTE OR LESS, WITH WATER AS AN ENTRAINER FOR THE FIRST COMPONENT, OBTAINING AN AZEOTROPIC MIXTURE OF WATER AND THE FIRST COMPONENT TOGETHER WITH ACRYLIC ACID FROM THE TOP AS A DISTILLATE, AND OBTAINING ACRYLIC ACID AT A HIGH CONCENTRATION FROM THE BOTTOM AS A PRODUCT;
Claim 22
Dependent Claim
83 words
feeding a solution of acrylic acid in the first component obtained from the bottom of the first distillation column to the top of a fourth distillation column, thereby distilling the bottoms under a pressure of 300 mmHg absolute or less, with water as an entrainer for the first component, obtaining an azeotropic mixture of water and the first component together with acrylic acid from the top as a distillate, and obtaining acrylic acid at a high concentration from the bottom as a product;
Claim 23
Dependent Claim
83 words
feeding a solution of acrylic acid in the first component obtained from the bottom of the first distillation column to the top of a fourth distillation column, thereby distilling the bottoms under a pressure of 300 mmHg absolute or less, with water as an entrainer for the first component, obtaining an azeotropic mixture of water and the first component together with acrylic acid from the top as a distillate, and obtaining acrylic acid at a high concentration from the bottom as a product;
Claim 24
Dependent Claim
18 words
separating the distillate of the fourth distillation column into an oil layer and an aqueous layer by decantation;
Claim 25
Dependent Claim
18 words
separating the distillate of the fourth distillation column into an oil layer and an aqueous layer by decantation;
Claim 26
Dependent Claim
18 words
SEPARATING THE DISTILLATE OF THE FOURTH DISTILLATION COLUMN INTO AN OIL LAYER AND AN AQUEOUS LAYER BY DECANTATION;
Claim 27
Dependent Claim
18 words
SEPARATING THE DISTILLATE OF THE FOURTH DISTILLATION COLUMN INTO AN OIL LAYER AND AN AQUEOUS LAYER BY DECANTATION;
Claim 28
Dependent Claim
36 words
FEEDING THE OIL LAYER CONTAINING THE FIRST COMPONENT AND ACRYLIC ACID TO THE BOTTOM OF AN EXTRACTION COLUMN, THEREBY EXTRACTING ACRYLIC ACID WITH WATER AS AN EXTRACTING AGENT AND RECOVERING THE FIRST COMPONENT AS A RAFFINATE;
Claim 29
Dependent Claim
36 words
FEEDING THE OIL LAYER CONTAINING THE FIRST COMPONENT AND ACRYLIC ACID TO THE BOTTOM OF AN EXTRACTION COLUMN, THEREBY EXTRACTING ACRYLIC ACID WITH WATER AS AN EXTRACTING AGENT AND RECOVERING THE FIRST COMPONENT AS A RAFFINATE;
Claim 30
Dependent Claim
36 words
feeding the oil layer containing the first component and acrylic acid to the bottom of an extraction column, thereby extracting acrylic acid with water as an extracting agent and recovering the first component as a raffinate;
Claim 31
Dependent Claim
36 words
feeding the oil layer containing the first component and acrylic acid to the bottom of an extraction column, thereby extracting acrylic acid with water as an extracting agent and recovering the first component as a raffinate;
Claim 32
Dependent Claim
28 words
refluxing the resulting aqueous acrylic acid extract after being joined with the aqueous layer separated by the decantation back to the top of the fourth distillation column, and
Claim 33
Dependent Claim
28 words
refluxing the resulting aqueous acrylic acid extract after being joined with the aqueous layer separated by the decantation back to the top of the fourth distillation column, and
Claim 34
Dependent Claim
28 words
REFLUXING THE RESULTING AQUEOUS ACRYLIC ACID EXTRACT AFTER BEING JOINED WITH THE AQUEOUS LAYER SEPARATED BY THE DECANTATION BACK TO THE TOP OF THE FOURTH DISTILLATION COLUMN, AND
Claim 35
Dependent Claim
28 words
REFLUXING THE RESULTING AQUEOUS ACRYLIC ACID EXTRACT AFTER BEING JOINED WITH THE AQUEOUS LAYER SEPARATED BY THE DECANTATION BACK TO THE TOP OF THE FOURTH DISTILLATION COLUMN, AND
Claim 36
Dependent Claim
3 words
RECOVERING ACRYLIC ACID.
Claim 37
Dependent Claim
3 words
RECOVERING ACRYLIC ACID.
Claim 38
Dependent Claim
3 words
recovering acrylic acid.
Claim 39
Dependent Claim
3 words
recovering acrylic acid.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-06 | 1978-07-08 | 1979-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-06 | 1982-07-08 | 1983-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-06 | 1986-07-08 | 1987-01-07 | $7700.00 | Window Closed / Lapsed |