Patent US3914290A successfully refreshed from Google Patents.
US3914290A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for esterifying acrylic acid
Assignee: Rohm and Haas Co
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Filing: 1969-05-07
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Granted: 1975-10-21
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Expires: 1989-05-07
Abstract
Abstract A continuous process for producing an acrylate which comprises reacting acrylic acid with methanol or ethanol using the reactive-distillation method wherein acrylic acid is fed into the upper section of a distillation column and an alcohol is fed into the lower section. The reactive-distillation is carried out by maintaining a reflux ratio at 1 or less thereby distilling out the ester produced with almost all of the water added and produced through the reaction of esterification from the top of the column and high boiling point materials by-produced are discharged from the bottom of said column in a state substantially free from unreacted acrylic acid.
Inventors
- 👤 Susumu Otsuki
- 👤 Isao Miyanohara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:06
CPC Classifications
C; C07; C07C; C07C69/00; C07C69/52; C07C69/533; C07C69/54; C07C67/00; C07C67/08; Y; Y02; Y02P; Y02P20/00; Y02P20/10; Y02P20/50; Y02P20/582; Y10; Y10S; Y10S203/00; Y10S203/06; Y10S203/22
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
145 words
IN A PROCESS FOR PRODUCING AN ESTER FROM ACRYLIC ACID AND AN ALIPHATIC ALCOHOL IN THE PRESENCE OF A CATALYST COMPRISING SULFURIC ACID IN A DISTILLATION COLUMN SERVING AS A REACTOR, WHEREIN ACRYLIC ACID IS FED TO A FEED TRAY THEREIN IN AN UPPER SECTION OF SAID COLUMN AND METHYL OR ETHYL ALCOHOL IS FED INTO A LOWER SECTION OF SAID COLUMN, SAID CATALYST IS FED INTO AN UPPER SECTION OF SAID COLUMN, WHEREIN CONTINUOUS REACTION AND DISTILLATION ARE PREFORMED SIMULTANEOUSLY IN SAID COLUMN, AND WHEREIN SAID ESTER IS DISTILLED FROM SAID COLUMN, THE IMPROVEMENT WHICH COMPRISES MAINTAINING A CONCENTRATION OF AT LEAST 20 PERCENT OF ACRYLIC ACID IN THE CONBINED WEIGHTS OF THE ACRYLIC ACID AND SULFURIC ACID SO FED, SO FEEDING ACRYLIC ACID HAVING A CONCENTRATION OF MORE THAN 60 PERCENT, AND MAINTAINING A REFLUX RATIO OF UP TO 1 IN SAID COLUMN.
Claim 2
Dependent Claim
145 words
IN A PROCESS FOR PRODUCING AN ESTER FROM ACRYLIC ACID AND AN ALIPHATIC ALCOHOL IN THE PRESENCE OF A CATALYST COMPRISING SULFURIC ACID IN A DISTILLATION COLUMN SERVING AS A REACTOR, WHEREIN ACRYLIC ACID IS FED TO A FEED TRAY THEREIN IN AN UPPER SECTION OF SAID COLUMN AND METHYL OR ETHYL ALCOHOL IS FED INTO A LOWER SECTION OF SAID COLUMN, SAID CATALYST IS FED INTO AN UPPER SECTION OF SAID COLUMN, WHEREIN CONTINUOUS REACTION AND DISTILLATION ARE PREFORMED SIMULTANEOUSLY IN SAID COLUMN, AND WHEREIN SAID ESTER IS DISTILLED FROM SAID COLUMN, THE IMPROVEMENT WHICH COMPRISES MAINTAINING A CONCENTRATION OF AT LEAST 20 PERCENT OF ACRYLIC ACID IN THE CONBINED WEIGHTS OF THE ACRYLIC ACID AND SULFURIC ACID SO FED, SO FEEDING ACRYLIC ACID HAVING A CONCENTRATION OF MORE THAN 60 PERCENT, AND MAINTAINING A REFLUX RATIO OF UP TO 1 IN SAID COLUMN.
Claim 3
Dependent Claim
28 words
The process of claim 1, wherein an upper part of said column is maintained at a higher temperature than the temperature at a lower part of said column.
Claim 4
Dependent Claim
18 words
The process of claim 1 wherein 3-6 moles of alcohol are charged per one mole of acrylic acid.
Claim 5
Dependent Claim
27 words
The process of claim 1, wherein the concentration of sulfuric acid in the sulfuric acid feed tray is kept within a range of from 2-5% by weight.
Claim 6
Dependent Claim
18 words
The process of claim 1, wherein a polymerization inhibitor is added to the column from the top thereof.
Claim 7
Dependent Claim
11 words
The process of claim 1, wherein the alcohol is methyl alcohol.
Claim 8
Dependent Claim
11 words
The process of claim 1, wherein the alcohol is ethyl alcohol.
Claim 9
Dependent Claim
13 words
The process of claim 1, wherein the reflux ratio is less than 0.5.
References Cited (Backward Citations)
BE627490A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-20 | 1979-04-21 | 1979-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-20 | 1983-04-21 | 1983-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-20 | 1987-04-21 | 1987-10-21 | $7700.00 | Window Closed / Lapsed |