Patent US3922294A successfully refreshed from Google Patents.
US3922294A
Expired / Lapsed
US
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Process for the manufacture of isopropyl esters by the reaction of propylene with carboxylic acids
Assignee: Hoechst AG
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Filing: 1974-02-07
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Granted: 1975-11-25
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Expires: 1994-02-07
Abstract
Abstract Isopropyl esters of carboxylic acids having up to 20 carbon atoms are prepared by passing propylene and the respective carboxylic acid continuously in parallel flow over an acid ion exchanger of the sulfonic acid type. The service life of the catalyst is greatly improved by adding a small amount of a strong mineral acid.
Inventors
- 👤 Ernst Ingo Leupold
- 👤 Hans-Jurgen Arpe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:00
CPC Classifications
C; C07; C07C; C07C67/00; C07C67/04; C07C67/48; C07C67/56
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
78 words
A PROCESS FOR THE MANUFACTURE OF ISOPROPYL ESTERS BY REACTING PROPYLENE WITH CARBOXYLIC ACIDS, IN TRICKLING PHASE, WHICH COMPRISES THE STEP OF PASSING GASEOUS PROPYLENE AND AN ALIPHATIC, CYCLALIPHATIC, OR AROMATIC CARBOXYLIC ACID HAVING UP TO 20 CARBON ATOMS EITHER IN LIQUID FORM OR IN THE FORM OF A SOLUTION IN AN INERT SOLVENT CONTINUOUSLY IN PARALLEL FLOW OVER AN ACID ION EXCHANGER OF THESULFONIC ACID TYPE AT A TEMPERATURE IN THE RANGE OF FROM 40* TO 170*C.
Claim 2
Dependent Claim
78 words
A PROCESS FOR THE MANUFACTURE OF ISOPROPYL ESTERS BY REACTING PROPYLENE WITH CARBOXYLIC ACIDS, IN TRICKLING PHASE, WHICH COMPRISES THE STEP OF PASSING GASEOUS PROPYLENE AND AN ALIPHATIC, CYCLALIPHATIC, OR AROMATIC CARBOXYLIC ACID HAVING UP TO 20 CARBON ATOMS EITHER IN LIQUID FORM OR IN THE FORM OF A SOLUTION IN AN INERT SOLVENT CONTINUOUSLY IN PARALLEL FLOW OVER AN ACID ION EXCHANGER OF THESULFONIC ACID TYPE AT A TEMPERATURE IN THE RANGE OF FROM 40* TO 170*C.
Claim 3
Dependent Claim
18 words
The process of claim 1, wherein a solution of the carboxylic aciD in its isopropyl ester is reacted.
Claim 4
Dependent Claim
27 words
The process of claim 1, wherein the isopropyl ester is continuously distilled off from the liquid reaction mixture and the remaining mixture is recycled into the reaction.
Claim 5
Dependent Claim
54 words
The process of claim 1, wherein the reaction is carried out in the presence of 0.05 to 3% by weight, calculated on the weight of the carboxylic acid, of a strong acid having a Pk value of less than 4, and wherein said strong acid is H2SO4, H3PO4, HCl, HClO4 or p-toluene sulfonic acid.
Claim 6
Dependent Claim
14 words
The process of claim 4, wherein sulfuric acid is added to the carboxylic acid.
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) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |