US3972950A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the purification of bisphenol A
Assignee: Shell USA Inc
•
Filing: 1975-05-07
•
Granted: 1976-08-03
•
Expires: 1995-05-07
Abstract
Abstract Crude 2,2-bis(4-hydroxyphenyl)propane containing impurities such as 2-(2-hydroxyphenyl)-2-(4-hydroxyphenyl)propane is purified by first dissolving the crude material in a polyhydroxy solvent then adding water and an ether having a boiling point less than 110°C whereby the ether extracts the 2,2-bis(4-hydroxyphenyl)propane. The ether-2,2-bis(4-hydroxyphenyl)propane extract is then distilled in the presence of toluene wherein the toluene-2,2-bis(4-hydroxyphenyl)propane bottoms product is separated and cooled to form a purified 2,2-bis(4-hydroxyphenyl)propane precipitate which is subsequently recovered.
Inventors
- 👤 Arien Kwantes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:16
CPC Classifications
C; C07; C07C; C07C37/00; C07C37/68; C07C37/685; C07C37/70; C07C37/72; C07C37/74
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
129 words
A process for the purification of a crude 2,2-bis(4-hydroxyphenyl)propane mixture prepared by condensing phenol with acetone or 2,2-dimethyl-1,3-dioxolane, said mixture being substantially free of phenol, which process comprises: a. dissolving the crude 2,2-bis(4-hydroxyphenyl)propane and impurities in a polyhydroxy solvent selected from alkane diols and alkane triols; b. contacting the polyhydroxy solvent-crude 2,2-bis(4-hydroxyphenyl)propane solution with water and an ether selected from the group consisting of diethyl ether, ethyl-n-propyl ether, ethylisopropyl ether, methyl-tert-butyl ether, di-n-propyl ether, diisopropyl ether and furan, wherein said ether extracts the 2,2-bis(4-hydroxyphenyl)propane; c. separating the ether-2,2-bis(4-hydroxyphenyl)propane extract; d. distilling the ether-2,2-bis(4-hydroxyphenyl)propane extract in a column and in the presence of toluene and recovering as bottoms product a toluene-2,2-bis(4-hydroxyphenyl)propane solution; e. cooling the toluene-2,2-bis(4-hydroxyphenyl)propane bottoms product to form a purified 2,2-bis(4-hydroxyphenyl)propane precipitate; and f. recovering the purified 2,2-bis(4-hydroxyphenyl)propane.
Claim 2
Dependent Claim
129 words
A process for the purification of a crude 2,2-bis(4-hydroxyphenyl)propane mixture prepared by condensing phenol with acetone or 2,2-dimethyl-1,3-dioxolane, said mixture being substantially free of phenol, which process comprises: a. dissolving the crude 2,2-bis(4-hydroxyphenyl)propane and impurities in a polyhydroxy solvent selected from alkane diols and alkane triols; b. contacting the polyhydroxy solvent-crude 2,2-bis(4-hydroxyphenyl)propane solution with water and an ether selected from the group consisting of diethyl ether, ethyl-n-propyl ether, ethylisopropyl ether, methyl-tert-butyl ether, di-n-propyl ether, diisopropyl ether and furan, wherein said ether extracts the 2,2-bis(4-hydroxyphenyl)propane; c. separating the ether-2,2-bis(4-hydroxyphenyl)propane extract; d. distilling the ether-2,2-bis(4-hydroxyphenyl)propane extract in a column and in the presence of toluene and recovering as bottoms product a toluene-2,2-bis(4-hydroxyphenyl)propane solution; e. cooling the toluene-2,2-bis(4-hydroxyphenyl)propane bottoms product to form a purified 2,2-bis(4-hydroxyphenyl)propane precipitate; and f. recovering the purified 2,2-bis(4-hydroxyphenyl)propane.
Claim 3
Dependent Claim
79 words
The process according to claim 1 wherein the weight ratio of polyhydroxy solvent to crude 2,2-bis(4-hydroxyphenyl)propane in step 1(a) is between about 80:20 and about 75:25; the weight ratio of ether to 2,2-bis(4-hydroxyphenyl)propane in step 1(b) is between about 1:5 and about 10:1; the weight ratio of water to polyhydroxy solvent in step 1(b) is between about 40:60 and about 90:10; and the weight ratio of toluene to 2,2-bis(4-hydroxyphenyl)propane in step 1(d) is between about 3:2 and about 5:2.
Claim 4
Dependent Claim
19 words
The process according to claim 2 wherein the polyhydroxy solvent is ethylene glycol and the ether is diisopropyl ether.
Claim 5
Dependent Claim
31 words
The process according to claim 3 wherein the polyhydroxy solvent-crude 2,2-bis(4-hydroxyphenyl)propane solution is contacted with water and an ether at a temperature of between about 30° C and about 50° C.
Claim 6
Dependent Claim
54 words
The process according to claim 4 wherein the toluene-2,2-bis(4-hydroxyphenyl)propane solution obtained as a bottoms product in step 1(d) has a temperature of between about 100° and about 130° C and wherein said toluene-2,2-bis(4-hydroxyphenyl)propane solution is cooled to a temperature of between about 40° C and about 80° C to form a purified 2,2-bis(4-hydroxyphenyl)propane precipitate.
References Cited (Backward Citations)
US2959622A
Cited
US3535389A
Cited
US3207795A
Cited
US3290391A
Cited
US3326986A
Cited
US3493622A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-03 | 1980-02-02 | 1980-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-03 | 1984-02-02 | 1984-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-03 | 1988-02-02 | 1988-08-03 | $7700.00 | Window Closed / Lapsed |