Patent US3692845A successfully refreshed from Google Patents.
US3692845A
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US
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Purification of phenol
Assignee: Honeywell International Inc
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Filing: 1969-03-12
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Granted: 1972-09-19
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Expires: 1989-03-12
Abstract
Abstract This invention relates to the purification of phenol produced by the decomposition of cumene hydroperoxide by heating the phenol with a polyamine compound to remove carbonyl-bearing impurities and then acidifying the phenol to give a product which remains color stable on aging. After the addition of the polyamine compound, the phenol is distilled free of the polyamine compound and the carbonyl-bearing impurities. This distillation can be carried out either before or after the acid is added.
Inventors
- 👤 Zafarullah K Cheema
- 👤 Pasquale J Apice
- 👤 Edwin D Little
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:12
CPC Classifications
C; C07; C07C; C07C37/00; C07C37/08; C07C39/00; C07C39/02; C07C39/04; C07C407/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
37 words
A process as claimed in claim 1 wherein said phenol is contacted with said polyamine at a temperature of about 60* C. to 200* C. for at least five minutes prior to the addition of said acid.
Claim 2
Dependent Claim
27 words
A process as claimed in claim 2 wherein the amount of polyamine compound used is equal to 0.03 to 1.0 percent of the weight of the phenol.
Claim 3
Dependent Claim
25 words
A process as claimed in claim 2 wherein about 2 to 6 mols of acid or acid anhydride is added per mol of polyamine compound.
Claim 4
Dependent Claim
37 words
A process as claimed in claim 4 wherein after the addition of said acid the reaction mixture is heated at a temperature of 40* to 200* C. for at least one minute prior to said distillation step.
Claim 5
Dependent Claim
39 words
A process as claimed in claim 1 wherein in the polyamine compound of the formula R1, R2 and R3 are all hydrogen, and R is selected from the group consisting of straight chain alkylene, branched chain alkylene, and arylene.
Claim 6
Dependent Claim
27 words
A process as claimed in claim 5 wherein the polyamine compound is hexamethylene diamine and the acid or acid anhydride is phthalic acid or phthalic acid anhydride.
Claim 7
Dependent Claim
37 words
A process as claimed in claim 5 wherein the polyamine compound consists of di-hexamethylene triamine and hIgher homologues thereof of the formula NH2((CH2)6NH)nH wherein n is greater than 2, and the acid anhydride is phthalic acid anhydride.
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) | 1975-09-19 | 1976-03-20 | 1976-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-19 | 1980-03-20 | 1980-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-19 | 1984-03-20 | 1984-09-19 | $7700.00 | Window Closed / Lapsed |