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US3692845A Expired / Lapsed US ⏱️ 0.0 years remaining

Purification of phenol

Assignee: Honeywell International Inc
•
Filing: 1969-03-12
•
Granted: 1972-09-19
•
Expires: 1989-03-12
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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 04:45
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)

US1942838A Cited
US2490670A Cited
US3285973A Cited

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

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