US3933630A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of waste water containing phthalic esters
Assignee: Rhone Progil SA
•
Filing: 1974-09-03
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Granted: 1976-01-20
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Expires: 1994-09-03
Abstract
Abstract A process for the treatment of waste waters from the preparation of phthalic esters of alcohols to reduce the BOD and recover alcohols comprising treating the waste water with a strong acid and then extracting the acidified waste water with an alcohol, preferably the same as the alcohol used to form the phthalic ester.
Inventors
- 👤 Jacques Helgorsky
- 👤 Michel Auroy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 05:38
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/26
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
76 words
A process for the purification of waste water resulting from the production of phthalic esters by esterification of phthalic acid or anhydride with alcohols having more than 4 carbon atoms, which comprises acidifying the waste water with a strong acid to attain a free acidity of the waste water greater than 0.05 N and extracting the acidified water with an alcohol having more than 4 carbon atoms for removal of organic impurities from the acidified water.
Claim 2
Dependent Claim
76 words
A process for the purification of waste water resulting from the production of phthalic esters by esterification of phthalic acid or anhydride with alcohols having more than 4 carbon atoms, which comprises acidifying the waste water with a strong acid to attain a free acidity of the waste water greater than 0.05 N and extracting the acidified water with an alcohol having more than 4 carbon atoms for removal of organic impurities from the acidified water.
Claim 3
Dependent Claim
13 words
A process according to claim 1, wherein the strong acid is sulfuric acid.
Claim 4
Dependent Claim
24 words
A process according to claim 1, wherein the alcohol used for the extraction is the same as that used to form the phthalic ester.
Claim 5
Dependent Claim
30 words
A process according to claim 1, wherein the waste water is from the acid-catalyzed esterification of a phthalic anhydride or acid with an alcohol having more than 4 carbon atoms.
Claim 6
Dependent Claim
25 words
A process according to claim 4, wherein all the alcohol necessary for the esterification step is derived from the alcohol used in the extraction step.
Claim 7
Dependent Claim
27 words
A process according to claim 4, wherein only part of the alcohol necessary for the esterification step is derived from the alcohol used in the extraction step.
Claim 8
Dependent Claim
25 words
A process according to claim 1, wherein the free acidity of the waste water after acidification is within the range of 0.05 to 0.5 N.
Claim 9
Dependent Claim
44 words
A process according to claim 4, wherein the waste water is from the industrial production of dioctyl (di-2-ethylhexyl) phthalate, the free acidity of the acidified waste water is from 0.15 to 0.5 N and the alcohol used for the extraction is octyl alcohol (2-ethylhexanol).
Claim 10
Dependent Claim
41 words
A process according to claim 4, wherein the waste water is from the industrial production of diisononyl phthalate, the free acidity of the acidified waste water is from 0.05 to 0.20 N and the alcohol used for the extraction is isononanol.
Claim 11
Dependent Claim
29 words
A process according to claim 1, which includes the step of separating the alcohol extract from a remaining organic phase and neutralizing the aqueous phase from the extraction step.
Claim 12
Dependent Claim
26 words
A process according to claim 10, which includes the step of distilling the neutralized aqueous phase to remove at least a portion of any residual alcohol.
References Cited (Backward Citations)
US2644009A
Cited
US3476796A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-01-19 | 1979-07-21 | 1980-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-19 | 1983-07-21 | 1984-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-19 | 1987-07-21 | 1988-01-20 | $7700.00 | Window Closed / Lapsed |