Patent US3617581A successfully refreshed from Google Patents.
US3617581A
Expired / Lapsed
US
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Treatment of water-containing aromatic wastes
Assignee: Dow Chemical Co
•
Filing: 1970-05-01
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Granted: 1971-11-02
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Expires: 1990-05-01
Abstract
Abstract Carbocyclic oxyaromatic and heterocyclic contaminants such as phenols, pyridinols, benzofuran, and derivatives thereof in water are destroyed by dissolving excess alkali in the contaminated water and contacting the alkaline solution with sufficient chlorine to reduce the pH below seven.
Inventors
- 👤 Chun-Shan Wang
- 👤 James P Easterly Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:18
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/72; C02F1/76; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/908; Y10S210/909
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
13 words
The process of claim 1 wherein the alkali metal compound is sodium hydroxide.
Claim 2
Dependent Claim
11 words
The process of claim 1 carried out at about ambient temperature.
Claim 3
Dependent Claim
20 words
The process of claim 1 wherein the solution is contacted with sufficient chlorine to reduce its pH to about 6.
Claim 4
Dependent Claim
20 words
The process of claim 1 wherein the aromatic organic contaminant is an ester or an ether of a chlorinated phenol.
Claim 5
Dependent Claim
14 words
THe process of claim 1 wherein the organic contaminant is a heterocyclic organic compound.
Claim 6
Dependent Claim
19 words
The process of claim 6 wherein the heterocyclic compound is a chlorinated pyridinol or an ester or ether thereof.
Claim 7
Dependent Claim
18 words
The process of claim 5 wherein the organic contaminant is the chlorinated phenyl ester of a phosphorus acid.
Claim 8
Dependent Claim
18 words
The process of claim 7 wherein the organic contaminant is the chlorinated pyridyl ester of a phosphorus acid.
References Cited (Backward Citations)
US2487627A
Cited
GB769283A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-01 | 1975-05-03 | 1975-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-01 | 1979-05-03 | 1979-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-01 | 1983-05-03 | 1983-11-02 | $7700.00 | Window Closed / Lapsed |