US4157300A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the purification of phenol and phenol formaldehyde containing waste water
Assignee: Evonik Operations GmbH
•
Filing: 1977-12-02
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Granted: 1979-06-05
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Expires: 1997-12-02
Abstract
Abstract Phenol or phenol-formaldehyde containing waste water is purified with chlorine dioxide by treating the waste water with alkali or alkaline earth metal chlorite in the presence of formaldehyde and the weight ratio of formaldehyde to phenol is between 0.5 to 2:1 and the mole ratio of the sum of phenol + formaldehyde to chlorite is between 1:1.2 to 1:2, whereupon the treated water is decolorized, in a given case in known manner.
Inventors
- 👤 Helmut Junkermann
- 👤 Volker Hafner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 00:26
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/72; C02F1/76; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/917
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
89 words
In a process for purifying waste water containing phenol with chlorine dioxide, the improvement comprising treating the waste water with alkali or alkaline earth metal chlorite in the presence of formaldehyde, the weight ratio of formaldehyde to phenol being between 0.5 to 2:1 and the molar ratio of the sum of phenol+formaldehyde to chlorite being between 1:1.2 to 1:2 when the chlorite is an alkali metal chlorite and being between 1:0.6 to 1:1 when the chlorite is an alkaline earth metal chlorite whereupon the treated waste water is decolorized.
Claim 2
Dependent Claim
89 words
In a process for purifying waste water containing phenol with chlorine dioxide, the improvement comprising treating the waste water with alkali or alkaline earth metal chlorite in the presence of formaldehyde, the weight ratio of formaldehyde to phenol being between 0.5 to 2:1 and the molar ratio of the sum of phenol+formaldehyde to chlorite being between 1:1.2 to 1:2 when the chlorite is an alkali metal chlorite and being between 1:0.6 to 1:1 when the chlorite is an alkaline earth metal chlorite whereupon the treated waste water is decolorized.
Claim 3
Dependent Claim
16 words
The process of claim 1 wherein the chlorite is sodium chlorite, potassium chlorite or calcium chlorite.
Claim 4
Dependent Claim
11 words
The process of claim 2 wherein the chlorite is sodium chlorite.
Claim 5
Dependent Claim
20 words
The process of claim 1 wherein after treating the waste water with the chlorite it is treated with decolorizing carbon.
Claim 6
Dependent Claim
31 words
The process of claim 4 wherein the chlorite is added at a rate that the chlorine dioxide formed does not exceed the limit of solubility and does not escape as gas.
Claim 7
Dependent Claim
21 words
The process of claim 5 wherein the pH of the waste water is maintained at 4.5 to 9 during the treatment.
Claim 8
Dependent Claim
61 words
The process of claim 6 wherein the pH of the waste water is maintained at 5 to 8 during the treatment, the weight ratio of phenol to formaldehyde is 1:1 and the molar ratio of the sum of phenol+formaldehyde to chlorite is 1:1.5 when the chlorite is sodium chlorite or potassium chlorite and is 1:0.75 when the chlorite is calcium chlorite.
Claim 9
Dependent Claim
11 words
The process of claim 7 wherein the chlorite is sodium chlorite.
Claim 10
Dependent Claim
15 words
The process of claim 4 wherein the weight ratio of phenol to formaldehyde is 1:1.
Claim 11
Dependent Claim
35 words
The process of claim 4 wherein the molar ratio of the sum of phenol+formaldehyde to chlorite is 1:1.5 when the chlorite is sodium or potassium chlorite and is 1:0.75 when the chlorite is calcium chlorite.
Claim 12
Dependent Claim
85 words
The process of claim 1 wherein the improvement consists essentially of treating the waste water with alkali or alkaline earth metal chlorite in the presence of formaldehyde, the weight ratio of formaldehyde to phenol being between 0.5 to 2:1 and the molar ratio of the sum of phenol+formaldehyde to chlorite being between 1:1.2 to 1:2 when the chlorite is an alkali metal chlorite and being between 1:0.6 to 1:1 when the chlorite is an alkaline earth metal chlorite whereupon the treated waste water is decolorized.
Claim 13
Dependent Claim
84 words
The process of claim 1 wherein the improvement consists of treating the waste water with alkali or alkaline earth metal chlorite in the presence of formaldehyde, the weight ratio of formaldehyde to phenol being between 0.5 to 2:1 and the molar ratio of the sum of phenol+formaldehyde to chlorite being between 1:1.2 to 1:2 when the chlorite is an alkali metal chlorite and being between 1:0.6 to 1:1 when the chlorite is an alkaline earth metal chlorite whereupon the treated waste water is decolorized.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-06-04 | 1982-12-04 | 1983-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-06-04 | 1986-12-04 | 1987-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-06-04 | 1990-12-04 | 1991-06-05 | $7700.00 | Window Closed / Lapsed |