US4683065A
Expired / Lapsed
US
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Method for reduction of cod in water
Assignee: Individual
•
Filing: 1985-06-18
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Granted: 1987-07-28
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Expires: 2005-06-18
Abstract
Abstract A method and apparatus for reducing chemical oxygen demand levels in water which includes the steps of: (a) mixing the water to be treated with at least one oxygen source; (b) contacting the water with a first, activated alumina catalyst; (c) contacting the water with a catalyst selected from the group consisting of Group VIIIB metals, Group IB metals or mixtures thereof; (d) reacting chemical contaminants in the water with the oxygen source; and finally (e) contacting the water with an adsorptive material such as activated carbon. The present invention also includes a method and apparatus for regenerating the catalyst in situ by contacting the catalyst with alkaline and acidic aqueous inorganic regeneration solutions.
Inventors
- 👤 Morris Sheikh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 06:16
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/28; C02F1/281; C02F1/72; C02F1/722; C02F1/725; C02F1/283
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
106 words
A method for reducing chemical oxygen demand (COD) levels in water containing chemical contaminants comprising the steps of: (a) adding at least one oxygen source to the water; (b) contacting the water with a first catalyst consisting of activated alumina; (c) contacting the water from (b) with a catalyst selected from the group consisting of Group VIIIB metals, Group IB metals or mixtures thereof; (d) reacting the chemical contaminants entrained in the water with the oxygen source in the presence of the first and second catalysts; and, then (e) contacting the water with an adsorptive material to adsorb any chemical contaminants which remain in the water.
Claim 2
Independent Claim
106 words
A method for reducing chemical oxygen demand (COD) levels in water containing chemical contaminants comprising the steps of: (a) adding at least one oxygen source to the water; (b) contacting the water with a first catalyst consisting of activated alumina; (c) contacting the water from (b) with a catalyst selected from the group consisting of Group VIIIB metals, Group IB metals or mixtures thereof; (d) reacting the chemical contaminants entrained in the water with the oxygen source in the presence of the first and second catalysts; and, then (e) contacting the water with an adsorptive material to adsorb any chemical contaminants which remain in the water.
Claim 3
Dependent Claim
22 words
The method of claim 1 wherein the first and second catalysts and adsorptive material are contained in a plurality of fixed beds.
Claim 4
Dependent Claim
16 words
The method of claim 2 wherein at least one of the fixed beds contains activated alumina.
Claim 5
Dependent Claim
23 words
The method of claim 2 wherein the second catalyst is selected from the group consisting of platinum, palladium, iridium, rhodium or mixtures thereof.
Claim 6
Dependent Claim
12 words
The method of claim 2 wherein the adsorptive material is activated carbon.
Claim 7
Dependent Claim
25 words
The method of claim 1 wherein the oxygen source is selected from the group consisting of air, oxygen enriched air, oxygen, peroxides or mixtures thereof.
Claim 8
Dependent Claim
11 words
The method of claim 6 wherein the oxygen source is gaseous.
Claim 9
Dependent Claim
43 words
The method of claim 1 wherein the oxygen source is present as an oxygen donating compound mixture comprising: (a) a compound selected from the group consisting of air, oxygen, enriched air, oxygen peroxides or mixtures thereof; and (b) an acidic oxygen donor solution.
Claim 10
Dependent Claim
43 words
The method of claim 8 wherein the acidic oxygen donor solution comprises: (a) an inorganic acidic compound capable of dissociating to yield oxygen at a pH between about 2 and about 7; (b) a metal stabilizer; (c) an inorganic acid; and (d) water.
Claim 11
Dependent Claim
51 words
The method of claim 9 wherein the inorganic compound capable of dissociating to yield oxygen is selected from the group consisting of sodium perchlorate, potassium perchlorate, lithium perchlorate, sodium pyrophosphate, lithium pyrophosphate, potassium pyrophosphate, sodium chlorate, potassium chlorate, lithium chlorate, sodium persulfate, potassium persulfate, lithium persulfate, hydrogen peroxide or mixtures thereof.
Claim 12
Dependent Claim
12 words
The method of claim 9 wherein the inorganic acid is sulfuric acid.
Claim 13
Dependent Claim
11 words
The method of claim 9 wherein the metal stabilizer is tin.
Claim 14
Dependent Claim
16 words
The method of claim 8 wherein the oxygendonating compound mixture further comprises: an alkaline donor solution.
Claim 15
Dependent Claim
38 words
The method of claim 13, the alkaline oxygen donor solution comprises: (a) an inorganic alkaline compound capable of dissociating to yield oxygen at a pH between about 7 and about 13; (b) an alkali hydroxide; and (c) water.
Claim 16
Dependent Claim
37 words
The method of claim 14 wherein the inorganic compound capable of dissociating to yield oxygen is selected from the group consisting of sodium perborate, lithium perborate, potassium perborate, sodium permanganate, lithium permanganate, potassium permanganate or mixtures thereof.
Claim 17
Dependent Claim
60 words
The method of claim 1 further comprising: removing organic foulants deposited on the first catalyst and the second catalyst during the catalytic reaction by exposing the first catalyst and the second catalyst to an aqueous, alkaline regeneration solution consisting essentially of: (a) an alkali perborate; (b) an alkali hydroxide; (c) an alkali borate; (d) an alkali silicate; and (e) water.
Claim 18
Dependent Claim
27 words
The alkaline regeneration solution of claim 16 wherein the alkali perborate is selected from the group consisting of sodium perborate, lithium perborate, potassium perborate and mixtures thereof.
Claim 19
Dependent Claim
27 words
The alkaline regeneration solution of claim 16 wherein the alkali hydroxide is selected from the group consisting of sodium hydroxide, potassium hydroxide, lithium hydroxide or mixtures thereof.
Claim 20
Dependent Claim
27 words
The alkaline regeneration solution of claim 16 wherein the alkali borate is selected from the group consisting of sodium borate, lithium borate, potassium borate or mixtures thereof.
Claim 21
Dependent Claim
27 words
The alkaline regeneration solution of claim 16 wherein the alkali silicate is selected from the group consisting of sodium silicate, lithium silicate, potassium silicate or mixtures thereof.
Claim 22
Dependent Claim
72 words
The method of claim 16 wherein the alkaline regeneration solution consists essentially of: (a) from about 1 to about 25 percent by weight potassium hydroxide; (b) from about 2 to about 15 percent by weight sodium perborate; (c) from about 2 to about 15 percent by weight borax; (d) from about 2 to about 15 percent by weight sodium silicate; and (e) from about 30 to about 90 percent by weight water.
Claim 23
Dependent Claim
58 words
The method of claim 16 further comprising: removing inorganic foulants deposited on the catalyst and the second catalyst by exposing the first and second catalysts to an acidic aqueous regeneration solution consisting essentially of an inorganic acid and water, the acidic regeneration solution being applied in sequence after the catalyst has been exposed to the alkaline regeneration solution.
Claim 24
Dependent Claim
35 words
The method of claim 22 wherein the acidic regeneration solution comprises between about 2 percent and about 50 percent by volume hydrochloric acid and between about 50 percent and about 98 percent by volume water.
Claim 25
Dependent Claim
25 words
The method of claim 16 further comprising the step of rinsing the catalyst with clean water after exposing the catalyst to the alkaline regeneration fluid.
Claim 26
Dependent Claim
30 words
The method of claim 22 further comprising the step of rinsing the first catalyst and the second catalyst with clean water after exposing the catalyst to the acidic regeneration fluid.
Claim 27
Dependent Claim
23 words
The method of claim 22 wherein the first catalyst is exposed to the acidic aqueous regeneration solution without similarly exposing the second catalyst.
Claim 28
Dependent Claim
23 words
The method of claim 22 wherein the second catalyst is exposed to the acidic aqueous regeneration solution without similarly exposing the first catalyst.
Claim 29
Dependent Claim
23 words
The method of claim 16 wherein the first catalyst is exposed to the aqueous alkaline regeneration solution without similarly exposing the second catalyst.
Claim 30
Dependent Claim
23 words
The method of claim 16 wherein the second catalyst is exposed to the aqueous, alkaline regeneration solution without similarly exposing the first catalyst.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1990-07-27 | 1991-01-26 | 1991-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-27 | 1995-01-26 | 1995-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-27 | 1999-01-26 | 1999-07-28 | $7700.00 | Window Closed / Lapsed |