Patent US6338635B1 successfully refreshed from Google Patents.
US3700728A
Expired / Lapsed
US
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Solubilization of humic acids, lignites and coals
Assignee: Canadian Patents and Development Ltd
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Filing: 1968-12-30
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Granted: 1972-10-24
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Expires: 1988-12-30
Abstract
Abstract A process for the preparation of water-soluble products from humic acids, lignites and pre-oxidized coals which are reacted with a sulfonating agent to form a sulfite or a bisulfite in situ, in an alkaline medium. The water-soluble product is useable as a well-drilling fluid.
Inventors
- 👤 Speros E Moschopedis
- 👤 Ernst Czakert
- 👤 Stephen M Creighton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:09
CPC Classifications
C; C08; C08H; C08H99/00; C09; C09K; C09K8/00; C09K8/02; C09K8/04; C09K8/14; C09K8/18; C09K8/20; C09K8/203
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
21 words
The process of claim 1 wherein up to about 25 percent by weight of chlorine is incorporated into said water-soluble product.
Claim 2
Dependent Claim
21 words
The process of claim 1 wherein up to about 25 percent by weight of bromine is incorporated into said water-soluble product.
Claim 3
Dependent Claim
22 words
The process of claim 1 wherein the chlorination is effected by bubbling gaseous chlorine through an aqueous solution of said water-soluble product.
Claim 4
Dependent Claim
9 words
A chlorinated or brominated water-soluble sulfonated humic acid product.
Claim 5
Dependent Claim
13 words
The product of claim 5 containing up to 25 percent by weight chlorine.
Claim 6
Dependent Claim
13 words
The product of claim 5 containing up to 25 percent by weight bromine.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |