Patent US3666992A successfully refreshed from Google Patents.
Patent US3884908A successfully refreshed from Google Patents.
US3884908A
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Strong acid neutralization of polymeric alcohol xanthates
Assignee: Continental Group Inc
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Filing: 1973-03-14
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Granted: 1975-05-20
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Expires: 1993-03-14
Abstract
Abstract A process for neutralizing the free excess alkali in a polymeric alcohol xanthate comprises dispersing particulate polymeric alcohol xanthate in an inert liquid vehicle in which said xanthate is substantially insoluble, adding a substantially stoichiometric quantity of strong acid based on the free alkali content of said xanthate to said dispersion by small increments, and intimately mixing said increments of acid with said particulate xanthate at a rate such that free alkali is neutralized while leaving a xanthate of relatively high D.S.
Inventors
- 👤 N I Burke
- 👤 D J Bridgeford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:02
CPC Classifications
C; C08; C08L; C08L29/00; C08L29/02; C08L29/04; C08B; C08B33/00; C08B9/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
110 words
A PROCESS FOR NEUTRALIZING A SOLID FINELY DIVIDED FILMFORMING ALKALI METAL POLYMERIC ALCOHOL XANTHATE CONTAINING FREE ALKALI BY-PRODUCTS, TO FORM A NEUTRAL STABLE SOLID PRODUCT IN FINELY DIVIDED FORM WHICH COMPRISES: ADDING, IN SMALL INCREMENTS, A SUNSTANTIALLY STOICHIOMETRIC QUANTITY OF STRONG ACID BASED ON THE FREE ALKALI AND ALKALINE BY-PRODUCT CONTENT IN SAID XANTHATE TO A LIQUID SLURRY OF SAID FINELY DIVIDED ALKALI METAL POLYMERIC ALCOHOL XANTHATE CONTAINING FREE ALKALI AND ALKALINE BY-PRODUCTS IN AN INERT LIQUID VEHICLE IN WHICH THE XANTHATE IS SUBSTANTIALLY INSOLUBLE, AND INTIMATELY MIXING SAID ACID AND XANTHATE SLURRY AT A RATE SUFFICIENT TO NEUTRALIZE THE FREE ALKALI AND ALKALINE BYPRODUCTS WITHOUT REGENERATING THE POLYMERIC ALCOHOL.
Claim 2
Dependent Claim
110 words
A PROCESS FOR NEUTRALIZING A SOLID FINELY DIVIDED FILMFORMING ALKALI METAL POLYMERIC ALCOHOL XANTHATE CONTAINING FREE ALKALI BY-PRODUCTS, TO FORM A NEUTRAL STABLE SOLID PRODUCT IN FINELY DIVIDED FORM WHICH COMPRISES: ADDING, IN SMALL INCREMENTS, A SUNSTANTIALLY STOICHIOMETRIC QUANTITY OF STRONG ACID BASED ON THE FREE ALKALI AND ALKALINE BY-PRODUCT CONTENT IN SAID XANTHATE TO A LIQUID SLURRY OF SAID FINELY DIVIDED ALKALI METAL POLYMERIC ALCOHOL XANTHATE CONTAINING FREE ALKALI AND ALKALINE BY-PRODUCTS IN AN INERT LIQUID VEHICLE IN WHICH THE XANTHATE IS SUBSTANTIALLY INSOLUBLE, AND INTIMATELY MIXING SAID ACID AND XANTHATE SLURRY AT A RATE SUFFICIENT TO NEUTRALIZE THE FREE ALKALI AND ALKALINE BYPRODUCTS WITHOUT REGENERATING THE POLYMERIC ALCOHOL.
Claim 3
Dependent Claim
29 words
The process of claim 1 wherein said polymeric alcohol xanthate is cellulose xanthate, amylose xanthate, polyvinyl alcohol xanthate or polyallyl alcohol xanthate, containing free alkali and alkaline thiocarbonate by-products.
Claim 4
Dependent Claim
16 words
The process of claim 1 wherein said strong acid is nitric, hydrochloric, sulfuric, or phosphoric acid.
Claim 5
Dependent Claim
10 words
The process of claim 3 wherein said acid is sulfuric.
Claim 6
Dependent Claim
16 words
The process of claim 1 in which said liquid vehicle is a concentrated aqueous salt solution.
Claim 7
Dependent Claim
23 words
The process of claim 1 in which said liquid vehicle is an organic solvent or mixture of a water-miscible organic solvent with water.
Claim 8
Dependent Claim
29 words
The process of claim 6 in which said liquid vehicle is an aliphatic or aromatic liquid hydrocarbon or mixtures of hydrocarbons, a liquid alcohol, ketone, or substituted acyl amide.
Claim 9
Dependent Claim
31 words
The process of claim 5 in which the neutralization is continued until the product xanthate recovered has a pH of 6 - 10 when redissolved in water at a 1% concentration.
Claim 10
Dependent Claim
31 words
The process of claim 6 in which the neutralization is continued until the product xanthate recovered has a pH of 6 - 10 when redissolved in water at a 1% concentration.
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) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |