US3844912A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for treating electrolytic manganese dioxide
Assignee: Mitsui Kinzoku Co Ltd
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Filing: 1973-07-05
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Granted: 1974-10-29
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Expires: 1993-07-05
Abstract
Abstract Manganese dioxide electrolytically deposited by the electrolysis of an aqueous sulfuric acid solution of manganese sulfate in an electrolyzer having a member of lead is subjected to mutual abrasion and treated with water and/or neutralizing agent, whereby lead and sulfuric ion-containing compounds occluded in the manganese dioxide are reduced sufficiently to be used as a depolarlizer of a dry cell which has a good preservability and is tolerable in a heavy charge.
Inventors
- 👤 M Shuin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:55
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/02; H01M4/36; H01M4/48; H01M4/50; C; C25; C25B; C25B1/00; C25B1/01; C25B1/21; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
122 words
IN A PROCESS FOR PRODUCING MANGANESE DIOXIDE BY ELECTROLYSIS OF AN AQUEOUS SOLUTION CONTAINING SULFURIC ACID AND MANGANOUS SULFATE IN AN ELECTROLYTIC APPARATUS, WHOSE MEMBERS IN CONTACT WITH THE ELECTROLYTIC SOLUTION ARE MADE OF LEAD OR LEAD ALLOY, THE IMPROVEMENT COMPRISES A STEP OF SUBJECTING THE DEPOSITED MANGANESE DIOXIDE LAYERS HAVING LEAD OXIDE FILMS ON THEIR SURFACES PEELED OFF FROM AN ANODE TO MUTUAL ABRASION, THEREBY SUBSTANTIALLY REMOVING SAID FILMS FROM SAID LAYERS, AND A STEP OF COARSELY DIVIDING THE MANGANESE DIOXIDE LAYERS FROM WHICH SAID FILMS HAVE BEEN REMOVED IN THE PRECEDING STEP INTO PIECES OF 1 TO 15 MM IN PARTICLE DIAMETER, AND WASHING WITH WATER OR AN ALKALINE SOLUTION, THEREBY REMOVING A SULFATE ION-CONTAINING COMPOUND OCCLUDED IN SAID PIECES.
Claim 2
Dependent Claim
122 words
IN A PROCESS FOR PRODUCING MANGANESE DIOXIDE BY ELECTROLYSIS OF AN AQUEOUS SOLUTION CONTAINING SULFURIC ACID AND MANGANOUS SULFATE IN AN ELECTROLYTIC APPARATUS, WHOSE MEMBERS IN CONTACT WITH THE ELECTROLYTIC SOLUTION ARE MADE OF LEAD OR LEAD ALLOY, THE IMPROVEMENT COMPRISES A STEP OF SUBJECTING THE DEPOSITED MANGANESE DIOXIDE LAYERS HAVING LEAD OXIDE FILMS ON THEIR SURFACES PEELED OFF FROM AN ANODE TO MUTUAL ABRASION, THEREBY SUBSTANTIALLY REMOVING SAID FILMS FROM SAID LAYERS, AND A STEP OF COARSELY DIVIDING THE MANGANESE DIOXIDE LAYERS FROM WHICH SAID FILMS HAVE BEEN REMOVED IN THE PRECEDING STEP INTO PIECES OF 1 TO 15 MM IN PARTICLE DIAMETER, AND WASHING WITH WATER OR AN ALKALINE SOLUTION, THEREBY REMOVING A SULFATE ION-CONTAINING COMPOUND OCCLUDED IN SAID PIECES.
Claim 3
Dependent Claim
21 words
A process according to claim 1, wherein the mutual abrasion is carried out in the presence of water or hot water.
Claim 4
Dependent Claim
23 words
A process according to claim 1, wherein the washing with water is first effected and then the neutralization with alkaline solution is effected.
Claim 5
Dependent Claim
17 words
A process according to claim 1, wherein the alkaline solution used in the neutralization is ammonia water.
References Cited (Backward Citations)
US3455798A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-28 | 1978-04-29 | 1978-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-28 | 1982-04-29 | 1982-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-28 | 1986-04-29 | 1986-10-29 | $7700.00 | Window Closed / Lapsed |