US2853378A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treatment of lead
Assignee: EIDP Inc
•
Filing: 1957-08-19
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Granted: 1958-09-23
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Expires: 1977-08-19
Abstract
No abstract record available.
Inventors
- 👤 Edwin L Mattison
- 👤 Bernard N Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:13
CPC Classifications
C; C22; C22B; C22B13/00; C22B13/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
76 words
THE PROCESS FOR REDUCING THE AMOUNT OF SULFUR COMPOUNDS IN LEAD WHICH IS CONTAMINATED WITH FROM ABOUT 0.05% TO ABOUT 15% BY WEIGHT OF IMPURITIES WHICH CONSIST MAINLY OF LEAD SULFIDE, WHICH PROCESS COMPRISES MAINTAINING THE LEAD AT A TEMPERATURE OF FROM ABOUT 330*C. TO ABOUT 650*C. WHILE INTIMATELY CONTACTING IT WITH A MEMBER OF THE GROUP CONSISTING OF HYDROGEN CHLORIDE AND AMMONIUM CHLORIDE UNTIL THE HYDROGEN SULFIDE CONTENT OF THE OFF GAS BECOMES SUBSTANTIALLY NIL.
Claim 2
Dependent Claim
76 words
THE PROCESS FOR REDUCING THE AMOUNT OF SULFUR COMPOUNDS IN LEAD WHICH IS CONTAMINATED WITH FROM ABOUT 0.05% TO ABOUT 15% BY WEIGHT OF IMPURITIES WHICH CONSIST MAINLY OF LEAD SULFIDE, WHICH PROCESS COMPRISES MAINTAINING THE LEAD AT A TEMPERATURE OF FROM ABOUT 330*C. TO ABOUT 650*C. WHILE INTIMATELY CONTACTING IT WITH A MEMBER OF THE GROUP CONSISTING OF HYDROGEN CHLORIDE AND AMMONIUM CHLORIDE UNTIL THE HYDROGEN SULFIDE CONTENT OF THE OFF GAS BECOMES SUBSTANTIALLY NIL.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-09-22 | 1962-03-24 | 1962-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-09-22 | 1966-03-24 | 1966-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-09-22 | 1970-03-24 | 1970-09-23 | $7700.00 | Window Closed / Lapsed |