US2899296A
Expired / Lapsed
US
⏱️ 0.0 years remaining
kreimeier
Assignee: —
•
Filing: —
•
Granted: 1959-08-11
•
Expires: 1976-08-11
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:58
CPC Classifications
C; C22; C22B; C22B13/00; C22B13/02; C22B13/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
140 words
THE PROCESS FOR RECOVERING METALLIC LEAD FROM BYPRODUCT LEAD MATERIALS WHICH CONTAIN LEAD COMPOUNDS AND WHICH ARE OF THE CHARACTER OF THOSE OBTAINED IN THE MANUFACTURE OF TETRAETHYLLEAD, WHICH PROCESS COMPRISES HEATING SAID BY-PRODUCT LEAD MATERIALS AT A TEMPERATURE IN THE RANGE OF FROM ABOUT 400*C. TO ABOUT 850*C. IN THE PRESENCE OF A MEMBER OF THE GROUP CONSISTING OF SODIUM CYANIDE, POTASSIUM CYANIDE, MIXTURES OF SODIUM CYANIDE AND POTASSIUM CYANIDE, AND MIXTURES OF ANY OF SAID CYANIDES WITH A HYDROXIDE OF A CORRESPONDING ALKALI METAL, THE TEMPERATURE BEING SUFFICIENT TO MAINTAIN SAID MEMBER IN A MOLTEN STATE AND THE ALKALI METAL CYANIDE BEING PRESENT IN A PROPORTION CORRESPONDING TO AT LEAST ABOUT 20% EXCESS OVER THAT THEORETICALLY REQUIRED TO REACT WITH SAID LEAD COMPOUNDS AND CONVERT THEM TO METALLIC LEAD, AND SEPARATING MOLTEN METALLIC LEAD FROM THE REACTION MIXTURE.
Claim 2
Dependent Claim
140 words
THE PROCESS FOR RECOVERING METALLIC LEAD FROM BYPRODUCT LEAD MATERIALS WHICH CONTAIN LEAD COMPOUNDS AND WHICH ARE OF THE CHARACTER OF THOSE OBTAINED IN THE MANUFACTURE OF TETRAETHYLLEAD, WHICH PROCESS COMPRISES HEATING SAID BY-PRODUCT LEAD MATERIALS AT A TEMPERATURE IN THE RANGE OF FROM ABOUT 400*C. TO ABOUT 850*C. IN THE PRESENCE OF A MEMBER OF THE GROUP CONSISTING OF SODIUM CYANIDE, POTASSIUM CYANIDE, MIXTURES OF SODIUM CYANIDE AND POTASSIUM CYANIDE, AND MIXTURES OF ANY OF SAID CYANIDES WITH A HYDROXIDE OF A CORRESPONDING ALKALI METAL, THE TEMPERATURE BEING SUFFICIENT TO MAINTAIN SAID MEMBER IN A MOLTEN STATE AND THE ALKALI METAL CYANIDE BEING PRESENT IN A PROPORTION CORRESPONDING TO AT LEAST ABOUT 20% EXCESS OVER THAT THEORETICALLY REQUIRED TO REACT WITH SAID LEAD COMPOUNDS AND CONVERT THEM TO METALLIC LEAD, AND SEPARATING MOLTEN METALLIC LEAD FROM THE REACTION MIXTURE.
References Cited (Backward Citations)
US890160A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-08-10 | 1963-02-09 | 1963-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-08-10 | 1967-02-09 | 1967-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-08-10 | 1971-02-09 | 1971-08-11 | $7700.00 | Window Closed / Lapsed |