US3295954A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for roasting materials containing chromium oxide
Assignee: Zahn and Co GmbH
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Filing: 1964-01-21
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Granted: 1967-01-03
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Expires: 1984-01-21
Abstract
No abstract record available.
Inventors
- 👤 Schatzler Friedrich
- 👤 Falk Klaus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:35
CPC Classifications
C; C22; C22B; C22B34/00; C22B34/30; C22B34/32; C01; C01G; C01G37/00; C01G37/14; C22B1/00; C22B1/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
110 words
A PROCESS FOR THE ALKALINE ROASTING OF MATERIALS CONTAINING CHROMIUM OXIDE BY MEANS OF ROASTING GASES ESSENTIALLY CONSISTING OF FORMING A MIXTURE OF SAID MATERIALS WITH A COMPOUND SELECTED FROM THE GROUP CONSISTING OF SODIUM CARBONATE AND CAUSTIC ALKALI, MOLDING THE RESULTING MIXTURE INTO CAKES AND CONVEYING THE CAKES, FREE FROM MECHANICAL STRESSES, ON A SUPPORT, IN COUNTER-CURRENT TO THE FLOW OF SAID ROASTING GASES, THROUGH A HEATED LONG REACTION SPACE OF SMALL HEIGHT, IN WHICH IS MAINTAINED A TEMPERATURE GRADIENT INCREASING IN THE DIRECTION OF ADVANCE OF THE MATERIAL TO BE ROASTED, UP TO A MAXIMUM TEMPERATURE WHICH IS LESS THAN THE MELTING AND SINTERING TEMPERATURE OF THE CAKES.
Claim 2
Dependent Claim
110 words
A PROCESS FOR THE ALKALINE ROASTING OF MATERIALS CONTAINING CHROMIUM OXIDE BY MEANS OF ROASTING GASES ESSENTIALLY CONSISTING OF FORMING A MIXTURE OF SAID MATERIALS WITH A COMPOUND SELECTED FROM THE GROUP CONSISTING OF SODIUM CARBONATE AND CAUSTIC ALKALI, MOLDING THE RESULTING MIXTURE INTO CAKES AND CONVEYING THE CAKES, FREE FROM MECHANICAL STRESSES, ON A SUPPORT, IN COUNTER-CURRENT TO THE FLOW OF SAID ROASTING GASES, THROUGH A HEATED LONG REACTION SPACE OF SMALL HEIGHT, IN WHICH IS MAINTAINED A TEMPERATURE GRADIENT INCREASING IN THE DIRECTION OF ADVANCE OF THE MATERIAL TO BE ROASTED, UP TO A MAXIMUM TEMPERATURE WHICH IS LESS THAN THE MELTING AND SINTERING TEMPERATURE OF THE CAKES.
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) | 1970-01-02 | 1970-07-04 | 1971-01-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-01-02 | 1974-07-04 | 1975-01-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-01-02 | 1978-07-04 | 1979-01-03 | $7700.00 | Window Closed / Lapsed |