Patent US4595412A successfully refreshed from Google Patents.
US4595412A
Expired / Lapsed
US
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Production of molybdenum metal
Assignee: Osram Sylvania Inc
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Filing: 1985-07-22
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Granted: 1986-06-17
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Expires: 2005-07-22
Abstract
Abstract A process is disclosed for producing molybdenum metal from an ammonium molybdate salt. The process involves heating the salt in a reducing atmosphere at a temperature of no greater than about 775° C. for a sufficient time to convert the major portion of the salt to molybdenum dioxide, and heating the molybdenum dioxide in a reducing atmosphere at a temperature of no greater than about 1095° C. to convert the major portion of the molybdenum dioxide to molybdenum metal.
Inventors
- 👤 Timothy A. Brunelli
- 👤 Keith E. Landmesser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:46
CPC Classifications
B; B22; B22F; B22F9/00; B22F9/16; B22F9/18; B22F9/20; B22F9/22; C; C22; C22B; C22B34/00; C22B34/30; C22B34/34; C22B5/00; C22B5/02; C22B5/12
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
77 words
A process for producing molybdenum metal from an ammonium molybdate salt comprising: (a) heating said salt in a reducing atmosphere at a temperature of no greater than about 775° C. for a sufficient time to convert the major portion of said salt to molybdenum dioxide; and (b) heating said molybdenum dioxide in a reducing atmosphere at a temperature of no greater than about 1095° C. to convert the major portion of said molybdenum dioxide to molybdenum metal.
Claim 2
Dependent Claim
77 words
A process for producing molybdenum metal from an ammonium molybdate salt comprising: (a) heating said salt in a reducing atmosphere at a temperature of no greater than about 775° C. for a sufficient time to convert the major portion of said salt to molybdenum dioxide; and (b) heating said molybdenum dioxide in a reducing atmosphere at a temperature of no greater than about 1095° C. to convert the major portion of said molybdenum dioxide to molybdenum metal.
Claim 3
Dependent Claim
32 words
A process according to claim 1 wherein said salt is reduced to molybdenum dioxide in an atmosphere which consists essentially of about 75 mole percent hydrogen and about 25 mole percent nitrogen.
Claim 4
Dependent Claim
19 words
A process according to claim 1 wherein said molybdenum dioxide is reduced to molybdenum metal in a hydrogen atmosphere.
Claim 5
Dependent Claim
23 words
A process according to claim 1 wherein said salt is heated at a temperature of from about 540° C. to about 775° C.
Claim 6
Dependent Claim
24 words
A process according to claim 1 wherein said molybdenum dioxide is heated at a temperature of from about 845° C. to about 1000° C.
Claim 7
Dependent Claim
24 words
A process according to claim 1 wherein the average particle size of the molybdenum metal is from about 1 micron to about 4 microns.
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) | 1989-06-16 | 1989-12-16 | 1990-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-16 | 1993-12-16 | 1994-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-16 | 1997-12-16 | 1998-06-17 | $7700.00 | Window Closed / Lapsed |