Patent US1230830A successfully refreshed from Google Patents.
Patent US4684399A successfully refreshed from Google Patents.
US4684399A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tantalum powder process
Assignee: Cabot Corp
•
Filing: 1986-09-29
•
Granted: 1987-08-04
•
Expires: 2006-09-29
Abstract
Abstract A reduction process for producing tantalum powder wherein a tantalum compound is introduced, in a continuous or incremental manner, to a reactor, during the course of the reduction reaction.
Inventors
- 👤 Roger M. Bergman
- 👤 Charles E. Mosheim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:31
CPC Classifications
H; H01; H01G; H01G9/00; H01G9/004; H01G9/04; H01G9/048; H01G9/052; B; B22; B22F; B22F9/00; B22F9/16; B22F9/18; B22F9/24; C; C22; C22B; C22B34/00; C22B34/20; C22B34/24; C22B5/00; C22B5/02; C22B5/04
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
52 words
In a process for producing capacitor grade tantalum powder wherein a tantalum compound is reduced to tantalum metal by reaction with a reducing metal, the improvement characterized by introducing the tantalum compound and the reducing metal in a continuous or incremental manner to the reactor during the course of the reduction reaction.
Claim 2
Dependent Claim
52 words
In a process for producing capacitor grade tantalum powder wherein a tantalum compound is reduced to tantalum metal by reaction with a reducing metal, the improvement characterized by introducing the tantalum compound and the reducing metal in a continuous or incremental manner to the reactor during the course of the reduction reaction.
Claim 3
Dependent Claim
21 words
The process of claim 1 wherein the tantalum compound is selected from potassium fluotantalate, sodium fluotantalate, tantalum chloride, and mixtures thereof.
Claim 4
Dependent Claim
17 words
The process of claim 1 wherein the reducing metal is selected from sodium, potassium, and mixtures thereof.
Claim 5
Dependent Claim
17 words
The process of claim 1 wherein potassium fluotantalate is reduced to tantalum metal by reaction with sodium.
Claim 6
Dependent Claim
31 words
The process of claim 4 wherein the potassium fluotantalate is introduced into the reactor in increments ranging from about one half to about one twentieth of the total tantalum compound charge.
Claim 7
Dependent Claim
29 words
The process of claim 1 wherein sodium is introduced at a rate ranging from about 0.2 to about 15.0 pounds (0.09 to about 6.80 kg) per minute (60 seconds).
Claim 8
Dependent Claim
27 words
The process of claim 4 wherein the reduction reaction is maintained at a temperature ranging from about 600° to about 950° C. (873° to about 1223° K).
Claim 9
Dependent Claim
46 words
In a process for producing columbium powder wherein a columbium compound is reduced to columbium metal by reaction with a reducing metal, the improvement characterized by introducing the columbium compound in a continuous or incremental manner to the reactor during the course of the reduction reaction.
Claim 10
Dependent Claim
46 words
In a process for producing columbium powder wherein a columbium compound is reduced to columbium metal by reaction with a reducing metal, the improvement characterized by introducing the columbium compound in a continuous or incremental manner to the reactor during the course of the reduction reaction.
Claim 11
Dependent Claim
51 words
In a process for producing capacitor grade tantalum powder wherein a tantalum compound is reduced to tantalum metal by reaction with a reducing metal, the improvement characterized by introducing a solid tantalum compound in a continuous or incremental manner to the reactor with agitation during the course of the reduction reaction.
Claim 12
Dependent Claim
51 words
In a process for producing capacitor grade tantalum powder wherein a tantalum compound is reduced to tantalum metal by reaction with a reducing metal, the improvement characterized by introducing a solid tantalum compound in a continuous or incremental manner to the reactor with agitation during the course of the reduction reaction.
Claim 13
Dependent Claim
27 words
The process of claim 9 wherein the reducing metal is introduced to the reaction mixture as a unitary charge prior to the introduction of the tantalum compound.
References Cited (Backward Citations)
JPS4325910Y1
Cited
US4141720A
Cited
US4149876A
Cited
US4445931A
Cited
US4537641A
Cited
US4582530A
Cited
US4508563A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-03 | 1991-02-02 | 1991-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-03 | 1995-02-02 | 1995-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-03 | 1999-02-02 | 1999-08-04 | $7700.00 | Window Closed / Lapsed |