Patent US5780101A successfully refreshed from Google Patents.
US5780101A
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Method for producing encapsulated nanoparticles and carbon nanotubes using catalytic disproportionation of carbon monoxide
Assignee: University of Arizona
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Filing: 1995-02-17
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Granted: 1998-07-14
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Expires: 2015-02-17
Abstract
Abstract A method for the production of carbon encapsulated nanoparticles, carbon nanotubes and other closed carbon structures, including contacting a catalyst of a transition metal, or a compound or alloy thereof, with a gas mixture containing carbon monoxide, and an amount of available molecular hydrogen which is insufficient to cause formation of graphite plane edges through capping, at a temperature in the range from 300°-1000° C., to provide closed carbon structures, which are useful in the preparation of thermal composites, reinforcement composites and magnetic particle recording media.
Inventors
- 👤 Peter E. Nolan
- 👤 Andrew H. Cutler
- 👤 David G. Lynch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:07
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/22; C23C16/26; B; B82; B82Y; B82Y30/00; B82Y40/00; C01; C01B; C01B32/00; C01B32/15; C01B32/158; C01B32/16; C01B32/162; Y; Y10; Y10S; Y10S423/00; Y10S423/40; Y10S977/00; Y10S977/70; Y10S977/832; Y10S977/838; Y10S977/84; Y10S977/842; Y10T; Y10T428/00; Y10T428/30
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
154 words
A method for the production of carbon encapsulated metal particles and carbon nanotubes comprising: 1) drying a catalyst of a transition metal, or a compound or alloy thereof, in an inert gas at a temperature and for a period of time sufficient to form a dried catalyst; 2) reducing said dried catalyst with hydrogen to form a reduced catalyst; 3) contacting said reduced catalyst with an inert gas under conditions effective to reduce the level of residual hydrogen therein to less than about 5×10 -4 mol of H 2 equivalent per gram of catalyst, and then 4) contacting the catalyst from step (3) with a gas mixture containing carbon monoxide, and an amount of available molecular hydrogen which is insufficient to cause formation of graphite plane edges through capping, at a temperature in the range of from 300°-1000° C., to thereby form carbon nanotubes and metal particles of said catalyst which are carbon encapsulated.
Claim 2
Independent Claim
154 words
A method for the production of carbon encapsulated metal particles and carbon nanotubes comprising: 1) drying a catalyst of a transition metal, or a compound or alloy thereof, in an inert gas at a temperature and for a period of time sufficient to form a dried catalyst; 2) reducing said dried catalyst with hydrogen to form a reduced catalyst; 3) contacting said reduced catalyst with an inert gas under conditions effective to reduce the level of residual hydrogen therein to less than about 5×10 -4 mol of H 2 equivalent per gram of catalyst, and then 4) contacting the catalyst from step (3) with a gas mixture containing carbon monoxide, and an amount of available molecular hydrogen which is insufficient to cause formation of graphite plane edges through capping, at a temperature in the range of from 300°-1000° C., to thereby form carbon nanotubes and metal particles of said catalyst which are carbon encapsulated.
Claim 3
Dependent Claim
30 words
The method of claim 1, wherein said catalyst is a member selected from the group consisting of the Group VIII metals of the Periodic Table and compounds and alloys thereof.
Claim 4
Dependent Claim
26 words
The method of claim 1, wherein said catalyst is a member selected from the group consisting of Ni, Co, Fe, Ru and compounds and alloys thereof.
Claim 5
Dependent Claim
12 words
The method of claim 1, wherein said catalyst is a supported catalyst.
Claim 6
Dependent Claim
23 words
The method of claim 4, wherein said catalyst is a member selected from the group consisting of Ni, Co, Fe and Ru metals.
Claim 7
Dependent Claim
19 words
The method of claim 1, wherein said catalyst is Ni metal supported on a support of Kieselguhr or silica-alumina.
Claim 8
Dependent Claim
15 words
The method of claim 1, wherein said catalyst is cobalt supported on alumina or silica.
Claim 9
Dependent Claim
27 words
The method of claim 1, wherein said gas mixture comprises carbon monoxide, carbon dioxide and ≦0.1 mol % of available hydrogen as hydrogen gas or hydrocarbon gas.
Claim 10
Dependent Claim
32 words
The method of claim 8, wherein carbon monoxide and carbon dioxide are present in a CO/CO 2 ratio sufficient to provide a carbon activity, a c , of from 10 to 50.
Claim 11
Dependent Claim
18 words
The method of claim 1, wherein said gas mixture contains no hydrogen as hydrogen gas or hydrocarbon gas.
Claim 12
Dependent Claim
15 words
The method of claim 1, wherein said temperature in step 4 is from 300°-800° C.
Claim 13
Dependent Claim
15 words
The method of claim 1, wherein said temperature in step 4 is from 500-700° C.
Claim 14
Dependent Claim
37 words
The method of claim 1, wherein said drying of said catalyst is carried out in an inert gas at a temperature of from 300° to 800° C, for a period of time from 1 to 5 h.
Claim 15
Dependent Claim
17 words
The method of claim 1, wherein said method provides carbon encapsulated metal nanoparticles as a major product.
Claim 16
Dependent Claim
15 words
The method of claim 1, wherein said method provides carbon nanotubes as a major product.
Claim 17
Dependent Claim
22 words
The method of claim 1, wherein said method is performed for a period of time of from 1 h to 4 days.
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) | 2001-07-13 | 2002-01-12 | 2002-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-07-13 | 2006-01-12 | 2006-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-07-13 | 2010-01-12 | 2010-07-14 | $7700.00 | Window Closed / Lapsed |