US4752456A
Expired / Lapsed
US
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Process for preparing metal carbides and precursors thereof
Assignee: Mitsui Chemicals Inc
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Filing: 1983-06-01
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Granted: 1988-06-21
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Expires: 2003-06-01
Abstract
Abstract PCT No. PCT/JP83/00180 Sec. 371 Date Jan. 27, 1984 Sec. 102(e) Date Jan. 27, 1984 PCT Filed Jun. 1, 1983 PCT Pub. No. WO83/04188 PCT Pub. Date Dec. 8, 1983.A carbon-containing mixture is obtained by collecting a dispersed phase mixture from an aerosol which has been formed by introducing a decomposable carbon compound and a decomposable metallic compound into a hot gas containing steam. Since this carbon-containing mixture is extremely high in uniformity and consists of extremely fine particles, it can afford after heat treatment a metal carbide of high quality.
Inventors
- 👤 Yukihiro Yoda
- 👤 Makoto Horita
- 👤 Kensaku Maruyama
- 👤 Hideaki Miyashita
- 👤 Norihiro Murakawa
- 👤 Kazuyoshi Isogaya
- 👤 Fumio Nakamura
- 👤 Norimasa Kawamura
- 👤 Noriaki Kuramitsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 06:57
CPC Classifications
C; C01; C01B; C01B32/00; C01B32/90; C01B32/914; C01B32/956; C01B32/907; C01B32/921; C01B32/949; C01B32/963; C01B32/97; C01B32/991; C01P; C01P2002/00; C01P2002/70; C01P2002/76; C01P2006/00; C01P2006/12; C01P2006/80
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
181 words
A process for preparing a carbon-containing mixture comprising elemental carbon and at least a metal oxide having the molar ratio of carbon to metal in the range of 3 to 20 suitable for the preparation of a metal carbide which comprises: (i) introducing a decomposable carbon compound which compound is a metal-free carbon compound capable of being decomposed to elemental carbon in a hot gas and a decomposable metallic compound which compound is a metallic compound capable of being decomposed in a hot gas containing steam to produce a corresponding metal oxide, into a hot gas containing steam, said carbon compound and said metallic compound being present in an amount sufficient to obtain said carbon to metal molar ratio of 3 to 20, (ii) decomposing said carbon compound to elemental carbon and said metallic compound to a metallic oxide by said hot gas in the presence of said steam, (iii) thereby producing said solid mixture of elemental carbon and a metal oxide dispersed in a gas phase, (iv) collecting said dispersed solid mixture from said gas phase by solid-gas separating means.
Claim 2
Dependent Claim
181 words
A process for preparing a carbon-containing mixture comprising elemental carbon and at least a metal oxide having the molar ratio of carbon to metal in the range of 3 to 20 suitable for the preparation of a metal carbide which comprises: (i) introducing a decomposable carbon compound which compound is a metal-free carbon compound capable of being decomposed to elemental carbon in a hot gas and a decomposable metallic compound which compound is a metallic compound capable of being decomposed in a hot gas containing steam to produce a corresponding metal oxide, into a hot gas containing steam, said carbon compound and said metallic compound being present in an amount sufficient to obtain said carbon to metal molar ratio of 3 to 20, (ii) decomposing said carbon compound to elemental carbon and said metallic compound to a metallic oxide by said hot gas in the presence of said steam, (iii) thereby producing said solid mixture of elemental carbon and a metal oxide dispersed in a gas phase, (iv) collecting said dispersed solid mixture from said gas phase by solid-gas separating means.
Claim 3
Dependent Claim
217 words
A process for preparing a metal carbide from a carbon-containing mixture comprising elemental carbon and at least a metal oxide having the molar ratio of carbon to metal in the range of 3 to 20 suitable for the preparation of a metal carbide which comprises: (i) introducing a decomposable carbon compound which compound is a metal free carbon compound capable of being decomposed to elemental carbon in a hot gas and a decomposable metallic compound which compound is a metallic compound capable of being decomposed in a hot gas containing steam to produce a corresponding metal oxide into a hot gas containing steam, said carbon compound and said metallic compound being present in an amount sufficient to obtain said carbon to metal molar ratio of 3 to 20. (ii) decomposing said carbon compound to elemental carbon and said metallic compound to a metallic oxide by said hot gas in the presence of said steam, (iii) thereby producing said solid mixture of elemental carbon and metal oxide dispersed in a gas phase, (iv) collecting said dispersed solid mixture from said gas phase by solid-gas separating means, (v) heating said carbon containing mixture in a furnace at a temperature in the range from about 1,300° C. to about 2,400° C. to convert said carbon-containing mixture to a metal carbide.
Claim 4
Dependent Claim
217 words
A process for preparing a metal carbide from a carbon-containing mixture comprising elemental carbon and at least a metal oxide having the molar ratio of carbon to metal in the range of 3 to 20 suitable for the preparation of a metal carbide which comprises: (i) introducing a decomposable carbon compound which compound is a metal free carbon compound capable of being decomposed to elemental carbon in a hot gas and a decomposable metallic compound which compound is a metallic compound capable of being decomposed in a hot gas containing steam to produce a corresponding metal oxide into a hot gas containing steam, said carbon compound and said metallic compound being present in an amount sufficient to obtain said carbon to metal molar ratio of 3 to 20. (ii) decomposing said carbon compound to elemental carbon and said metallic compound to a metallic oxide by said hot gas in the presence of said steam, (iii) thereby producing said solid mixture of elemental carbon and metal oxide dispersed in a gas phase, (iv) collecting said dispersed solid mixture from said gas phase by solid-gas separating means, (v) heating said carbon containing mixture in a furnace at a temperature in the range from about 1,300° C. to about 2,400° C. to convert said carbon-containing mixture to a metal carbide.
Claim 5
Dependent Claim
23 words
The process of claim 2, wherein the metal component is silicon, titanium, tungsten, boron, aluminum, zirconium, hafnium, niobium, molybdenum, tantalum, chromium, or vanadium.
Claim 6
Dependent Claim
27 words
The process of claim 2, wherein the metal component comprises silicon and boron, where the weight ratio of boron to silicon is in the range of 0.5-4.5:100.
Claim 7
Dependent Claim
41 words
The process of claim 2, wherein said carbon-containing mixture is compressed so as to give a bulk density thereof not lower than 0.15 g/cc and is heat-treated in this compressed state to obtain said metal carbide as a finely divided powder.
Claim 8
Dependent Claim
28 words
The process claim 2 wherein said carbon centaining mixture has a bulk density below 0.15 g/cc prior to heat treatment to produce said metal carbide in wisker form.
Claim 9
Dependent Claim
15 words
The process of claim 2 wherein the metal of said decomposable metallic compound is silicon.
Claim 10
Dependent Claim
23 words
The process of claim 1, wherein said decomposable carbon compound is a compound selected from the group consisting of hydrocarbons and halogenated hydrocarbons.
References Cited (Backward Citations)
US3123567A
Cited
US1868921A
Cited
US3077385A
Cited
US3340020A
Cited
US3383175A
Cited
GB1238346A
Cited
US3812239A
Cited
US3839542A
Cited
US4080431A
Cited
US4364974A
Cited
US4622215A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-06-21 | 1991-12-21 | 1992-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-21 | 1995-12-21 | 1996-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-21 | 1999-12-21 | 2000-06-21 | $7700.00 | Window Closed / Lapsed |