US4606902A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing refractory borides and carbides
Assignee: United States, COMMERCE THE, Secretary of
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Filing: 1985-10-03
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Granted: 1986-08-19
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Expires: 2005-10-03
Abstract
Abstract Refractory borides or carbides are prepared by contacting an alkali-metal ducible metal chloride or silicon tetrachloride with boron trichloride or carbon tetrachloride in an inert solvent in the presence of an alkali metal, the metal chloride or silicon tetrachloride and the boron trichloride or carbon tetrachloride being present in an amount about stoichiometrically equivalent to the boride or carbide to be prepared and the alkali metal being present in an amount about stoichiometrically equivalent to the amount of chloride in the metal chloride or silicon tetrachloride and the boron trichloride or carbon tetrachloride, until all chloride present has reacted with the alkali metal to form alkali metal chloride, separating the inert solvent to leave a solid residue containing a metal boride, silicon carbide or metal carbide precursor together with the alkali metal chloride, and calcining the residue while separating the alkali metal chloride until the precursor is converted to the refractory boride or carbide.
Inventors
- 👤 Joseph J. Ritter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:42
CPC Classifications
C; C01; C01B; C01B35/00; C01B35/02; C01B35/04; C01B32/00; C01B32/90; C01B32/914; C01B32/921; C01B32/956; C01B32/963; C01B32/991
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
181 words
A method for the preparation of a refractory boride or carbide which comprises contacting a metal chloride, said metal chloride undergoing reduction on reaction with an alkali metal, or silicon tetrachloride with boron trichloride or carbon tetrachloride in a solvent unreactive with said alkali metal and said chlorides in the presence of an alkali metal, said metal chloride or silicon tetrachloride and said boron trichloride or carbon tetrachloride being present in an amount about stoichiometrically equivalent to the boride or carbide to be prepared and said alkali metal being present in an amount about stoichiometrically equivalent to the amount of chloride in said metal chloride or silicon tetrachloride and said boron trichloride or carbon tetrachloride, until the aforesaid chlorides present have reacted with the alkali metal to form alkali metal chloride, separating the solvent to leave a solid residue containing a metal boride, silicon carbide or metal carbide precursor together with the alkali metal chloride, and heating the residue at about 700°-900° C. while separating the alkali metal chloride until the said precursor is converted to the refractory boride or carbide.
Claim 2
Independent Claim
181 words
A method for the preparation of a refractory boride or carbide which comprises contacting a metal chloride, said metal chloride undergoing reduction on reaction with an alkali metal, or silicon tetrachloride with boron trichloride or carbon tetrachloride in a solvent unreactive with said alkali metal and said chlorides in the presence of an alkali metal, said metal chloride or silicon tetrachloride and said boron trichloride or carbon tetrachloride being present in an amount about stoichiometrically equivalent to the boride or carbide to be prepared and said alkali metal being present in an amount about stoichiometrically equivalent to the amount of chloride in said metal chloride or silicon tetrachloride and said boron trichloride or carbon tetrachloride, until the aforesaid chlorides present have reacted with the alkali metal to form alkali metal chloride, separating the solvent to leave a solid residue containing a metal boride, silicon carbide or metal carbide precursor together with the alkali metal chloride, and heating the residue at about 700°-900° C. while separating the alkali metal chloride until the said precursor is converted to the refractory boride or carbide.
Claim 3
Independent Claim
151 words
A method for the preparation of a refractory boride which comprises contacting a metal chloride, said metal chloride undergoing reduction on reaction with an alkali metal, with boron trichloride in a solvent unreactive with said alkali metal and said chlorides in the presence of an alkali metal, the metal chloride and the boron trichloride being present in an amount about stoichiometrically equivalent to the boride to be prepared and said alkali metal being present in an amount about stoichiometrically equivalent to the amount of chloride in the metal chloride and the boron trichloride, until the aforesaid chlorides have reacted with the alkali metal to form alkali metal chloride, separating the solvent to leave a solid residue containing a metal boride precursor together with the alkali metal chloride, and heating the residue at about 600°-800° C. while separating the alkali metal chloride until the said precursor is converted to the refractory boride.
Claim 4
Independent Claim
151 words
A method for the preparation of a refractory boride which comprises contacting a metal chloride, said metal chloride undergoing reduction on reaction with an alkali metal, with boron trichloride in a solvent unreactive with said alkali metal and said chlorides in the presence of an alkali metal, the metal chloride and the boron trichloride being present in an amount about stoichiometrically equivalent to the boride to be prepared and said alkali metal being present in an amount about stoichiometrically equivalent to the amount of chloride in the metal chloride and the boron trichloride, until the aforesaid chlorides have reacted with the alkali metal to form alkali metal chloride, separating the solvent to leave a solid residue containing a metal boride precursor together with the alkali metal chloride, and heating the residue at about 600°-800° C. while separating the alkali metal chloride until the said precursor is converted to the refractory boride.
Claim 5
Dependent Claim
12 words
A method according to claim 2, wherein the alkali metal is sodium.
Claim 6
Dependent Claim
15 words
A method according to claim 2, wherein the metal chloride is a transition metal chloride.
Claim 7
Dependent Claim
13 words
A method according to claim 4, wherein the metal chloride is titanium tetrachloride.
Claim 8
Dependent Claim
19 words
A method according to claim 2, wherein the solvent is an aliphatic hydrocarbon, an aromatic hydrocarbon or an ether.
Claim 9
Dependent Claim
11 words
A method according to claim 6, wherein the solvent is heptane.
Claim 10
Dependent Claim
12 words
A method according to claim 2, wherein heating is at 800° C.
Claim 11
Dependent Claim
15 words
A method according to claim 2, wherein the reaction is effected in an inert atmosphere.
Claim 12
Independent Claim
163 words
A method for the preparation of a refractory carbide which comprises contacting silicon tetrachloride or a metal chloride, said metal chloride undergoing reduction on reaction with an alkali metal, with carbon tetrachloride in a solvent unreactive with said alkali metal and said chlorides in the presence of an alkali metal, silicon tetrachloride or said metal chloride and said carbon tetrachloride being present in an amount about stoichiometrically equivalent to the carbide to be prepared and said alkali metal being present in an amount about stoichiometrically equivalent to the amount of chloride in said silicon tetrachloride or said metal chloride and said carbon tetrachloride, until the aforesaid chlorides have reacted with the alkali metal to form alkali metal chloride, separating the solvent to leave a solid residue containing silicon carbide or metal carbide precursor together with the alkali metal chloride, and heating the residue at about 700°-900° C. while separating the alkali metal chloride until the said precursor is converted to the refractory carbide.
Claim 13
Independent Claim
163 words
A method for the preparation of a refractory carbide which comprises contacting silicon tetrachloride or a metal chloride, said metal chloride undergoing reduction on reaction with an alkali metal, with carbon tetrachloride in a solvent unreactive with said alkali metal and said chlorides in the presence of an alkali metal, silicon tetrachloride or said metal chloride and said carbon tetrachloride being present in an amount about stoichiometrically equivalent to the carbide to be prepared and said alkali metal being present in an amount about stoichiometrically equivalent to the amount of chloride in said silicon tetrachloride or said metal chloride and said carbon tetrachloride, until the aforesaid chlorides have reacted with the alkali metal to form alkali metal chloride, separating the solvent to leave a solid residue containing silicon carbide or metal carbide precursor together with the alkali metal chloride, and heating the residue at about 700°-900° C. while separating the alkali metal chloride until the said precursor is converted to the refractory carbide.
Claim 14
Dependent Claim
12 words
A method according to claim 10, wherein the alkali metal is sodium.
Claim 15
Dependent Claim
18 words
A method according to claim 10, wherein the metal chloride is a Group IVB, VB or VIB chloride.
Claim 16
Dependent Claim
19 words
A method according to claim 10, wherein the solvent is an apliphatic hydrocarbon, an aromatic hydrocarbon or an ether.
Claim 17
Dependent Claim
11 words
A method according to claim 13, wherein the solvent is heptane.
Claim 18
Dependent Claim
12 words
A method according to claim 10, wherein heating is at 800° C.
Claim 19
Dependent Claim
15 words
A method according to claim 10, wherein the reaction is effected in an inert atmosphere.
Claim 20
Dependent Claim
12 words
A method according to claim 10, wherein the carbide is silicon carbide.
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) | 1989-08-18 | 1990-02-17 | 1990-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-08-18 | 1994-02-17 | 1994-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-08-18 | 1998-02-17 | 1998-08-19 | $7700.00 | Window Closed / Lapsed |