Patent US4389389A successfully refreshed from Google Patents.
US4389389A
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Process for preparation of high purity tellurium
Assignee: Xerox Corp
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Filing: 1982-08-02
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Granted: 1983-06-21
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Expires: 2002-08-02
Abstract
Abstract This invention is generally directed to an improved process for the preparation of tellurium in high purity which comprises reacting tellurium dioxides, with a diol, and subjecting the resulting tellurium ester, subsequent to purification, to a reduction reaction.
Inventors
- 👤 Santokh S. Badesha
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:20
CPC Classifications
C; C01; C01B; C01B19/00; C01B19/02; C01P; C01P2002/00; C01P2002/80; C01P2002/82; C01P2002/84; C01P2002/86; C01P2002/89; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/582
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
31 words
A process for the preparation of tellurium of high purity which comprises reacting tellurium dioxides, with a diol, and subjecting the resulting tellurium ester, subsequent to purification, to a reduction reaction.
Claim 2
Dependent Claim
31 words
A process for the preparation of tellurium of high purity which comprises reacting tellurium dioxides, with a diol, and subjecting the resulting tellurium ester, subsequent to purification, to a reduction reaction.
Claim 3
Dependent Claim
22 words
A process in accordance with claim 1 wherein the tellurium dioxide results from the reaction of crude tellurium with a strong acid.
Claim 4
Dependent Claim
14 words
A process in accordance with claim 2 wherein the strong acid is nitric acid.
Claim 5
Dependent Claim
18 words
A process in accordance with claim 1, wherein the diol is an aliphatic glycol, or an aromatic glycol.
Claim 6
Dependent Claim
47 words
A process in accordance with claim 4 wherein the aliphatic glycol is of the formula HO(CR.sub.l R).sub.n OH wherein R is hydrogen or an alkyl group containing from about 1 to about 30 carbon atoms, and n is a number of from about 1 to about 10.
Claim 7
Dependent Claim
26 words
A process in accordance with claim 5 wherein R 1 and R 2 are an alkyl group containing from about 1 to about 6 carbon atoms.
Claim 8
Dependent Claim
13 words
A process in accordance with claim 5 wherein the glycol is ethylene glycol.
Claim 9
Dependent Claim
56 words
A process in accordance with claim 4 wherein the aromatic diol is of the formula ##STR3## wherein R 3 , R 4 , R 5 , and R 6 , are independently selected from hydrogen or an alkyl group containing about 1 carbon atom to about 30 carbon atoms, and Z is an aromatic ring group.
Claim 10
Dependent Claim
35 words
A process in accordance with claim 8 wherein Z is benzene, and R 3 , R 4 , and R 5 are alkyl groups containing from about 1 carbon atom to about 6 carbon atoms.
Claim 11
Dependent Claim
37 words
A process in accordance with claim 1 wherein the tellurium ester resulting from the reaction of the tellurium oxides with a diol is of the formula ##STR4## wherein R is an aliphatic group or an aromatic group.
Claim 12
Dependent Claim
16 words
A process in accordance with claim 1 wherein the reducing agent is sulphur dioxide or hydrazine.
Claim 13
Dependent Claim
25 words
A process in accordance with claim 1 wherein the reduction reaction is accomplished at a temperature of from about 25° C. to about 100° C.
Claim 14
Dependent Claim
17 words
A process in accordance with claim 1 wherein tellurium is obtained in a purity of 99.999 percent.
Claim 15
Dependent Claim
26 words
A process in accordance with claim 1 wherein the strong acid is separated from the acid tellurium oxide mixture by distillation, and recycled for subsequent use.
Claim 16
Dependent Claim
24 words
A process in accordance with claim 1 wherein the diol is separated from the tellurium ester mixture by distillation and recycled for subsequent use.
Claim 17
Dependent Claim
40 words
A process for preparing tellurium in high purity which comprises reacting tellurium tetrachloride with an aliphatic alcohol in the presence of an alkoxide, corresponding to the alcohol, and subjecting subsequent to purification the resulting tellurium ester to a reduction reaction.
Claim 18
Dependent Claim
40 words
A process for preparing tellurium in high purity which comprises reacting tellurium tetrachloride with an aliphatic alcohol in the presence of an alkoxide, corresponding to the alcohol, and subjecting subsequent to purification the resulting tellurium ester to a reduction reaction.
Claim 19
Dependent Claim
32 words
A process in accordance with claim 16 wherein the alcohol selected is of the formula ROH, wherein R is an alkyl group containing from 1 carbon atom to about 30 carbon atoms.
Claim 20
Dependent Claim
26 words
A process in accordance with claim 17 wherein the resulting ester is a tetraalkoxytellurane of the formula (RO) 4 Te, wherein R is an alkyl group.
Claim 21
Dependent Claim
13 words
A process in accordance with claim 18 wherein R is methylene or ethylene.
Claim 22
Dependent Claim
19 words
A process in accordance with claim 16 wherein the aliphatic alcohol is ethanol, and the alkoxide is sodium ethoxide.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-06-20 | 1986-12-20 | 1987-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-06-20 | 1990-12-20 | 1991-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-06-20 | 1994-12-20 | 1995-06-21 | $7700.00 | Window Closed / Lapsed |