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US5001269A
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Process for the production of lower dialkyl disulphides
Assignee: Societe Nationale Elf Aquitaine Production SA
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Filing: 1989-04-03
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Granted: 1991-03-19
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Expires: 2009-04-03
Abstract
Abstract The invention relates to the production of dialkyl disulphides of the R-SS-R type where R represents an alkyl radical having from 1 to 3 carbon atoms, by oxidation of the corresponding alkyl mercaptan R--SH by sulphur in the presence of a catalyst. A combination of an alkyl mercantap R'--SH with an alkylene oxide and an alkaline base is used as catalyst, R' representing an alkyl radical having from 6 to 18 carbon atoms. This catalyst enables a lower dialkyl disulphide of excellent quality to be obtained (absence of amine and coloration).
Inventors
- 👤 Henri Gongora
- 👤 Yves Darche
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:44
CPC Classifications
C; C07; C07C; C07C319/00; C07C319/22; C07C319/24; C07C321/00; C07C321/12; C07C321/14
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
154 words
A process for the production of a lower dialkyl disulphide of formula R--SS--R where R represents an alkyl radical having from 1 to 3 carbon atoms, comprising oxidation of the corresponding alkyl mercaptan RSH with sulphur in the presence of a catalyst, the catalyst used is a combination of a higher alkyl mercaptan R'--SH with an alkylene oxide C n H 2n O and an alkaline base MOH, this combination is represented by the formula R'--SH.x(C.sub.n H.sub.2n O).yMOH in which R' is a linear or a branched alkyl radical containing from 6 to 18 carbon atoms, n is a number in the range 2 to 4, x is a number in the range 1 to 20, y is a number in the range 0.01 to 1 and M represents an alkali metal atom whereby the dialkyl disulphide is substantially devoid of amine impurities and very weakly colored and the catalyst being recoverable and recyclable.
Claim 2
Dependent Claim
154 words
A process for the production of a lower dialkyl disulphide of formula R--SS--R where R represents an alkyl radical having from 1 to 3 carbon atoms, comprising oxidation of the corresponding alkyl mercaptan RSH with sulphur in the presence of a catalyst, the catalyst used is a combination of a higher alkyl mercaptan R'--SH with an alkylene oxide C n H 2n O and an alkaline base MOH, this combination is represented by the formula R'--SH.x(C.sub.n H.sub.2n O).yMOH in which R' is a linear or a branched alkyl radical containing from 6 to 18 carbon atoms, n is a number in the range 2 to 4, x is a number in the range 1 to 20, y is a number in the range 0.01 to 1 and M represents an alkali metal atom whereby the dialkyl disulphide is substantially devoid of amine impurities and very weakly colored and the catalyst being recoverable and recyclable.
Claim 3
Dependent Claim
21 words
The process according to claim 1, wherein R' is a C 8 -C 16 tertiary alkyl radical, preferably tert-nonyl or tertdodecyl.
Claim 4
Dependent Claim
25 words
The process according to claim 1, wherein n is equal to 2, x is between 4 and 12 and y is between 0.1 and 0.5.
Claim 5
Dependent Claim
37 words
The process according to claim 1, wherein the catalyst is used in a quantity of 0.2 to 5% in relation to the weight of sulphur added, the molar ratio mercaptan RSH/sulphur being at least equal to 2.
Claim 6
Dependent Claim
17 words
The process according to claim 1, wherein the molar ratio mercaptan RSH/sulphur is between 3 and 5.
Claim 7
Dependent Claim
34 words
The process according to claim 1, wherein the reaction is carried out at a temperature in the range 25° to 125° C. and under an effective pressure in the range 1 to 5 bars.
Claim 8
Dependent Claim
26 words
The process according to claim 6, wherein the temperature range is between 50° and 80° C. and the pressure range is between 3 and 4 bars.
Claim 9
Dependent Claim
23 words
The process according to claim 1, wherein operation is continuous, residence time in the reactor is in the range 20 to 180 minutes.
Claim 10
Dependent Claim
16 words
The process according to claim 8, wherein the residence time is between 30 and 90 minutes.
Claim 11
Dependent Claim
14 words
The process according to claim 1, wherein the alkyl mercaptan RSH is methyl mercaptan.
References Cited (Backward Citations)
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Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-03-18 | 1994-09-17 | 1995-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-03-18 | 1998-09-17 | 1999-03-19 | $3760.00 | Window Closed / Lapsed |
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