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Patent US4313006A successfully refreshed from Google Patents.
US4313006A
Expired / Lapsed
US
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Process for converting dialkyl sulfides to alkyl mercaptans
Assignee: Arkema Inc
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Filing: 1980-09-03
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Granted: 1982-01-26
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Expires: 2000-09-03
Abstract
Abstract A process is provided for preparing alkyl mercaptans by reacting a dialkyl sulfide with hydrogen sulfide in the presence of a zeolite catalyst.
Inventors
- 👤 Robert B. Hager
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:58
CPC Classifications
C; C07; C07C; C07C321/00; C07C319/00; C07C319/02; C07C319/06
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
85 words
A continuous vapor-phase process for preparing high purity C 1 to C 18 alkyl mercaptan, RSH, comprising reacting dialkyl sulfide, R--S--R, where R is C 1 to C 18 alkyl or C 6 to C 18 cycloalkyl, with a molar excess of hydrogen sulfide in the presence of a zeolite catalyst at elevated temperatures not in excess of 390° C., said zeolite catalyst being Type X, Type Y, or Type L, and containing less than 10% by weight alkali metal, expresed as Na 2 O.
Claim 2
Dependent Claim
85 words
A continuous vapor-phase process for preparing high purity C 1 to C 18 alkyl mercaptan, RSH, comprising reacting dialkyl sulfide, R--S--R, where R is C 1 to C 18 alkyl or C 6 to C 18 cycloalkyl, with a molar excess of hydrogen sulfide in the presence of a zeolite catalyst at elevated temperatures not in excess of 390° C., said zeolite catalyst being Type X, Type Y, or Type L, and containing less than 10% by weight alkali metal, expresed as Na 2 O.
Claim 3
Dependent Claim
14 words
The process of claim 1, wherein R is C 1 to C 12 alkyl.
Claim 4
Dependent Claim
16 words
The process of claim 1 wherein R--S--R is crude, by-product from a methyl mercaptan manufacturing process.
Claim 5
Dependent Claim
15 words
The process of claim 1, wherein the catalyst temperature is in the range 250°-390° C.
Claim 6
Dependent Claim
18 words
The process of claim 4, wherein the pressure in the reaction zone ranges from atmospheric to 600 psig.
Claim 7
Dependent Claim
25 words
The process of claim 4, wherein the molar ratio of hydrogen sulfide to dialkyl sulfide supplied to the reaction zone ranges from 3:1 to 20:1.
Claim 8
Dependent Claim
34 words
The process of claim 4, wherein the rate at which the dialkyl sulfide is passed over the catalyst ranges from 10 to 300 gram-moles of dialkyl sulfide per kilogram of catalyst per 24 hours.
Claim 9
Dependent Claim
31 words
The process of claim 4, wherein the alkali metal content of the zeolite catalyst has been reduced below 10% by exchanging the alkali metal ions with protons or catalytically active cations.
Claim 10
Dependent Claim
39 words
The process of claim 4, wherein the alkali metal has been reduced below 10% by exchanging the alkali metal ions with ammonium ions and thereafter the zeolite is calcined to remove at least a major portion of the ammonia.
Claim 11
Dependent Claim
20 words
The process of claim 9, wherein the alkali metal content, expressed as Na 2 O, is below 3% by weight.
Claim 12
Dependent Claim
19 words
The process of claim 10, wherein the dialkyl sulfide is dimethyl sulfide and the reaction product is methyl mercaptan.
Claim 13
Dependent Claim
28 words
The process of claim 11, wherein the catalyst temperature is in the range 320°-390° C. and the pressure in the reaction zone is in the range 50-350 psig.
Claim 14
Dependent Claim
52 words
The process of claim 12, wherein the dimethyl sulfide is passed over the zeolite catalyst at a rate in the range of 20-150 gram-moles per kilogram of catalyst per 24 hours, and the molar ratio of hydrogen sulfide to dimethyl sulfide supplied to the reactor is in the range 5:1 to 15:1.
References Cited (Backward Citations)
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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) | 1985-01-25 | 1985-07-27 | 1986-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-01-25 | 1989-07-27 | 1990-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-01-25 | 1993-07-27 | 1994-01-26 | $7700.00 | Window Closed / Lapsed |