US3965207A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selective production of para-xylene
Assignee: Mobil Oil AS
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Filing: 1975-01-06
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Granted: 1976-06-22
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Expires: 1995-01-06
Abstract
Abstract Process for the selective production of paraxylene by methylation of toluene at a temperature between about 500 DEG C. and about 750 DEG C. and preferably between about 575 DEG C. and about 700 DEG C. in the presence of a catalyst comprising a crystalline aluminosilicate zeolite said zeolite having a silica to alumina mole ratio of at last about 12 and a constraint index, as hereinafter defined, within the approximate range of 1 to 12.
Inventors
- 👤 Benjamin Weinstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 01:32
CPC Classifications
C; C07; C07C; C07C2/00; C07C2/86; C07C2/862; C07C2/865; C01; C01B; C01B33/00; C01B33/20; C01B33/26; C01B33/28; C01B33/2807; C01B33/2876; C07C2/861; C07C2/864; C07C2/868; C07C2529/00; C07C2529/04; C07C2529/06; C07C2529/40; Y; Y10; Y10S; Y10S208/00; Y10S208/02
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
61 words
A process for the selective production of para-xylene which comprises reacting toluene with a methylating agent at a temperature between about 575°C and about 750°C in the presence of a catalyst comprising a crystalline aluminosilicate zeolite, said zeolite having a silica to alumina ratio of at least about 12 and a constraint index within the approximate range of 1 to 12.
Claim 2
Dependent Claim
61 words
A process for the selective production of para-xylene which comprises reacting toluene with a methylating agent at a temperature between about 575°C and about 750°C in the presence of a catalyst comprising a crystalline aluminosilicate zeolite, said zeolite having a silica to alumina ratio of at least about 12 and a constraint index within the approximate range of 1 to 12.
Claim 3
Dependent Claim
11 words
The process of claim 1 wherein said methylating agent is methanol.
Claim 4
Dependent Claim
20 words
The process of claim 2 wherein the molar ratio of methanol to toluene is between about 0.1 and about 2.
Claim 5
Dependent Claim
23 words
The process of claim 1 wherein said reacting takes place at a weight hourly space velocity of between about 5 and about 1500.
Claim 6
Dependent Claim
61 words
A process for the selective production of paraxylene which comprises reacting toluene with a methylating agent at a temperature between about 575°C. and about 700°C. in the presence of a catalyst comprising a crystalline aluminosilicate zeolite said zeolite having a silica to alumina ratio of at least about 12 and a constraint index within the approximate range of 1 to 12.
Claim 7
Dependent Claim
61 words
A process for the selective production of paraxylene which comprises reacting toluene with a methylating agent at a temperature between about 575°C. and about 700°C. in the presence of a catalyst comprising a crystalline aluminosilicate zeolite said zeolite having a silica to alumina ratio of at least about 12 and a constraint index within the approximate range of 1 to 12.
Claim 8
Dependent Claim
20 words
The process of claim 5 wherein said crystalline aluminosilicate zeolite is characterized by a silica/alumina ratio in excess of 30.
Claim 9
Dependent Claim
10 words
The process of claim 5 wherein said zeolite is ZSM-5.
Claim 10
Dependent Claim
16 words
The process of claim 5 wherein said methylating agent is methanol, methylchloride, methylbromide, dimethylether or dimethylsulfide.
Claim 11
Dependent Claim
23 words
The process of claim 5 wherein said reacting takes place at a weight hourly space velocity of between about 1 and about 2000.
Claim 12
Dependent Claim
15 words
The process of claim 5 wherein said crystalline aluminosilicate zeolite is in the hydrogen form.
Claim 13
Dependent Claim
18 words
The process of claim 5 wherein said crystalline aluminosilicate zeolite is used in combination with a porous matrix.
Claim 14
Dependent Claim
11 words
The process of claim 11 wherein said matrix is silica gel.
Claim 15
Dependent Claim
21 words
The process of claim 5 wherein the molar ratio of methylating agent to toluene is between about 0.05 and about 5.
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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) | 1979-06-22 | 1979-12-22 | 1980-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-22 | 1983-12-22 | 1984-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-22 | 1987-12-22 | 1988-06-22 | $7700.00 | Window Closed / Lapsed |