US4086289A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of xylenes
Assignee: Sunoco Inc R&M
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Filing: 1977-07-05
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Granted: 1978-04-25
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Expires: 1997-07-05
Abstract
Abstract In the process of methylating toluene to obtain a mixture of xylenes by contacting toluene with hydrogen and a carbon oxide-containing gas in the presence of a catalyst, the improvement of using as catalyst zinc chromite mixed with an alkali metal exchanged molecular sieve containing a stoichiometric excess of an alkali metal carbonate, whereby a more favorable proportion of p-xylene is obtained.
Inventors
- 👤 Walter H. Seitzer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:49
CPC Classifications
C; C07; C07C; C07C2/00; C07C2/86; C07C2/862; C07C2523/00; C07C2523/06; C07C2523/16; C07C2523/24; C07C2523/26; C07C2529/00; C07C2529/04; Y; Y10; Y10S; Y10S585/00; Y10S585/929; Y10S585/943
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
64 words
In the process of methylating toluene to obtain a mixture of xylenes relatively low in the meta-isomer and low in ethyl benzene content by contacting toluene with hydrogen and a carbon oxide-containing gas in the presence of a catalyst, the improvement of using as catalyst zinc chromite mixed with an alkali metal exchanged molecular sieve containing a stoichiometric excess of an alkali metal carbonate.
Claim 2
Dependent Claim
64 words
In the process of methylating toluene to obtain a mixture of xylenes relatively low in the meta-isomer and low in ethyl benzene content by contacting toluene with hydrogen and a carbon oxide-containing gas in the presence of a catalyst, the improvement of using as catalyst zinc chromite mixed with an alkali metal exchanged molecular sieve containing a stoichiometric excess of an alkali metal carbonate.
Claim 3
Dependent Claim
12 words
The process of claim 1 where the molecular sieve is a zeolite.
Claim 4
Dependent Claim
11 words
The process of claim 2 where the alkali metal is potassium.
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) | 1981-04-24 | 1981-10-24 | 1982-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-24 | 1985-10-24 | 1986-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-24 | 1989-10-24 | 1990-04-25 | $7700.00 | Window Closed / Lapsed |