US4370508A
Expired / Lapsed
US
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Para-selective zeolite catalysts treated with nitrogen compounds
Assignee: Mobil Oil AS
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Filing: 1981-06-26
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Granted: 1983-01-25
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Expires: 2001-06-26
Abstract
Abstract A process is provided for modifying ZSM-5 type zeolite catalysts with gaseous nitrogen-based treating agents in order to enhance the para-selective properties of such catalysts for the conversion of aromatic materials to dialkyl-substituted benzene compounds. Nitrogen-based treating agents include nitrogen dioxide and ammonia. Catalyst compositions so treated can be used in alkylation, transalkylation or disproportionation processes to provide product mixtures having exceptionally high concentrations of the para-dialkylbenzene isomer.
Inventors
- 👤 Warren W. Kaeding
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:23
CPC Classifications
C; C07; C07C; C07C6/00; C07C6/08; C07C6/12; C07C6/123; B; B01; B01J; B01J29/00; B01J29/04; B01J29/06; B01J29/40; C07C2/00; C07C2/54; C07C2/64; C07C2/66; C07C2/86; C07C2/861; C07C2/862; C07C2/864; C07C6/126; B01J2229/00; B01J2229/10; B01J2229/12; B01J2229/20; B01J2229/26; B01J2229/30; B01J2229/36; B01J2229/42; B01J29/65; B01J29/70; C07C2529/00; C07C2529/04; C07C2529/06; C07C2529/40; C07C2529/65; C07C2529/70
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
92 words
A process for converting aromatic compounds to a dialkyl benzene compound mixture highly enriched in the para-dialkylbenzene isomer, said process comprising contacting said aromatic compounds under conversion conditions with a modified zeolite based catalyst comprising a crystalline zeolite material characterized by a silica to alumina ratio of at least 12 and a constraint index of from about 1 to 12, said catalyst having been modified by treatment with a para-selectivity-enhancing oxide material and further having been contacted with a nitrogen-based treating agent selected from nitrogen dioxide and ammonia under para-selectivity enhancing conditions.
Claim 2
Dependent Claim
92 words
A process for converting aromatic compounds to a dialkyl benzene compound mixture highly enriched in the para-dialkylbenzene isomer, said process comprising contacting said aromatic compounds under conversion conditions with a modified zeolite based catalyst comprising a crystalline zeolite material characterized by a silica to alumina ratio of at least 12 and a constraint index of from about 1 to 12, said catalyst having been modified by treatment with a para-selectivity-enhancing oxide material and further having been contacted with a nitrogen-based treating agent selected from nitrogen dioxide and ammonia under para-selectivity enhancing conditions.
Claim 3
Dependent Claim
58 words
A process according to claim 1 wherein said para-selectivity enhancing conditions include contact of zeolite catalyst with treating agent at a temperature of from about 50° C. to 500° C. for a period of from about 0.1 to 25 hours, followed by calcination of the treated catalyst at a temperature of from about 300° C. to 600° C.
Claim 4
Dependent Claim
33 words
A process according to claim 2 wherein said zeolite catalyst contains from about 0.25% to 25% by weight of a modifying oxide selected from magnesium oxide, phosphorus oxide and mixtures of said oxides.
Claim 5
Dependent Claim
20 words
A process according to claim 3 wherein said zeolite is selected from ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38 and ZSM-48.
Claim 6
Dependent Claim
29 words
A process according to claim 3 wherein said nitrogen-based treating agent is provided in a treating medium comprising from about 25% to 100% by volume of said treating agent.
Claim 7
Dependent Claim
47 words
A process according to claim 5 wherein said treating medium is passed over said catalyst at the rate of from about 10 to 100 cc/min/gm catalyst at a temperature of from about 50° C. to 500° C. for a period of from about 0.25 to 2 hours.
Claim 8
Dependent Claim
18 words
A process according to claim 6 wherein said treating medium comprises 100% by volume of anhydrous nitrogen dioxide.
Claim 9
Dependent Claim
17 words
A process according to claim 6 wherein said treating medium comprises 100% by volume of anhydrous ammonia.
Claim 10
Dependent Claim
29 words
A process according to claim 1, 2, 3, 4, 5, 6, 7 or 8 which comprises alkylation of an aromatic compound with an alkylating agent to produce dialkylbenzene compounds.
Claim 11
Dependent Claim
33 words
A process according to claim 9 wherein said aromatic compound is toluene and said alkylating agent contains from 1 to about 16 carbon atoms and is selected from olefins, alkyl halides and alkanols.
Claim 12
Dependent Claim
24 words
A process according to claim 1, 2, 3, 4, 5, 6, 7 or 8 which comprises transalkylation of aromatic compounds to produce dialkylbenzene compounds.
Claim 13
Dependent Claim
25 words
A process according to claim 1, 2, 3, 4, 5, 6, 7 or 8 which comprises disproportionation of alkylbenzenes to produce benzenes and dialkylbenzene compounds.
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) | 1986-01-24 | 1986-07-26 | 1987-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-24 | 1990-07-26 | 1991-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-24 | 1994-07-26 | 1995-01-25 | $7700.00 | Window Closed / Lapsed |