US3957897A
Expired / Lapsed
US
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Method of oxydehydrogenation of alkyl aromatic compounds
Assignee: Dow Chemical Co
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Filing: 1974-05-28
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Granted: 1976-05-18
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Expires: 1994-05-28
Abstract
Abstract Certain alkaline earth pyrophosphates, such as Ca, Mg, and Sr pyrophosphates are superior catalysts for oxydehydrogenating alkyl aromatic compounds including nitrogen heterocyclics which have at least one C 2 -C 6 alkyl side chain to form derivatives having side chain unsaturation. The alkyl aromatic compound can have 1-2 rings. The process is carried out at 450°-650°C. and a space velocity of 55-2500.
Inventors
- 👤 G. Edwin Vrieland
- 👤 Hans R. Friedli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:28
CPC Classifications
C; C07; C07C; C07C5/00; C07C5/42; C07C5/48; B; B01; B01J; B01J27/00; B01J27/14; B01J27/16; B01J27/18; B01J27/1802; B01J27/1806; C07C17/00; C07C17/35; C07C17/357; C07C37/00; C07C37/001
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
96 words
A method of dehydrogenating an alkyl aromatic compound, selected from the class consisting of ethyl benzene, ethyl toluene, t-butyl ethyl benzene, diethyl benzene, ring chlorinated or brominated ethyl benzene, ethyl naphthalene, ethyl phenol, and isopropyl benzene to form a derivative having aliphatic unsaturation in the side chain, comprising passing a mixture of said alkyl aromatic compound and an oxygen containing gas in a mole ratio of 0.5 to 4.0 moles oxygen per mole of alkyl aromatic compound, over at least one of calcium, magnesium or strontium pyrophosphate, at a temperature from about 450° to about 650°C.
Claim 2
Independent Claim
96 words
A method of dehydrogenating an alkyl aromatic compound, selected from the class consisting of ethyl benzene, ethyl toluene, t-butyl ethyl benzene, diethyl benzene, ring chlorinated or brominated ethyl benzene, ethyl naphthalene, ethyl phenol, and isopropyl benzene to form a derivative having aliphatic unsaturation in the side chain, comprising passing a mixture of said alkyl aromatic compound and an oxygen containing gas in a mole ratio of 0.5 to 4.0 moles oxygen per mole of alkyl aromatic compound, over at least one of calcium, magnesium or strontium pyrophosphate, at a temperature from about 450° to about 650°C.
Claim 3
Dependent Claim
12 words
The method of claim 1 in which the catalyst is calcium pyrophosphate.
Claim 4
Dependent Claim
12 words
The method of claim 1 in which the catalyst is magnesium pyrophosphate.
Claim 5
Dependent Claim
11 words
The method claim 1 in which the catalyst is strontium pyrophosphate.
Claim 6
Dependent Claim
34 words
The method of claim 2 in which a mixture of an inert diluent, oxygen and ethyl benzene in a mole ratio of 6:1:1, respectively, is passed over β-calcium pyrophosphate at a temperature of 525°-530°C.
Claim 7
Dependent Claim
35 words
The method of claim 2 in which a mixture of an inert diluent, oxygen and ethyl benzene in a mole ratio of 6:1:1, respectively, is passed over the magnesium pyrophosphate at a temperature of 527°-532°C.
Claim 8
Dependent Claim
28 words
The method of claim 1 in which a mixture of an inert diluent, oxygen and ethyl benzene is passed over strontium pyrophosphate catalyst at a temperature of 527°-532°C.
Claim 9
Dependent Claim
16 words
The method of claim 1 in which the temperature is from about 500° to about 650°C.
Claim 10
Dependent Claim
17 words
The method of claim 1 in which the space velocity is from about 250 to about 1800.
Claim 11
Dependent Claim
17 words
The method of claim 9 in which the space velocity is from about 800 to about 1800.
Claim 12
Dependent Claim
14 words
The method of claim 2 in which the alkyl aromatic compound is ethyl benzene.
Claim 13
Dependent Claim
14 words
The method of claim 3 in which the alkyl aromatic compound is ethyl benzene.
Claim 14
Dependent Claim
14 words
The method of claim 4 in which the alkyl aromatic compound is ethyl benzene.
Claim 15
Dependent Claim
14 words
The method of claim 1 in which the alkyl aromatic compound is ethyl naphthalene.
References Cited (Backward Citations)
US3149082A
Cited
US3409696A
Cited
US3451945A
Cited
US3541172A
Cited
US3781222A
Cited
US3733327A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-05-18 | 1979-11-17 | 1980-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-18 | 1983-11-17 | 1984-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-18 | 1987-11-17 | 1988-05-18 | $7700.00 | Window Closed / Lapsed |