US3933932A
Expired / Lapsed
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Method of oxydehydrogenation of ethyl benzene
Assignee: Dow Chemical Co
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Filing: 1974-05-28
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Granted: 1976-01-20
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Expires: 1994-05-28
Abstract
Abstract Lanthanum phosphate, lanthanum pyrophosphate and rare earth phosphates and pyrophosphates containing a major portion of that lanthanum compound are good catalysts for oxydehydrogenating alkyl aromatic compounds, including nitrogen heterocyclics having 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°-640°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
2026-10-30 18:32
CPC Classifications
B; B01; B01J; B01J27/00; B01J27/14; B01J27/16; B01J27/18; B01J27/1802; B01J27/1804; C; C07; C07C; C07C5/00; C07C5/42; C07C5/48
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
96 words
A method of oxydehydrogenating ethyl benzene to styrene comprising feeding a mixture of from about 0.5 to about 4.0 moles of oxygen per mole of ethyl benzene, into admixture with a catalyst consisting essentially of lanthanum phosphate, lanthanum pyrophosphate, a rare earth phosphate having a predominant amount of lanthanum in the metal moiety or a rare earth pyrophosphate having a predominant amount of lanthanum in the metal moiety, at a reaction temperature of from about 450° to about 650°C., and a space velocity of from about 55 to about 2500 and recovering styrene from the effluent.
Claim 2
Independent Claim
96 words
A method of oxydehydrogenating ethyl benzene to styrene comprising feeding a mixture of from about 0.5 to about 4.0 moles of oxygen per mole of ethyl benzene, into admixture with a catalyst consisting essentially of lanthanum phosphate, lanthanum pyrophosphate, a rare earth phosphate having a predominant amount of lanthanum in the metal moiety or a rare earth pyrophosphate having a predominant amount of lanthanum in the metal moiety, at a reaction temperature of from about 450° to about 650°C., and a space velocity of from about 55 to about 2500 and recovering styrene from the effluent.
Claim 3
Dependent Claim
17 words
The method of claim 1 in which the reaction temperature is from about 500°C. to about 650°C.
Claim 4
Dependent Claim
24 words
The method of claim 1 in which the molar ratio of oxygen is from about 0.5 to 1.5 mols per mol of ethyl benzene.
Claim 5
Dependent Claim
23 words
The method of claim 3 in which molar ratio of oxygen is from about 0.9 to about 1.1 per mole of ethyl benzene.
Claim 6
Dependent Claim
42 words
The method of claim 1 in which the catalyst is lanthanum pyrophosphate, the feed contains 6.25 volumes of nitrogen and 1.04 volumes of oxygen per volume of vaporized ethyl benzene and the space velocity GSHV is about 240 hr. - 1 .
Claim 7
Dependent Claim
32 words
The method of claim 1 in which the catalyst is a rare earth pyrophosphate which has 65% lanthanum, about 27% neodymium and about 7% praseodymium, calculated as oxides, in the metal moiety.
Claim 8
Dependent Claim
12 words
The method of claim 1 in which the catalyst is lanthanum phosphate.
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) | 1979-01-19 | 1979-07-21 | 1980-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-19 | 1983-07-21 | 1984-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-19 | 1987-07-21 | 1988-01-20 | $7700.00 | Window Closed / Lapsed |