US3923916A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oxydehydrogenation of ethyl benzene
Assignee: Dow Chemical Co
•
Filing: 1974-05-28
•
Granted: 1975-12-02
•
Expires: 1994-05-28
Abstract
Abstract Nickel pyrophosphate is a superior catalyst for oxydehydrogenating alkyl aromatic compounds including heterocyclics which have at least one C2-C6 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- 2,500.
Inventors
- 👤 G Edwin Vrieland
- 👤 Hans R Friedli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:58
CPC Classifications
C; C07; C07C; C07C5/00; C07C5/42; C07C5/48
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
66 words
A METHOD OF DEHYDROGENATING ETHYL BENZENE TO FORM STYRENE COMPRISING PASSING AN OXYGEN CONTAINING GAS AND VAPORS OF SAID ETHYL BENZENE IN A MOLE RATIO OF FROM ABOUT 0.5 TO ABOUT 4 MOLES OF OXYGEN PER MOLE OF ETHYL BENZENE OVER A NICKEL PYROPHOSPHATE CATALYST AT A TEMPERATURE OF FROM ABOUT 450* TO ABOUT 650*C. AT A SPACE VELOCITY OF FROM ABOUT 55 TO BOUT 2500.
Claim 2
Independent Claim
66 words
A METHOD OF DEHYDROGENATING ETHYL BENZENE TO FORM STYRENE COMPRISING PASSING AN OXYGEN CONTAINING GAS AND VAPORS OF SAID ETHYL BENZENE IN A MOLE RATIO OF FROM ABOUT 0.5 TO ABOUT 4 MOLES OF OXYGEN PER MOLE OF ETHYL BENZENE OVER A NICKEL PYROPHOSPHATE CATALYST AT A TEMPERATURE OF FROM ABOUT 450* TO ABOUT 650*C. AT A SPACE VELOCITY OF FROM ABOUT 55 TO BOUT 2500.
Claim 3
Dependent Claim
36 words
The method of claim 1 in which the temperature is 500*C. to 650*C. and a reaction mixture is fed at a ratio of about 0.5 to about 4.0 moles of oxygen per mole of ethyl benzene.
Claim 4
Dependent Claim
38 words
The method of claim 2 in which the temperature is 533*C., and a reaction mixture is fed at a ratio of 15 cc of O2 and 90 cc of helium for each 15 cc of vaporIzed ethyl benzene.
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) | 1978-12-01 | 1979-06-02 | 1979-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-01 | 1983-06-02 | 1983-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-01 | 1987-06-02 | 1987-12-02 | $7700.00 | Window Closed / Lapsed |