US2885409A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Maleic anhydride production and catalyst therefor
Assignee: Wyeth Holdings LLC
•
Filing: 1957-05-27
•
Granted: 1959-05-05
•
Expires: 1977-05-27
Abstract
No abstract record available.
Inventors
- 👤 Robert C Ryder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:46
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/38; B01J23/54; B01J23/66; B01J23/68; B01J23/683; B01J23/686; B01J23/16; B01J23/24; B01J23/28; C; C07; C07C; C07C51/00; C07C51/16; C07C51/31; C07C51/313
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
100 words
IN THE VAPOR PHASE CATALYTIC OXIDATION OF MONONUCLEAR AROMATIC COMPOUNDS TO MALETIC ANTHYDRIDE BY PASSING VAPORS THEREOF IN ADMIXTURE WITH AN OXYGENCONTAINING GAS THROUGH AND IN CONTACT WITH A FIXED-BED CATALYST THE IMPROVEMENT WHICH COMPRISES MAINTAINING A BED OF VANADIUM OXIDE-MOLYBEDENUM OXIDE CATALYST IN THE FORM OF AN ANNULUS OF FROM 1 TO 2 1/2 INCHES IN OUTSIDE DIAMETER AND A THICKNESS OF FROM 3/8 INCH TO ONE INCH SURROUNDED BY AND IN HEAT-EXCHANGING RELATION WITH A TEMPERATURE-REGULATING LIQUID MATINTAINED AT 380* -450* C. WHEREBY INCREASED CATALYST LOADINGS ARE OBTAINABLE WITHOUT LOSS OF MOLYBDENUM OXIDE FROM THE CATALYST BY VOLATILIZATION.
Claim 2
Dependent Claim
100 words
IN THE VAPOR PHASE CATALYTIC OXIDATION OF MONONUCLEAR AROMATIC COMPOUNDS TO MALETIC ANTHYDRIDE BY PASSING VAPORS THEREOF IN ADMIXTURE WITH AN OXYGENCONTAINING GAS THROUGH AND IN CONTACT WITH A FIXED-BED CATALYST THE IMPROVEMENT WHICH COMPRISES MAINTAINING A BED OF VANADIUM OXIDE-MOLYBEDENUM OXIDE CATALYST IN THE FORM OF AN ANNULUS OF FROM 1 TO 2 1/2 INCHES IN OUTSIDE DIAMETER AND A THICKNESS OF FROM 3/8 INCH TO ONE INCH SURROUNDED BY AND IN HEAT-EXCHANGING RELATION WITH A TEMPERATURE-REGULATING LIQUID MATINTAINED AT 380* -450* C. WHEREBY INCREASED CATALYST LOADINGS ARE OBTAINABLE WITHOUT LOSS OF MOLYBDENUM OXIDE FROM THE CATALYST BY VOLATILIZATION.
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) | 1962-05-04 | 1962-11-03 | 1963-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-05-04 | 1966-11-03 | 1967-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-05-04 | 1970-11-03 | 1971-05-05 | $7700.00 | Window Closed / Lapsed |