US3856927A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acceleration of oxidation processes over vanadia catalysts
Assignee: Individual
•
Filing: 1972-07-12
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Granted: 1974-12-24
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Expires: 1992-07-12
Abstract
Abstract A gaseous mixture comprising an oxidizable substance and oxygen is passed over a vanadia catalyst while one or more of these reaction conditions is cycled: A. RATIO OF OXIDIZABLE SUBSTANCE TO OXYGEN, B. SUM OF THE PARTIAL PRESSURES OF OXIDIZABLE SUBSTANCE AND OXYGEN, C. THE FLOW RATE OF THE GASEOUS MIXTURE, D. THE TEMPERATURE AT WHICH THE GASEOUS MIXTURE IS PASSED TO THE CATALYST, AND E. THE TEMPERATURE OF THE CATALYST ITSELF; THE CYCLES ARE OF ABOUT TWO TO ABOUT EIGHT HOURS DURATION. Under these conditions the rate of reaction is significantly greater than the rate under steady-state conditions normally used.
Inventors
- 👤 P Silveston
- 👤 R Hudgins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 23:55
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/16; C07C51/31; C07C51/313; C01; C01B; C01B17/00; C01B17/69; C01B17/74; C01B17/76; C07C51/21; C07C51/255; C07C51/265
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
93 words
IN A PROCESS FOR PRODUCING SULFUR TRIOXIDE WHICH COMPRISES PASSING A GASEOUS REACTION MIXTURE COMPRISING OXYGEN AND SULFUR DIOXIDE OVER VANADIUM PENTOXIDE CATALYST, THE IMPROVEMENT WHICH COMPRISES: CARRYING OUT THE REACTION WHILE THE RATIO OF PARTIAL PRESSURE OF SULFUR DIOXIDE TO OXYGEN IS VARIED IN CYCLES FROM A VALUE SELECTED FROM THE RANGE OF ABOUT 0.6 TO ABOUT 1.1 AND THE POSITIVE AND NEGATIVE VARIATIONS FROM SAID VALUE ARE WITHIN THE RANGE FROM ABOUT 0.2 TO ABOUT 0.5 AND ARE OF EQUAL MAGNITUDE, SAID CYCLES BEING OF ABOUT 2 TO 8 HOURS DURATION.
Claim 2
Dependent Claim
93 words
IN A PROCESS FOR PRODUCING SULFUR TRIOXIDE WHICH COMPRISES PASSING A GASEOUS REACTION MIXTURE COMPRISING OXYGEN AND SULFUR DIOXIDE OVER VANADIUM PENTOXIDE CATALYST, THE IMPROVEMENT WHICH COMPRISES: CARRYING OUT THE REACTION WHILE THE RATIO OF PARTIAL PRESSURE OF SULFUR DIOXIDE TO OXYGEN IS VARIED IN CYCLES FROM A VALUE SELECTED FROM THE RANGE OF ABOUT 0.6 TO ABOUT 1.1 AND THE POSITIVE AND NEGATIVE VARIATIONS FROM SAID VALUE ARE WITHIN THE RANGE FROM ABOUT 0.2 TO ABOUT 0.5 AND ARE OF EQUAL MAGNITUDE, SAID CYCLES BEING OF ABOUT 2 TO 8 HOURS DURATION.
Claim 3
Dependent Claim
17 words
The improvement of claim 1, wherein the said cycles are of about 4 to 6 hours duration.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |