Patent EP0309318A1 successfully refreshed from Google Patents.
Patent US4293498A successfully refreshed from Google Patents.
US4293498A
Expired / Lapsed
US
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Preparation of maleic anhydride
Assignee: Standard Oil Co
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Filing: 1980-10-22
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Granted: 1981-10-06
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Expires: 2000-10-22
Abstract
Abstract The present invention provides a process for the preparation of oxidation catalysts containing mixed oxides of vanadium and phosphorus, which catalysts are particularly effective in the oxidation of n-butane, n-butenes, 1,3-butadiene or a mixture thereof with molecular oxygen or an oxygen-containing gas in the vapor phase to produce high yields of maleic anhydride with good selectivity. A vanadium compound is introduced into an olefinic halogenated organic liquid medium, a phosphorus-containing compound is added to the medium, reduction of at least a portion of the vanadium to a +4 valence state is effected either prior to or subsequent to the addition of the phosphorus-containing compound, and the resulting vanadium-phosphorus oxide catalyst precursor is recovered, dried and calcined.
Inventors
- 👤 Michael F. Lemanski
- 👤 Noel J. Bremer
- 👤 Ernest C. Milberger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:33
CPC Classifications
C; C07; C07D; C07D307/00; C07D307/02; C07D307/34; C07D307/56; C07D307/60; C07C; C07C51/00; C07C51/16; C07C51/21; C07C51/25; C07C51/252; B; B01; B01J; B01J23/00; B01J23/002; B01J27/00; B01J27/14; B01J27/186; B01J27/195; B01J27/198; C07C51/215; B01J2523/00
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
123 words
A process for the production of maleic anhydride by the oxidation of n-butane, n-butene, 1,3-butadiene or a mixture thereof with molecular oxygen or oxygen-containing gas in the vapor phase at a reaction temperature of 250° C.-600° C. in the presence of a catalyst containing the mixed oxides of vanadium and phosphorus, wherein said catalyst is prepared by (a) introducing a pentavalent vanadium-containing compound into an olefinic, halogenated organic liquid-containing liquid medium, (b) effecting reduction of at least a portion of said vanadium to a valence state of about +4; (c) adding a phosphorus-containing compound to said medium before or after effecting said reduction to form a catalyst precursor; (d) recovering the catalyst precursor; (e) drying the catalyst precursor; (f) calcining the catalyst precursor.
Claim 2
Dependent Claim
123 words
A process for the production of maleic anhydride by the oxidation of n-butane, n-butene, 1,3-butadiene or a mixture thereof with molecular oxygen or oxygen-containing gas in the vapor phase at a reaction temperature of 250° C.-600° C. in the presence of a catalyst containing the mixed oxides of vanadium and phosphorus, wherein said catalyst is prepared by (a) introducing a pentavalent vanadium-containing compound into an olefinic, halogenated organic liquid-containing liquid medium, (b) effecting reduction of at least a portion of said vanadium to a valence state of about +4; (c) adding a phosphorus-containing compound to said medium before or after effecting said reduction to form a catalyst precursor; (d) recovering the catalyst precursor; (e) drying the catalyst precursor; (f) calcining the catalyst precursor.
Claim 3
Dependent Claim
111 words
A process for the production of maleic anhydride by the oxidation of n-butane, n-butene, 1,3 butadiene or a mixture thereof with molecular oxygen or oxygen-containing gas in the vapor phase at a reaction temperature of 250° C.-600° C. in the presence of a catalyst containing the mixed oxides of vanadium and phosphorus prepared from at least one pentavalent vanadium-containing compound and at least one phosphorus-containing compound wherein the pentavalent vanadium is reduced an average valence state of about +3.5 to about +4.6, including the step of effecting reduction of at least a portion of the pentavalent vanadium to a valence state of +4 in an olefinic, halogenated organic liquid-containing liquid medium.
Claim 4
Dependent Claim
111 words
A process for the production of maleic anhydride by the oxidation of n-butane, n-butene, 1,3 butadiene or a mixture thereof with molecular oxygen or oxygen-containing gas in the vapor phase at a reaction temperature of 250° C.-600° C. in the presence of a catalyst containing the mixed oxides of vanadium and phosphorus prepared from at least one pentavalent vanadium-containing compound and at least one phosphorus-containing compound wherein the pentavalent vanadium is reduced an average valence state of about +3.5 to about +4.6, including the step of effecting reduction of at least a portion of the pentavalent vanadium to a valence state of +4 in an olefinic, halogenated organic liquid-containing liquid medium.
Claim 5
Dependent Claim
21 words
The process of claims 1 or 2 wherein said reduction of vanadium is effected in the presence of the phosphorus-containing compound.
Claim 6
Dependent Claim
17 words
A process as recited in claims 1 or 2 wherein said organic liquid medium is essentially anhydrous.
Claim 7
Dependent Claim
22 words
A process as recited in claims 1 or 2 wherein reduction of said vanadium is effected by heating the vanadium-containing liquid medium.
Claim 8
Dependent Claim
19 words
A process as recited in claims 1 or 2 wherein said organic liquid contains a chlorinated olefinic organic liquid.
Claim 9
Dependent Claim
19 words
A process as recited in claims 1 or 2 wherein said organic liquid contains a brominated olefinic organic liquid.
Claim 10
Dependent Claim
25 words
A process as recited in claims 1 or 2 wherein said olefinic, halogenated organic liquid is selected from hexachlorobutadiene, perchloropropene, hexachlorocyclopentadiene, tetrabromoethylene and mixtures thereof.
Claim 11
Dependent Claim
62 words
A process as recited in claims 1 or 2 wherein said oxidation catalyst is represented by the empirical formula V.sub.1 P.sub.a M.sub.b O.sub.x wherein M is selected from U, Co, Mo, Fe, Zn, Hf, Zr and mixtures thereof; wherein a=0.5 to 2.0, b=0 to 1.0 and x is the number of oxygens required to satisfy the valence requirements of the other elements.
Claim 12
Dependent Claim
22 words
A process as recited in claims 1 or 2 wherein said organic liquid has a boiling point greater than about 150° C.
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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) | 1984-10-05 | 1985-04-06 | 1985-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-05 | 1989-04-06 | 1989-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-05 | 1993-04-06 | 1993-10-06 | $7700.00 | Window Closed / Lapsed |