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 13:14
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.
References Cited (Backward Citations)
US3156707A
Cited
US4035417A
Cited
US3915892A
Cited
US4017521A
Cited
US3864280A
Cited
US4187235A
Cited
US3987063A
Cited
US4002650A
Cited
US3932305A
Cited
US3931046A
Cited
US4043943A
Cited
US4064070A
Cited
US4016105A
Cited
US4149992A
Cited
US4147661A
Cited
US4179404A
Cited
US4244879A
Cited
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 |