US4178464A
Expired / Lapsed
US
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Process for producing methacrylic acid
Assignee: Tosoh Corp
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Filing: 1978-07-14
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Granted: 1979-12-11
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Expires: 1998-07-14
Abstract
Abstract A process for producing methacrylic acid by the vapor phase catalytic oxidation of methacrolein with molecular oxygen or a molecular oxygen-containing gas comprises using a catalyst of multi-elemental complex oxide having the formula MoaPbAscVdCueCefCrgOh wherein a, b, c, d, e, f, g and h respectively represent atomic ratios and a=12, b=0.5 to 3.0, c=0.01 to 1.2, d=0.01 to 2.0, e=0.01 to 2.0, f=0.01 to 1.2, g=0 to 2.0; and h is decided on the valences of the other components such as usually 37 to 60 which is prepared with or without a reduction using a dibasic carboxylic acid, an oxycarboxylic acid, mannitol or pyrogallol.
Inventors
- 👤 Teruhisa Sakamoto
- 👤 Shigeo Nakamura
- 👤 Nobuyuki Taniguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:37
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/70; B01J23/76; B01J23/84; B01J23/85; B01J23/88; B01J23/887; B01J23/8871; B01J23/8874; B01J23/8878; B01J27/00; B01J27/14; B01J27/186; B01J27/195; B01J27/198
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
93 words
A process for producing methacrylic acid by the vapor phase catalytic oxidation of methacrolein with molecular oxygen or a molecular oxygen-containing gas, which comprises: conducting said oxidation reaction over a catalyst consisting of a multi-element complex oxide having the formula: Mo.sub.a P.sub.b As.sub.c V.sub.d Cu.sub.e Ce.sub.f Cr.sub.g O.sub.h wherein a=12, b=0.5 to 3.0, c=0.01 to 1.2, d=0.01 to 2.0, e=0.01 to 2.0, f=0.01 to 1.2, g=0 to 2.0 and h assumes a value which is dependent upon the valences of the other components of the catalyst within the range of 37 to 60.
Claim 2
Dependent Claim
93 words
A process for producing methacrylic acid by the vapor phase catalytic oxidation of methacrolein with molecular oxygen or a molecular oxygen-containing gas, which comprises: conducting said oxidation reaction over a catalyst consisting of a multi-element complex oxide having the formula: Mo.sub.a P.sub.b As.sub.c V.sub.d Cu.sub.e Ce.sub.f Cr.sub.g O.sub.h wherein a=12, b=0.5 to 3.0, c=0.01 to 1.2, d=0.01 to 2.0, e=0.01 to 2.0, f=0.01 to 1.2, g=0 to 2.0 and h assumes a value which is dependent upon the valences of the other components of the catalyst within the range of 37 to 60.
Claim 3
Dependent Claim
21 words
The process of claim 1, wherein said catalyst is reduced with a dibasic carboxylic acid, an oxycarboxylic acid, mannitol or pyrogallol.
Claim 4
Dependent Claim
93 words
A process for producing methacrylic acid by the vapor phase catalytic oxidation of methacrolein with molecular oxygen or a molecular oxygen-containing gas, which comprises: conducting said oxidation reaction over a catalyst consisting of a multi-element complex oxide having the formula: Mo.sub.a P.sub.b As.sub.c V.sub.d Cu.sub.e Ce.sub.f Cr.sub.g O.sub.h wherein a=12, b=1.2 to 2.4, c=0.06 to 0.8, d=0.1 to 1.0, e=0.1 to 0.8, f=0.1 to 0.6, g=0 to 0.8 and h assumes a value which is dependent upon the valences of the other components of the catalyst within the range of 40 to 52.
Claim 5
Dependent Claim
93 words
A process for producing methacrylic acid by the vapor phase catalytic oxidation of methacrolein with molecular oxygen or a molecular oxygen-containing gas, which comprises: conducting said oxidation reaction over a catalyst consisting of a multi-element complex oxide having the formula: Mo.sub.a P.sub.b As.sub.c V.sub.d Cu.sub.e Ce.sub.f Cr.sub.g O.sub.h wherein a=12, b=1.2 to 2.4, c=0.06 to 0.8, d=0.1 to 1.0, e=0.1 to 0.8, f=0.1 to 0.6, g=0 to 0.8 and h assumes a value which is dependent upon the valences of the other components of the catalyst within the range of 40 to 52.
Claim 6
Dependent Claim
21 words
The process of claim 3, wherein said catalyst is reduced with a dibasic carboxylic acid, an oxycarboxylic acid, mannitol or pyrogallol.
Claim 7
Dependent Claim
19 words
The process of claim 3, wherein said oxidation reaction is conducted at a temperature of 280° to 300° C.
Claim 8
Dependent Claim
36 words
A process according to claim 2 or 4 wherein the amount of the dibasic carboxylic acid, oxycarboxylic acid, mannitol and pyrogallol to the multi-element complex oxide is in a range of 5 to 40 wt. %.
Claim 9
Dependent Claim
26 words
The process of claim 6, wherein said dibasic carboxylic acid is oxalic acid or succinic acid and said oxycarboxylic acid is citric acid or tartaric acid.
Claim 10
Dependent Claim
20 words
The process of claim 6, wherein the amount of said reducing agent employed ranges from 10 to 20 wt. %.
References Cited (Backward Citations)
US4035417A
Cited
US3875220A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-12-10 | 1983-06-11 | 1983-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-12-10 | 1987-06-11 | 1987-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-12-10 | 1991-06-11 | 1991-12-11 | $7700.00 | Window Closed / Lapsed |