Patent US3621072A successfully refreshed from Google Patents.
US3621072A
Expired / Lapsed
US
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Process for producing isoprene
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1968-12-12
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Granted: 1971-11-16
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Expires: 1988-12-12
Abstract
Abstract Isoprene is synthesized in high yield according to simple procedures and at low costs by passing a mixed gas comprising isobutylene, methanol and/or methyl ether, and oxygen gas, over a solid catalyst maintained at 100*-500* C. which contains as a component one member selected from the group consisting of oxides of vanadium, tungsten, molybdenum, uranium and the like, and mixtures thereof. When said catalyst is supported on a silica gel as a carrier, a high synergistic effect can be attained. If necessary, an acid, or an alkali or alkaline earth metal compound, may be used as a promotor.
Inventors
- 👤 Yoshihiro Watanabe
- 👤 Jiro Kobayashi
- 👤 Yoshiki Toyoshima
- 👤 Tooru Tokumaru
- 👤 Masatosi Saito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:50
CPC Classifications
C; C07; C07C; C07C2/00; C07C2/86; C07C2/862; C07C2/864; B; B01; B01J; B01J37/00; C07C2/865; C07C2521/00; C07C2521/06; C07C2521/08; C07C2523/00; C07C2523/12; C07C2523/16; C07C2523/20; C07C2523/22; C07C2523/24; C07C2523/26; C07C2523/28; C07C2523/30; C07C2523/70; C07C2523/72; C07C2523/74; C07C2523/75; C07C2527/00; C07C2527/02; C07C2527/14
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
21 words
A process according to claim 1 wherein the mixed gas is contacted with the solid catalyst in the presence of steam.
Claim 2
Dependent Claim
23 words
A process according to claim 1, wherein the mixed gas is contacted with the solid catalyst by use of a fluidized bed reactor.
Claim 3
Dependent Claim
33 words
A process according to claim 1 wherein the solid catalyst includes a promotor element selected from the group consisting of phosphorous, sulfur, boron, antimony, bismuth, tellurium, silver, barium, calcium, magnesium, potassium and sodium.
Claim 4
Dependent Claim
12 words
A compound according to claim 4 wherein said promoter element is phosphorous.
Claim 5
Dependent Claim
12 words
A compound according to claim 4 wherein said promoter element is sulfur.
Claim 6
Dependent Claim
16 words
A process according to claim 1 wherein said catalyst inclUdes a compound comprising silicon and oxygen.
Claim 7
Dependent Claim
25 words
A process according to claim 7 wherein said compound comprising silicon and oxygen is a solid having a surface area of up to 350 m.2/g.
Claim 8
Dependent Claim
12 words
A process according to claim 8 wherein said compound is silica gel.
Claim 9
Dependent Claim
89 words
A process for producing isoprene, which comprises contacting a gaseous mixture of isobutylene, oxygen and at least one compound selected from the group consisting of methanol and methyl ether at temperatures of 100*-500* C. with a solid catalyst comprising oxygen and at least one element selected from the group consisting of tungsten, vanadium, molybdenum, uranium, copper, iron and chromium, a promoter element element selected from the group consisting of phosphorous and sulfur and a solid compound of silicon and oxygen having a surface area of up to 350 m.2/g.
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) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |