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US2561483A
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Method for preparing isoprene by dehydration of 1-methoxy, 3-methyl, butene-3
Assignee: Produits Chimiques et Electrometallurgiques Alais Forges et Camargue
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Filing: 1949-06-01
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Granted: 1951-07-24
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Expires: 1969-06-01
Abstract
No abstract record available.
Inventors
- 👤 Seon Marius
- 👤 Raitzyn Isidor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:42
CPC Classifications
C; C07; C07C; C07C1/00; C07C1/20; C07C2521/00; C07C2521/02; C07C2521/04; C07C2521/12; C07C2527/00; C07C2527/02; C07C2527/053; C07C2527/14; C07C2527/16; C07C2527/167
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
66 words
METHOD OF PREPARING ISOPRENE WHICH COMPRISES PASSING 1-METHOXY, 3-METHYL, BUTENE-3 IN THE VAPOR PHASE OVER A DEHYDRATION CATALYST SELECTED FROM THE GROUP CONSISTING OF ALUMINA, ALUMINUM PHOSPHATE, ALUMINUM SILCATES, AND MIXTURES OF ALUMINUM SILICATES WITH METAL PHOSPHATES AND METAL SULPHATES, AT A TEMPERATURE WITHIN THE RANGE OF FROM ABOUT 220* C. TO ABOUT 430* C., CONDENSING THE REACTION PRODUCT AND SUBJECTING THE CONDENSATE TO FRACTIONAL DISTILLATION.
Claim 2
Dependent Claim
66 words
METHOD OF PREPARING ISOPRENE WHICH COMPRISES PASSING 1-METHOXY, 3-METHYL, BUTENE-3 IN THE VAPOR PHASE OVER A DEHYDRATION CATALYST SELECTED FROM THE GROUP CONSISTING OF ALUMINA, ALUMINUM PHOSPHATE, ALUMINUM SILCATES, AND MIXTURES OF ALUMINUM SILICATES WITH METAL PHOSPHATES AND METAL SULPHATES, AT A TEMPERATURE WITHIN THE RANGE OF FROM ABOUT 220* C. TO ABOUT 430* C., CONDENSING THE REACTION PRODUCT AND SUBJECTING THE CONDENSATE TO FRACTIONAL DISTILLATION.
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) | 1954-07-23 | 1955-01-22 | 1955-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-07-23 | 1959-01-22 | 1959-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-07-23 | 1963-01-22 | 1963-07-24 | $7700.00 | Window Closed / Lapsed |