US4521638A
Expired / Lapsed
US
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Process for preparation of tertiary olefins
Assignee: Mitsubishi Gas Chemical Co Inc
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Filing: 1984-02-16
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Granted: 1985-06-04
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Expires: 2004-02-16
Abstract
Abstract Disclosed is a process for the preparation of tertiary olefins which comprises catalytically decomposing a tertiary ether to a tertiary olefin, wherein the catalytic decomposition of the tertiary olefin is carried out in the presence of a solid phosphoric acid catalyst which has been calcined at a temperature of at least 500 DEG C. in an inert gas.
Inventors
- 👤 Koichi Kida
- 👤 Tetsuo Aoyama
- 👤 Takako Uchiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:07
CPC Classifications
B; B01; B01J; B01J27/00; B01J27/28; B01J27/14; B01J27/16; C; C07; C07C; C07C1/00; C07C1/20; C07C2521/00; C07C2521/02; C07C2521/04; C07C2521/06; C07C2521/12; C07C2521/16; C07C2523/00; C07C2523/12; C07C2527/00; C07C2527/14; C07C2527/16; C07C2527/167; C07C2527/173; C07C2529/00; C07C2529/04; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/584
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
68 words
In a process for the preparation of tertiary olefins which comprises catalytically decomposing a tertiary ether to a tertiary olefin, the improvement wherein the catalytic decomposition of the tertiary olefin is carried out in the presence of a solid phosphoric acid catalyst which has been calcined at a temperature not lower than 500° C. in an inert gas, said decomposition being carried out in the presence of steam.
Claim 2
Dependent Claim
68 words
In a process for the preparation of tertiary olefins which comprises catalytically decomposing a tertiary ether to a tertiary olefin, the improvement wherein the catalytic decomposition of the tertiary olefin is carried out in the presence of a solid phosphoric acid catalyst which has been calcined at a temperature not lower than 500° C. in an inert gas, said decomposition being carried out in the presence of steam.
Claim 3
Dependent Claim
68 words
A process for the preparation of tertiary olefins according to claim 1, wherein the tertiary ether is a compound represented by the following general formula: ##STR14## wherein R 1 , R 2 and R 3 , which may be the same or different, stand for an alkyl group having 1 to 4 carbon atoms, and R 4 stands for an alkyl group having 1 to 3 carbon atoms.
Claim 4
Dependent Claim
24 words
A process for the preparation of tertiary olefins according to claim 1, wherein the tertiary ether is methyl-t-butyl ether, methyl-t-amyl ether or ethyl-t-butyl ether.
Claim 5
Dependent Claim
33 words
A process for the preparation of tertiary olefins according to claim 1, wherein the phosphoric acid component of the solid phosphoric acid catalyst is orthophosphoric acid, pyrophosphoric acid, metaphosphoric acid or polyphosphoric acid.
Claim 6
Dependent Claim
23 words
A process for the preparation of tertiary olefins according to claim 1, wherein the solid phosphoric acid catalyst is derived from orthophosphoric acid.
Claim 7
Dependent Claim
28 words
A process for the preparation of tertiary olefins according to claim 1, wherein the carrier of the solid phosphoric acid catalyst is a carrier containing a metal oxide.
Claim 8
Dependent Claim
39 words
A process for the preparation of tertiary olefins according to claim 1, wherein the carrier of the solid phosphoric acid catalyst is diatomaceous earth, aluminum oxide, zirconium oxide, titanium oxide, thorium oxide, acid clay, activated clay, silica-aluminia or zeolite.
Claim 9
Dependent Claim
28 words
A process for the preparation of tertiary olefins according to claim 1, wherein the solid phosphoric acid catalyst contains nickel, copper, cobalt, iron, zinc, chromium, manganese or vanadium.
Claim 10
Dependent Claim
32 words
A process for the preparation of tertiary olefins according to claim 1, wherein the calcination of the solid phosphoric acid catalyst is carried out at a temperature of 500° to 1200° C.
Claim 11
Dependent Claim
53 words
A process for the preparation of tertiary olefins according to claim 1, wherein the solid phosphoric acid catalyst is one that has been dried and calcined at a low temperature of from room temperature to a temperature of lower than 500° C. and then calcined at a temperature of at least 500° C.
Claim 12
Dependent Claim
28 words
A process for the preparation of tertiary olefins according to claim 1, wherein the calcination of the solid phosphoric acid catalyst is conducted for 0.5 to 50 hours.
Claim 13
Dependent Claim
23 words
A process for the preparation of tertiary olefins according to claim 1, wherein the inert gas is air, nitrogen, helium, argon or steam.
Claim 14
Dependent Claim
51 words
A process for the preparation of tertiary olefins according to claim 1, wherein the solid phosphoric acid catalyst is one formed by supporting phosphoric acid on a support in an amount of 0.5 to 200 parts by weight as P 2 O 5 per 100 parts by weight of the carrier.
Claim 15
Dependent Claim
27 words
A process for the preparation of tertiary olefins according to claim 1, wherein the decomposition reaction temperature is in the range of from 100 to 400° C.
Claim 16
Dependent Claim
30 words
A process for the preparation of tertiary olefins according to claim 1, wherein the decomposition reaction pressure is in the range of from atmospheric pressure to 30 Kg/cm 2 .
Claim 17
Dependent Claim
36 words
A process for the preparation of tertiary olefins according to claim 1, wherein the weight hourly space velocity (WHSV) of the tertiary ether per unit volume of the catalyst is 0.3 to 100 g/ml of catalyst/hr.
Claim 18
Dependent Claim
34 words
A process for the preparation of tertiary olefins according to claim 1, wherein the molar ratio of steam (H 2 O) to the tertiary ether is in the range of from 0.05 to 30.
Claim 19
Dependent Claim
103 words
In a process for the preparation of tertiary olefins which comprises catalytically decomposing a tertiary ether to a tertiary olefin, the improvement wherein the catalytic decomposition of the tertiary ether to the tertiary olefin is carried out in the presence of a solid phosphoric acid catalyst which has been calcined at a temperature not lower than 500° C. in an inert gas, said decomposition being carried out in the presence of steam, and when the activity of the catalyst is lowered, the catalyst is regenerated by heating it at a temperature higher than the reaction temperature in the presence of an inert gas.
Claim 20
Dependent Claim
103 words
In a process for the preparation of tertiary olefins which comprises catalytically decomposing a tertiary ether to a tertiary olefin, the improvement wherein the catalytic decomposition of the tertiary ether to the tertiary olefin is carried out in the presence of a solid phosphoric acid catalyst which has been calcined at a temperature not lower than 500° C. in an inert gas, said decomposition being carried out in the presence of steam, and when the activity of the catalyst is lowered, the catalyst is regenerated by heating it at a temperature higher than the reaction temperature in the presence of an inert gas.
Claim 21
Dependent Claim
26 words
A process for the preparation of tertiary olefins according to claim 18, wherein the inert gas used for the regeneration is helium, nitrogen, steam or air.
Claim 22
Dependent Claim
33 words
A process for the preparation of tertiary olefins according to claim 18, wherein the regeneration temperature is higher by at least 50° C. than the decomposition reaction temperature but lower than 1100° C.
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) | 1988-06-03 | 1988-12-03 | 1989-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-03 | 1992-12-03 | 1993-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-03 | 1996-12-03 | 1997-06-04 | $7700.00 | Window Closed / Lapsed |