US4307214A
Expired / Lapsed
US
⏱️ 0.0 years remaining
SC2 activation of supported chromium oxide catalysts
Assignee: Phillips Petroleum Co
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Filing: 1980-09-03
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Granted: 1981-12-22
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Expires: 2000-09-03
Abstract
Abstract A method for producing activated catalysts in which a catalyst containing chromium on a silica-containing support is (1) contacted with a gaseous environment consisting essentially of sulfur dioxide and oxygen at a temperature in a range of about 450° C. to about 1100° C. for a time ranging from about one to about five hours and (2) subsequently maintaining a temperature within the contact temperature range while contacting the catalyst with a gaseous environment consisting essentially of oxygen and gases inert to reaction with the catalyst. In another embodiment of the invention the temperature for a succeeding step is not raised above that attained in the previous step. In an embodiment of the invention the catalyst is contacted with a gaseous environment consisting essentially of oxygen and gases inert to reaction with the catalyst while the temperature is being increased prior to contact with sulfur dioxide.
Inventors
- 👤 Max P. McDaniel
- 👤 Melvin B. Welch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:34
CPC Classifications
C; C08; C08F; C08F10/00; C08F10/02
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
114 words
A method for producing polymers of ethylene comprising contacting ethylene or ethylene and comonomers chosen from the group consisting of aliphatic 1-olefins containing up to about 10 carbon atoms at polymerization conditions in the presence of a catalyst produced by the method comprising: (a) contacting a catalyst comprising chromium on a silica-containing support with a gaseous environment consisting essentially of sulfur dioxide and oxygen at a temperature within a temperature range and for a time sufficient to activate the catalyst and subsequently (b) maintaining a temperature within the contact temperature range of step (a) while contacting said catalyst with a gaseous environment consisting essentially of oxygen and gases inert to reaction with the catalyst.
Claim 2
Independent Claim
114 words
A method for producing polymers of ethylene comprising contacting ethylene or ethylene and comonomers chosen from the group consisting of aliphatic 1-olefins containing up to about 10 carbon atoms at polymerization conditions in the presence of a catalyst produced by the method comprising: (a) contacting a catalyst comprising chromium on a silica-containing support with a gaseous environment consisting essentially of sulfur dioxide and oxygen at a temperature within a temperature range and for a time sufficient to activate the catalyst and subsequently (b) maintaining a temperature within the contact temperature range of step (a) while contacting said catalyst with a gaseous environment consisting essentially of oxygen and gases inert to reaction with the catalyst.
Claim 3
Dependent Claim
38 words
A method of claim 1 wherein the catalyst is contacted with a gaseous environment consisting essentially of oxygen and gases inert to reaction with a catalyst while the temperature is being increased prior to contact with sulfur dioxide.
Claim 4
Dependent Claim
31 words
A method of claim 1 wherein the catalyst is contacted with a gaseous environment consisting essentially of sulfur dioxide and oxygen while the temperature is being increased to the activation range.
Claim 5
Dependent Claim
22 words
A method of claim 1, 2, or 3 wherein the temperature of step (b) is not raised above that of step (a).
Claim 6
Dependent Claim
24 words
A method of claim 1, 2, or 3 wherein the mole ratio of sulfur dioxide:oxygen is in the range of about 1:0.55 to 1:10.
Claim 7
Dependent Claim
78 words
A method of claim 1, 2 or 3, wherein said gaseous environment consisting essentially of sulfur dioxide and oxygen is at a temperature of about 450° to about 1100° C. (840° to 2000° F.), the contact time between the gaseous environment of sulfur dioxide and oxygen is in a range of about 1 to about 5 hours, and the total contact time between catalyst and gaseous environment is in the range of about 2 to about 20 hours.
Claim 8
Dependent Claim
35 words
A method of claim 6 wherein the contact between the catalyst and the gaseous environment of sulfur dioxide and oxygen is at a temperature range of about 540° C. to about 900° C. (1000°-1650° F.).
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-12-21 | 1985-06-22 | 1985-12-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-12-21 | 1989-06-22 | 1989-12-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-12-21 | 1993-06-22 | 1993-12-22 | $7700.00 | Window Closed / Lapsed |