US4378306A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surface heat treatment of silica-containing catalyst base
Assignee: Phillips Petroleum Co
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Filing: 1981-09-17
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Granted: 1983-03-29
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Expires: 2001-09-17
Abstract
Abstract A silica base for a chromium olefin polymerization catalyst is subjected to a high temperature treatment as for instance by passing the silica through a flame in order to alter the surface characteristics. The chromium can be present during the flame treatment or added later. The result is a catalyst capable of giving a broader molecular weight distribution polymer which is of particular value with the silica-titania coprecipitated catalyst used in slurry olefin polymerization.
Inventors
- 👤 Max P. McDaniel
- 👤 M. Bruce Welch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:10
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/16; B01J23/24; B01J23/26; B01J21/00; B01J21/06; B01J21/063; C; C08; C08F; C08F10/00; C08F10/02
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
57 words
A method comprising: subjecting a particulate silica-containing material to a heat treatment for a time and at a temperature sufficient to sinter the outside of the particles of said silica-containing material without significantly affecting the inside of the particles, said silica-containing material either having chromium contained therein during said heat treatment or having chromium thereafter added thereto.
Claim 2
Independent Claim
57 words
A method comprising: subjecting a particulate silica-containing material to a heat treatment for a time and at a temperature sufficient to sinter the outside of the particles of said silica-containing material without significantly affecting the inside of the particles, said silica-containing material either having chromium contained therein during said heat treatment or having chromium thereafter added thereto.
Claim 3
Dependent Claim
24 words
A method according to claim 1 wherein said thus heat treated silica-containing material containing said chomium is activated by heating in an oxygen-containing ambient.
Claim 4
Dependent Claim
33 words
A method according to claim 2 wherein said heat treatment is effected by passing said silica-containing material already containing said chromium through a flame, and wherein said silica-containing material is a silica-titania cogel.
Claim 5
Independent Claim
49 words
A method comprising: passing a particulate silica-containing material through a zone at a temperature within the range of 1200° to 4000° C. for a residence time within the range of 0.1 to 3 seconds, said silica-containing material either containing chromium during said passing or having chromium thereafter added thereto.
Claim 6
Independent Claim
49 words
A method comprising: passing a particulate silica-containing material through a zone at a temperature within the range of 1200° to 4000° C. for a residence time within the range of 0.1 to 3 seconds, said silica-containing material either containing chromium during said passing or having chromium thereafter added thereto.
Claim 7
Dependent Claim
46 words
A method according to claim 4 wherein the thus heat treated silica-containing material containing said chromium is activated by heating in an oxygen-containing ambient at a temperature within the range of 600° to 800° C. for a time within the range of 0.5 to 24 hours.
Claim 8
Dependent Claim
14 words
A method according to claim 4 wherein said silica-containing material is a silica-titania-chromium tergel.
Claim 9
Dependent Claim
21 words
A method according to claim 4 wherein said silica-containing material is a silica-titania cogel containing 1 to 12 weight percent titanium.
Claim 10
Dependent Claim
14 words
A method according to claim 7 wherein said chromium is present during said passing.
Claim 11
Dependent Claim
80 words
A method according to claim 8 wherein said chromium is introduced by combining an aqueous solution of a chromium compound selected from CrO 3 , chromium acetate and chromium nitrate with said cogel at a hydrogel stage thereof and said cogel is formed by adding sodium silicate to sulfuric acid containing a titanium compound, aging, washing with water to remove sodium ions and removing water by contact with one of ethyl acetate, or a 5 or 6 carbon atom alcohol.
Claim 12
Dependent Claim
26 words
A method according to claim 9 wherein said zone of 1200° to 4000° C. is a flame and said time range is 0.5 to 2 seconds.
Claim 13
Dependent Claim
9 words
A catalyst produced by the method of claim 10.
Claim 14
Dependent Claim
9 words
A catalyst produced by the method of claim 4.
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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) | 1986-03-28 | 1986-09-27 | 1987-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-28 | 1990-09-27 | 1991-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-28 | 1994-09-27 | 1995-03-29 | $7700.00 | Window Closed / Lapsed |