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US4228261A
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Supported chromium-oxide polymerization catalyst having a porous silica support used in the polymerization of olefines
Assignee: Stamicarbon BV
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Filing: 1979-04-23
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Granted: 1980-10-14
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Expires: 1999-04-23
Abstract
Abstract Process for the preparation of a porous, pure silica which is particularly suitable as a catalyst support for a chromium-oxide catalyst used in polymerizing of olefins. The process comprises the steps of converting a silicon-halogen compound to a silica and then admixing with water to form a silica gel. The gel is then dried and ground to a predetermined particle size. The silica can then be made into a catalyst by placing on the support a chromium compound and then heating in a non-reducing atmosphere.
Inventors
- 👤 Joseph J. F. Scholten
- 👤 Lambertus J. M. A. VAN DE Leemput
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:41
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/16; B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/103; C08; C08F; C08F10/00; Y; Y10; Y10S; Y10S526/00; Y10S526/906; Y10S526/908
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
163 words
In a process for polymerizing olefines, the improvement consisting of using as the polymerization catalyst, a supported chromium-oxide catalyst having as the support a porous, pure silica with a pore volume of at least about 1.0 cm 3 /gram and a sodium content of at most about 200 ppm prepared by the process comprising the steps of (a) admixing to a non-porous silica prepared by the flame hydrolysis of a silicon-halogen compound at least about 50% by weight of water per weight of water plus silica, (b) forming a silica gel from said admixture of non-porous silica and water, (c) heating said gel at a temperature between about 200° C. to about 1000° C. to dry the gel, (d) grinding the dried silica to a particle size of at least about 10 microns to form a catalyst support, (e) placing a chromium compound on said support, and (f) heating the supported chromium compound in a non-reducing atmosphere to form a supported chromium-oxide catalyst.
Claim 2
Dependent Claim
163 words
In a process for polymerizing olefines, the improvement consisting of using as the polymerization catalyst, a supported chromium-oxide catalyst having as the support a porous, pure silica with a pore volume of at least about 1.0 cm 3 /gram and a sodium content of at most about 200 ppm prepared by the process comprising the steps of (a) admixing to a non-porous silica prepared by the flame hydrolysis of a silicon-halogen compound at least about 50% by weight of water per weight of water plus silica, (b) forming a silica gel from said admixture of non-porous silica and water, (c) heating said gel at a temperature between about 200° C. to about 1000° C. to dry the gel, (d) grinding the dried silica to a particle size of at least about 10 microns to form a catalyst support, (e) placing a chromium compound on said support, and (f) heating the supported chromium compound in a non-reducing atmosphere to form a supported chromium-oxide catalyst.
Claim 3
Dependent Claim
11 words
Process of claim 1, wherein the olefin being polymerized is ethylene.
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) | 1983-10-14 | 1984-04-14 | 1984-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-14 | 1988-04-14 | 1988-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-14 | 1992-04-14 | 1992-10-14 | $7700.00 | Window Closed / Lapsed |