Patent US4225464A successfully refreshed from Google Patents.
US4225464A
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Process of preparing a porous, pure silica
Assignee: Stamicarbon BV
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Filing: 1978-07-14
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Granted: 1980-09-30
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Expires: 1998-07-14
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 spray-dried to achieve the required particle size and pore volume. 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
2026-11-04 10:55
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/16; B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/103; B01J23/00; B01J23/16; B01J23/24; B01J23/26; C08; C08F; C08F10/00; Y; Y10; Y10S; Y10S526/00; Y10S526/906; Y10S526/908
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
92 words
Process for preparing a porous, pure silica with a sodium content of at most about 200 ppm, a pore volume of at least about 1.0 cm 3 /g and an average particle size of at least about 10 microns, comprising the steps of (a) admixing to a non-porous silica prepared by the flame hydrolysis of a silica-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, and (c) spray drying said silica gel.
Claim 2
Dependent Claim
92 words
Process for preparing a porous, pure silica with a sodium content of at most about 200 ppm, a pore volume of at least about 1.0 cm 3 /g and an average particle size of at least about 10 microns, comprising the steps of (a) admixing to a non-porous silica prepared by the flame hydrolysis of a silica-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, and (c) spray drying said silica gel.
Claim 3
Dependent Claim
25 words
Process of claim 1, wherein the spray-drying is carried out to obtain a silica gel with an average particle size of at least about 40μ.
Claim 4
Dependent Claim
23 words
Process of claim 1, wherein the spray-drying is carried out to obtain a silica gel with an average particle size of about 80μ.
Claim 5
Dependent Claim
25 words
Process of claim 1, wherein the spray-drying is carried out to obtain a silica gel with an average particle size of at most about 250μ.
Claim 6
Dependent Claim
28 words
Process of claim 1, 2, 3 or 4, wherein the silica of step (a) is admixed with a triple to tenfold amount of water to silica by weight.
Claim 7
Dependent Claim
20 words
Process of claim 5, wherein ammonia, sodium hydroxide or another base is added to step (b) as an agglomeration agent.
Claim 8
Dependent Claim
12 words
Process of claim 6, wherein ammonia is added as the agglomeration agent.
Claim 9
Dependent Claim
112 words
Process for preparing a supported chromium-oxide catalyst having as the support, a porous, pure silica with a sodium content of at most about 200,ppm and a pore volume of at least about 1.0 cm 3 /g comprising the steps of (a) admixing to a non-porous silica prepared by the flame hydrolysis of a silica-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) spray drying said silica gel to form a catalyst support, (d) placing a chromium compound on said support, and (e) heating the supported chromium compound in a non-reducing atmosphere.
Claim 10
Dependent Claim
112 words
Process for preparing a supported chromium-oxide catalyst having as the support, a porous, pure silica with a sodium content of at most about 200,ppm and a pore volume of at least about 1.0 cm 3 /g comprising the steps of (a) admixing to a non-porous silica prepared by the flame hydrolysis of a silica-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) spray drying said silica gel to form a catalyst support, (d) placing a chromium compound on said support, and (e) heating the supported chromium compound in a non-reducing atmosphere.
Claim 11
Dependent Claim
120 words
The supported chromium-oxide catalyst having as the support a porous, pure silica with a sodium content of at most about 200 ppm and a pore volume of at least about 1.0 cm 3 /g prepared by the process comprising the steps of (a) admixing to a non-porous silica prepared by the flame hydrolysis of a silica-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) spray drying said silica gel to form a catalyst support, (d) placing a chromium compound on said support, and (e) heating the supported chromium compound in a non-reducing atmosphere to form a supported chromium compound.
Claim 12
Dependent Claim
120 words
The supported chromium-oxide catalyst having as the support a porous, pure silica with a sodium content of at most about 200 ppm and a pore volume of at least about 1.0 cm 3 /g prepared by the process comprising the steps of (a) admixing to a non-porous silica prepared by the flame hydrolysis of a silica-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) spray drying said silica gel to form a catalyst support, (d) placing a chromium compound on said support, and (e) heating the supported chromium compound in a non-reducing atmosphere to form a supported chromium compound.
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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) | 1983-09-30 | 1984-03-31 | 1984-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-30 | 1988-03-31 | 1988-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-30 | 1992-03-31 | 1992-09-30 | $7700.00 | Window Closed / Lapsed |