Patent US3857924A successfully refreshed from Google Patents.
US3857924A
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US
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Process for preparing silica particles
Assignee: Individual
•
Filing: 1972-11-02
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Granted: 1974-12-31
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Expires: 1992-11-02
Abstract
Abstract Substantially pure, spherical, porous silica particles are prepared by 1. TREATING AN ALKALI POLYSILICATE SOLUTION HAVING A SILICA CONTENT OF FROM 5 TO 7.5 PERCENT BY WEIGHT FIRST BATCHWISE WITH A CATION EXCHANGE MATERIAL TO REMOVE CATIONS; AND THEREAFTER BATCHWISE WITH AN ANION EXCHANGE MATERIAL TO REMOVE MINERAL ACIDS; 2. EMULSIFYING AND COAGULATING THE TREATED SOLUTION FROM (1) IN A WATER IMMISCIBLE ORGANIC MEDIUM THEREBY FORMING THE SILICA PARTICLES; AND 3. RECOVERING THE SILICA PARTICLES.
Inventors
- 👤 I Halasz
- 👤 I Sebestian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:53
CPC Classifications
B; B01; B01J; B01J21/00; B01J2/00; B01J2/02; B01J2/06; B01J2/08; B01J21/06; B01J21/08; C; C01; C01B; C01B33/00; C01B33/113; C01B33/12; C01B33/14; C01B33/141; C01B33/142; C01B33/143; C01B33/1435; C01B33/152; C01B33/154; C01B33/1546; C04; C04B; C04B35/00; C04B35/01; C04B35/14; Y; Y10; Y10S; Y10S516/00; Y10S516/922
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
147 words
PROCESS FOR PREPARING SUBSTANTIALLY PURE, SPHERICAL, POROUS SILICA PARTICLES HAVING A GRAIN SIZE IN THE RANGE OF 0.001 TO 3.0 MM AND A METAL OXIDE CONTENT OF LESS THAN 1.0 PERCENT BY WEIGHT WHICH COMPRISES A. TREATING ALKALI POLYSILICATE SOLUTION HAVING A SILICA CONTENT OF FROM 5 TO 7.5 PERCENT BY WEIGHT I. BATCHWISE BY MIXING AND STIRRING WITH A CATION EXCHANGE MATERIAL TO REMOVE CATIONS AND FILTERING OFF THE CATION EXCHANGE MATERIAL; AND II. THEREAFTER BATCHWISE BY MIXING AND STIRRING WITH AN ANION EXCHANGE MATERIAL TO REMOVE MINERAL ACIDS AND FILTERING OFF THE ANION EXCHANGE MATERIAL; B. EMULSIFYING AND COAGULATING THE TREATED SOLUTION FROM (A) IN A WATER IMMISCIBLE ORGANIC MEDIUM THEREBY FORMING SAID SILICA PARTICLES; AND C. RECOVERING SAID SILICA PARTICLES HAVING A GRAIN SIZE IN THE RANGE OF 0.001 TO 3.0 MM AND A METAL OXIDE CONTENT OF LESS THAN 1.0 PERCENT BY WEIGHT.
Claim 2
Dependent Claim
147 words
PROCESS FOR PREPARING SUBSTANTIALLY PURE, SPHERICAL, POROUS SILICA PARTICLES HAVING A GRAIN SIZE IN THE RANGE OF 0.001 TO 3.0 MM AND A METAL OXIDE CONTENT OF LESS THAN 1.0 PERCENT BY WEIGHT WHICH COMPRISES A. TREATING ALKALI POLYSILICATE SOLUTION HAVING A SILICA CONTENT OF FROM 5 TO 7.5 PERCENT BY WEIGHT I. BATCHWISE BY MIXING AND STIRRING WITH A CATION EXCHANGE MATERIAL TO REMOVE CATIONS AND FILTERING OFF THE CATION EXCHANGE MATERIAL; AND II. THEREAFTER BATCHWISE BY MIXING AND STIRRING WITH AN ANION EXCHANGE MATERIAL TO REMOVE MINERAL ACIDS AND FILTERING OFF THE ANION EXCHANGE MATERIAL; B. EMULSIFYING AND COAGULATING THE TREATED SOLUTION FROM (A) IN A WATER IMMISCIBLE ORGANIC MEDIUM THEREBY FORMING SAID SILICA PARTICLES; AND C. RECOVERING SAID SILICA PARTICLES HAVING A GRAIN SIZE IN THE RANGE OF 0.001 TO 3.0 MM AND A METAL OXIDE CONTENT OF LESS THAN 1.0 PERCENT BY WEIGHT.
Claim 3
Dependent Claim
11 words
Process of claim 1 wherein said alkali polysilicate is sodium silicate.
Claim 4
Dependent Claim
12 words
Process of claim 1 wherein the organic medium is a neutral oil.
Claim 5
Dependent Claim
19 words
Process of claim 3 wherein said neutral oil has a viscosity in the range of 4 to 40 centiposie.
Claim 6
Dependent Claim
19 words
Process of claim 1 wherein stirring at a speed of 200 to 900 RPM is utilized in step (b).
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) | 1977-12-30 | 1978-07-01 | 1978-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-30 | 1982-07-01 | 1982-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-30 | 1986-07-01 | 1986-12-31 | $7700.00 | Window Closed / Lapsed |