US4011302A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing highly absorbent, low bulk density sodium silicate
Assignee: DU PONT AND POWER SILICATES Inc A CORP OF
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Filing: 1975-06-26
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Granted: 1977-03-08
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Expires: 1995-06-26
Abstract
Abstract A process for preparing low bulk density, highly absorbent, amorphous, hydrous, water-soluble alkali metal silicate particles having high internal porosity by spray drying a mixture of an aqueous sodium or potassium silicate solution and hydrogen peroxide.
Inventors
- 👤 Mohamed Defrawi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:38
CPC Classifications
C; C11; C11D; C11D3/00; C11D3/02; C11D3/04; C11D3/08; C01; C01B; C01B33/00; C01B33/20; C01B33/32; C01B33/325
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
147 words
A process for the preparation of a water-soluble, highly absorbent, sodium or potassium silicate comprising mixing an aqueous alkali metal silicate selected from sodium silicate and potassium silicate having a mole ratio of silica to sodium or potassium oxide of from 2:1 to 3.5:1 with a 20 to 100% by weight hydrogen peroxide aqueous solution to form a mixture with a viscosity sufficiently low to pass through the spray dryer nozzle without preheating and spray drying the mixture having a 5 to 20% by weight hydrogen peroxide content based on the weight of alkali metal silicate at a temperature of from about 450° to about 800° F and collecting a sodium or potassium silicate product having a water content of from 12 to 22% by weight, a bulk density of 0.1 g/cc to 0.3 g/cc and an absorbency of 50 to 200% based on the OSB test.
Claim 2
Dependent Claim
147 words
A process for the preparation of a water-soluble, highly absorbent, sodium or potassium silicate comprising mixing an aqueous alkali metal silicate selected from sodium silicate and potassium silicate having a mole ratio of silica to sodium or potassium oxide of from 2:1 to 3.5:1 with a 20 to 100% by weight hydrogen peroxide aqueous solution to form a mixture with a viscosity sufficiently low to pass through the spray dryer nozzle without preheating and spray drying the mixture having a 5 to 20% by weight hydrogen peroxide content based on the weight of alkali metal silicate at a temperature of from about 450° to about 800° F and collecting a sodium or potassium silicate product having a water content of from 12 to 22% by weight, a bulk density of 0.1 g/cc to 0.3 g/cc and an absorbency of 50 to 200% based on the OSB test.
Claim 3
Dependent Claim
29 words
The process of claim 1 wherein the viscosity of the mixture of silicate solution and peroxide solution is from 10 to 300 centipoises as measured with an Oswald viscometer.
Claim 4
Dependent Claim
13 words
The process of claim 2 wherein the viscosity is 50 to 150 centipoises.
Claim 5
Dependent Claim
13 words
The process of claim 1 wherein the temperature is 500° to 700° F.
Claim 6
Dependent Claim
19 words
The process of claim 1 wherein the water content of the silicate product is 14 to 20% by weight.
Claim 7
Dependent Claim
13 words
The process of claim 1 wherein the alkali metal silicate is sodium silicate.
Claim 8
Dependent Claim
13 words
The process of claim 1 wherein the alkali metal silicate is potassium silicate.
References Cited (Backward Citations)
US3838192A
Cited
US3932140A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-07 | 1980-09-06 | 1981-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-07 | 1984-09-06 | 1985-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-07 | 1988-09-06 | 1989-03-08 | $7700.00 | Window Closed / Lapsed |