Claims
- 1. A method of producing loosely aggregated silica having an average primary particle size in the range of 200 to 500 millimicrons comprising adding an alkali metal silicate solution to an ammoniated gelling solution selected from the group consisting of an ammoniated formic acid solution, an ammoniated acetic acid solution, an ammoniated propionic acid solution and an ammoniated carbonic acid solution, said ammoniated gelling solution containing a substantial excess of ammonia and having a pH of 10 to 11, to form a slurry of said loosely aggregated silica and recovering said loosely aggregated silica.
- 2. A method as in claim 1 wherein said loosely aggregated silica is washed with an acidic solution and dried.
- 3. A method as in claim 1 wherein said loosely aggregated silica is deaggregated by passage through a fluid energy mill operated at 25.degree. C. to 350.degree. C. and 25 to 225 psi pressure.
- 4. A method as in claim 1 wherein said ammoniated solution is an ammoniated acetic acid solution.
- 5. A method as in claim 1 wherein said ammoniated solution is an ammoniated carbonic acid solution.
- 6. The method of claim 1 wherein said alkali metal silicate solution contains about 4 to 20 percent by weight SiO.sub.2.
Parent Case Info
This is a continuation-in-part of U.S. Application Ser. No. 412,359, filed Nov. 2, 1973, which in turn is a continuation-in-part application of U.S. Application Ser. No. 156,088, filed June 23, 1971, both now abandoned.
US Referenced Citations (7)
Continuation in Parts (2)
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Number |
Date |
Country |
Parent |
412359 |
Nov 1973 |
|
Parent |
156088 |
Jun 1971 |
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