Claims
- 1. Heat treated precipitated silica particulates having a BET surface area of from 100 to 350 m.sup.2 /g and a CTAB surface area of from 100 to 350 m.sup.2 /g the water uptake of said particulates, without treatment with a hydrophobization agent, being no greater than about 4.5%.
- 2. The precipitated silica particulates as defined by claim 1, having a BET surface area of from 135 to 350 m.sup.2 /g, and a CTAB surface area of from 150 to 350 m.sup.2 /g.
- 3. The precipitated silica particulates as defined by claim 1, essentially spheroidal in configuration and having a mean particle size greater than 80 .mu.m.
- 4. The precipitated silica particulates as defined by claim 1, said water uptake without treatment with a hydrophobization agent being no greater than about 3%.
- 5. The precipitated silica particulates as defined by claim 1, having a residual sodium content no greater than 1,500 ppm.
- 6. The precipitated silica particulates as defined by claim 1, having a residual sodium content no greater than 1,000 ppm.
- 7. The precipitated silica particulates as defined by claim 5, having a carbon content of less than 2,500 ppm.
- 8. The precipitated silica particulates as defined by claim 5, having a carbon content of less than 500 ppm.
- 9. The precipitated silica particulates as defined by claim 3, having a mean particle size greater than 150 .mu.m.
- 10. The precipitated silica particulates as defined by claim 3, having a mean particle size ranging from 200 to 300 .mu.m.
- 11. The precipitated silica particulates as defined by claim 1, having a density ranging from 0.23 to 0.32.
- 12. The precipitated silica particulates as defined by claim 2, having a density of at most 0.3.
- 13. The precipitated silica particulates as defined by claim 2, having a density of at most 0.15.
- 14. The precipitated silica particulates as defined by claim 12, having a pH ranging from 3.5 to 7.5.
- 15. The precipitated silica particulates as defined by claim 12, having a pH ranging from 4.5 to 6.5.
- 16. The precipitated silica particulates as defined by claim 14, no more than 0.05% thereof being retained on a 45 .mu.m mesh screen.
- 17. The precipitated silica particulates as defined by claim 12, having a ratio of BET surface area/CTAB surface area ranging from 0.9 to 1.2.
Priority Claims (1)
Number |
Date |
Country |
Kind |
87 02478 |
Feb 1987 |
FRX |
|
Parent Case Info
This application is a continuation of application Ser. No. 07/160,346, filed Feb. 25, 1988, now abandoned.
US Referenced Citations (8)
Foreign Referenced Citations (4)
Number |
Date |
Country |
0018866 |
Nov 1980 |
EPX |
1056218 |
Nov 1080 |
FRX |
1111969 |
Mar 1956 |
FRX |
2075083 |
Oct 1971 |
FRX |
Continuations (1)
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Number |
Date |
Country |
Parent |
160346 |
Feb 1988 |
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