Claims
- 1. A method for producing synthetic magadiite, comprising the step of: heating a liquid aqueous colloidal silica suspension, the liquid aqueous colloidal silica suspension having a mole ratio of sodium hydroxide to silica and a mole ratio of water to silica effective to produce a synthetic magadiite wherein more than fifty percent by weight of the synthetic magadiite is platy synthetic magadiite.
- 2. The method of claim 1, wherein the mole ratio of sodium hydroxide to silica is in the range of from about 0.4 to about 0.5, the mole ratio of water to silica is in the range of from about 5 to about 39.
- 3. The method of claim 1, wherein the mole ratio of sodium hydroxide to silica is in the range of from about 0.48 to about 0.52, the mole ratio of water to silica is in the range of from about 25 to about 39.
- 4. Synthetic magadiite wherein more than fifty percent by weight of the synthetic magadiite is platy magadiite.
- 5. Synthetic magadiite wherein more than eighty percent by weight of the synthetic magadiite is platy magadiite.
- 6. Synthetic magadiite wherein more than ninety percent by weight of the synthetic magadiite is platy magadiite.
- 7. Silica gel made by contacting the synthetic platy magadiite of claims 4, 5 or 6 with an acid in an aqueous liquid.
- 8. Silica gel made by contacting the synthetic platy magadiite of claims 4, 5 or 6 with colloidal silica and an acid in an aqueous liquid.
- 9. The synthetic platy magadiite of claims 4, 5 or 6 wherein at least a portion of the sodium ions of the synthetic platy magadiite are exchanged for hydrogen ions to produce acidified synthetic platy magadiite.
- 10. The synthetic platy magadiite of claim 9, wherein more than ninety percent of the sodium ions of the synthetic platy magadiite are exchanged for hydrogen ions to produce acidified synthetic platy magadiite.
- 11. The acidified synthetic platy magadiite of claim 10, sufficiently heated to drive off water from the acidified synthetic platy magadiite to form silica plates.
- 12. The acidified synthetic platy magadiite of claims 9 or 10, wherein the surface hydroxyls of the acidified synthetic platy magadiite are alkylated.
- 13. The synthetic platy magadiite of claim 12, wherein the surface hydroxyls of the acidified synthetic platy magadiite are butylated.
- 14. A method for the production of platy sodium octasilicate, comprising the step of: heating a liquid aqueous colloidal silica dispersion containing silica, sodium oxide, and water, the mole ratio of the silica to the sodium oxide being in the range of from about 3.5 to about 10.
- 15. The method of claim 14, wherein the temperature is in the range of from about 80 to about 125 degrees Celsius and the mole ratio of the silica to the sodium oxide is in the range of from about 4 to about 6.
- 16. The method of claim 14, wherein the temperature is in the range of from about 95 to about 115 degrees Celsius and the mole ratio of the silica to the sodium oxide is in the range of from about 4.3 to about 5.2.
- 17. The method of claim 14, wherein the temperature is in the range of from about 100 to about 110 degrees Celsius and the mole ratio of the silica to the sodium oxide is in the range of from about 4.5 to about 4.7.
- 18. A method for preparing a liquid aqueous colloidal silica dispersion, the dispersion having a mole ratio of silica to sodium oxide of from 3.5 to 10, comprising the step of: mixing a sufficient amount of liquid aqueous colloidal silica suspension with a liquid aqueous sodium silicate suspension to produce the liquid aqueous colloidal silica dispersion, the liquid aqueous colloidal silica suspension having a mole ratio of silica to sodium oxide of more than 20, the liquid aqueous sodium silicate suspension having a mole ratio of silica to sodium oxide of less than 3.5, the rate of mixing being effective to prevent the gellation or solidification of the liquid aqueous colloidial silica dispersion.
- 19. The method of claim 18, wherein the liquid aqueous colloidal silica dispersion has a mole ratio of silica to sodium oxide of from 4 to 10.
- 20. The method of claim 18, wherein the liquid aqueous colloidal silica dispersion has a mole ratio of silica to sodium oxide of from 4 to 6.
- 21. The method of claim 18, wherein the liquid aqueous colloidal silica dispersion has a mole ratio of silica to sodium oxide of from 4.5 to 5.2.
- 22. The method of claim 18, wherein the liquid aqueous colloidal silica dispersion has a mole ratio of silica to sodium oxide of from 4.5 to 4.7.
GOVERNMENT CONTACT
[0001] This application is under a Government contract with The Department of Commerce (NIST)—Advanced Technology Program Project #70NANB7H3028.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/US01/11978 |
4/12/2001 |
WO |
|