| 摘要 |
A wet silica gel can be prepared by a process comprising the steps of contacting a stable, aqueous, fluid silica system having a pH greater than 7.5 with an ion exchange resin which removes metal ions and replaces them with H+ ions and thereby reduces the pH to less than 5.0, adding an organic liquid to the aqueous silica system, providing, however, that the organic liquid added stays in one phase with the aqueous, silica system, and does not cause the silica to precipitate, and adding a base to the silica system so that the pH of the silica system is in the range of from about 5.0 to about 7.5, and allowing the wet silica gel to form. The wet silica gel formed by this process is characterized by its high organic solvent content and the low concentration of basic metal ions.
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