| 摘要 |
The invention pertains to a process for preparing a synthetic clay mineral which comprises silicon, aluminum, and at least one octahedron ion, which clay mineral has a total content of sodium and potassium of less than 0.5 wt. %, comprising the steps ofa) providing a silica-alumina with a total content of sodium and potassium of less than 2.0 wt. %b) combining the silica-alumina with an octahedron ion source in such a manner that less than 0.1 mole of the total of sodium or potassium is added per mole of octahedron ion,c) if necessary, adjusting the pH to a value of at least 7, with less than 0.1 mole of the total of sodium and potassium being added per mole of octahedron ion during the pH adjustment,d) ageing the precipitate formed in c) at a temperature of 0-350° C. in an aqueous environment;e) optionally isolating the resulting material, optionally followed by washing.The invention makes it possible to prepare a saponite with a low content of sodium and potassium without an ion-exchange on the final material being necessary. |
