| 摘要 |
The invention provides a process for the preparation of a second composition, said process comprising the steps of: -preparing a first compositioncomprising an alkali metal magnesium orthosilicate andoptionally either(i) magnesium oxide or(ii) an alkali metal silicate, byreaction, at a temperature from 500 to 1200°C, of an alkali metal carbonate compound, which compound is an alkali metal carbonate, an alkali metal bicarbonate or a mixture thereof, with a magnesium silicate, the molar ratio of alkali metal carbonate compound, expressed as alkali metal oxide of the formula R 2 O, in which R represents an alkali metal, to magnesium silicate, expressed as silicon dioxide, of the formula SiO 2, being from 4:1 to 1:4, and -contacting the first composition with water to produce thesecond composition comprising an amorphous magnesium silicate hydrate (M-S-H). It is possible to isolateor producefurther useful products from the second composition. |
