| 摘要 |
<p>A process for the synthesis of a smectite type mineral such as hectorite comprising the formation of a solid reaction product containing the magnesium and silicon values of the hectorite by the precipitation of at least a proportion of the said values under basic conditions to form a precursor and the subsequent treatment of the said precursor under hydrothermal conditions to achieve crystallisation of a product having a hectorite structure and the separation and washing of that product, the process being characterised in that the pH under which the precipitation is conducted is controlled at from 7.5 to 9 or from 9.7 to 10 to improve processing or performance characteristics for example, the washing time, the rate of dispersion, the clarity dispersion, the time to gel or the gel strength. The product is suitable for a wide variety of applications as a rheological additive.</p> |
