Abstract
Methods of purifying sepiolite-paygorskite series were reviewed and discussed under the two purification categories: extraction of elements and elimination of minerals.
A number of previous works focused on the extraction of elements from sepiolite by acid treatment because knowledge gained from basic studies on dissolution kinetics, structural changeand surface properties, and/or application studies for fillers and catalysts can be applied to such treatments.
On the other handmethods for the elimination of impurity minerals have developed followiong more empirical approaches using elutiation and/or acid treatment.Recentlybasic works on selective dissolution of carbonate in sepiolite-ore has been developed. Importance of the pH control in accordance with a solubility diagram was emphasized.
