Presently, the bentonite clays are the popular materials which used in the adsorption refining. The bentonite is characterized by the extensive surface, the high mechanical strength, also it is the cheap and affordable material. In comparison with another cheap natural sorbents, the bentonites are differenced by the high sorption capacity towards to the anions of the various salts. However, the natural bentonite undergoes modification for more effective purification.
