CLAY WITH HIGH SPECIFIC SURFACE AREA FOR PRODUCING BLEACHING EARTH , AS WELL AS METHOD OF ACTIVATING SAID CLAY Russian patent published in 2010 - IPC B01J20/12 

FIELD: chemistry.

SUBSTANCE: invention relates to clay sorbents. Described is a method of preparing an adsorbent, an adsorbent prepared using said method, as well as its use as bleaching earth, particularly for refining oil and fats. According to the invention, the method uses unbaked clay with specific surface area ranging from 200 to 280 m²/g, ion-exchange capacity of not more than 40 meq/100 g and pore volume from 0.7 to 1.0 ml/g, where at least 40% of the pore volume is formed by pores with diametre of at least 14 nm, and at most 25% of the pore volume is formed by pores with diametre less than 7.5 nm. Content of AI₂O₃ in terms of anhydrous clay is less than 11 wt % and content of SiO₂ in terms of anhydrous clay is more than 65 wt %. The clay is activated with inorganic acid, obtaining an adsorbent with bleaching power.

EFFECT: invention allows for selecting suitable natural clay and obtaining a product from it with bleaching power which surpasses bleaching power of highly active bleaching earth obtained via intense dealumination and washing with strong acid.

16 cl, 4 ex, 7 tbl, 1 dwg