Preparation of Porous Aggregates of Smectite by Spray Drying Combined with the Intercalation of a Water-soluble Polymer

Donut shaped porous aggregates of a smectite with the size of several tens of micron were obtained by the spray drying of an aqueous suspension of the clay containing a block copolymer, P123. After calcination at 500 °C, the donut shape was retained and the BET surface area of the calcined product was ca. 200 m2/g, which was much higher than the product prepared without using P123. The roles of P123 for the formation of porous aggregate were discussed as the increased viscosity leading to the donut shaped aggregates by the spray drying and the suppression of the collapsing of the layered structure by the calcination.