SYNTHESIS OF PHILLIPSITE FROM FLY ASH

Phillipsite was synthesized from the silica-poor fly ash by the hydrothermal treatment with 2N-NaOH solution at 105°C. Most of phillipsite was synthesized between 2 hrs. and 6 hrs. in the reaction time. The phillipsite synthesis mainly depended on the Al concentration of the liquid phase, and was taken place from the dissolution of the silicate glass and the amorphous Al compound. The cation exchange capacity (CEC) of the synthesized phillipsite was 198 meq/100g. The suggested process of phillipsite synthesis was (1) the dissolution of amorphous materials and condensed compounds of fly ash, (2) the dissolution of the sphere matrix of fly ash particles, (3) the supersaturation of liquid phase, (4) the phillipsite formation, and (5) the growth of phillipsite crystal.