Ion Exchange Capacity and Phase Separation of Alkali Borosilicate Glass by Substituting <TEX>$Al_2O_3$</TEX>

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J. Korean Ceram. Soc. > Volume 21(1); 1984 > Article

Journal of the Korean Ceramic Society 1984;21(1): 41.

산화알루미늄의 치환에 따른 붕규산 유리의 분상 미 이온교환성에 관한 연구

김병호, 유영문

고려대학교 재료공학과

Ion Exchange Capacity and Phase Separation of Alkali Borosilicate Glass by Substituting $Al_2O_3$

ABSTRACT

The ion-exchange porous glasses were prepared by heat treating and subsequently acid treating the (95-y) $SiO_2$.$yB_2O_3$.$5Na_2O+xAl_2O_3$ glasses with y=55, 45, 35, 25. mole% and x=0, 2, 5, 9 mole% It was then investigated how the cation exchange capacity was affected by the phase separation in these glasses. For that matter such quantities as alkali extraction amount pore volume and specific surface area of the glasses were measured. The phase separation in these glasses was in general suppressed by the addition of $Al_2O_3$ maximally around the composition of 5 mole% $Al_2O_3$ This may be because the micro-phase separation prevailed in the glass of that composition over the macro-phase separation increasing thereby the specific surface area as well as the residual amount Al of after acid-treatment and accordingly the cation exchange capacity. The maximum values of the cation exchange capacity was observed to be about 150meq/100g for the glasses of (40-50) $SiO_2$ (55~45)$yB_2O_3$. $5Na_2O+5Al_2O_3$