The dynamics of acid treatment in the preparation of porous glass

Abstract

The phase-separation glasses with composition of Na₂O (9.0) B₂O₃ (25.0)-SiO₂ (66.0) (in mode ratio) were leached with hydrochloric acid, and porous glasses were prepared. The dynamis of the acid treatment was investigated. The effects of treatment time, temperature and acid concentration on the acid treatment process were studied using HCl as treatment solution. The dynamics equation and apparent activation energy obtained in acid treatment process were

$dw/dt = \sqrt {} a/2\sqrt t $\end{document}

and E=57.74 kJ·mol⁻¹, respectively. The constants of the reaction rate at different temperatures were calculated. On the basis of experimental data the mechanism of acid treatment process and the source of swollen stress, which was the main stress during treatment process, were discussed.

Keywords

porous glass / phase-separation glass / dynamics of reaction / diffusion

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