• Journal of the Korean Ceramic Society
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• v.25 no.1
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• pp.59-65
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• 1988

To develop porous glass membranes used for a effective membrane-separation process, porous glasses and glass membranes were prepared from the sodium borosilicate parent glass by the phaseseparation technique and effects of heat-treatment and leaching conditions on their characteristics were investigated. The crack-free glass membranes could be fabricated from the 9.4 Na2-O-30.7 B2O3-59.2 SiO2-0.7 Al2O3(wt%) parent glass by heat-treatment at the lower temperature(550-570$^{\circ}C$) and for longer than 45 hrs for the phase separation, followed by leaching with 3N-HCl＋60% ethylene glycol solution at 90$^{\circ}C$ over 25 hrs. Porous glasses prepared in this work showed large specific surface areas(400㎡/g) and narrow pore size distribution with the mean pore radius of 14${\AA}$ enough for the application as reverse osmosis membranes. The salt-rejection efficiency and product-flux of the glass membranes heat-treated at 570$^{\circ}C$ for 80 hrs were found to be 51.8% and 270cc/㎡. hr, respectively. This result suggests that the porous glass membranes fabricated in this study could be applied for the reverse osmosis process.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.1
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• pp.57-65
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• 2005

This study suggested a new method for the solidification of molten salt waste generated from the electro-metallurgical process in the spent fuel treatment. Using binary material system, sodium silicate and phosphoric acid, metal chlorides were converted into metal phosphate in the micro-reaction module formed by SiO$_{2} particles. The volatile element in the reaction module would little vaporized below 1100$^{circ}$C After the gel product was mixed with borosilicate glass powder and thermally treated at 1000$^{circ}$C, li exists as Li$_{3}$PO$_4$ separated from glass phase and, Cs and Sr would be incorporated into an amorphous phase from XRD analysis. In case of the addition of ZrCl$_{4}$ to the binary system, the gel products were transformed into NZP structure considered as an prospective ceramic waste form after heat-treatment above 700 $^{circ}$C. From these results, the gel-route pretreatment can be considered as an effective approach to the solidincation of molten salt waste by the confirmed process or waste form and this also would be an alternative method on the ANL method using zeolites in USA by the confirmation of its chemical durability as an future work.