Soda lime zirconia silicate glasses as prospective hosts for zirconia-containing radioactive wastes

Na₂O–CaO–ZrO₂–SiO₂ glass compositions with ZrO₂ contents of up to 20 mol% were melted. Up to 12.3 mol% ZrO₂ could be dissolved into the glasses. Melting temperatures ?1450 °C were required to remove seed and produce a melt that could be cast. Addition of ZrO₂ caused an increase in the glass transition and crystallization temperatures. Glasses crystallized at temperatures ?1050 °C with Keldyshite and Parakeldyshite (Na₂O · ZrO₂ · 2SiO₂) as the crystalline phases. Addition of up to 4.6 mol% ZrO₂ caused an increase in the hydrolytic resistance of the glass, with further additions having little effect. The suitability of these glasses as hosts for ZrO₂-containing radioactive wastes is discussed.