Vitreous and crystalline phosphate high level waste matrices: Present status and future challenges

Vitreous and crystalline phosphate high level waste matrices: Present status and future challenges

Vitrification is currently the most effective process for immobilization of nuclear waste. However,ubiquitous borosilicate glass is not suitable for immobilization of nuclear waste from advanced reactorssuch as Fast Breeder Reactors (FBR) because solubility of many compounds/elements existing in the spentfuel in borosilicate glasses is quite poor. In order to possess a viable immobilization strategy for wastesarising from advanced reactors, alternatives to borosilicate glasses such as phosphate glasses, glassceramicsand crystalline waste forms are being investigated. This review aims to provide an overview ofnuclear waste immobilization employing phosphate-based glasses, glass-ceramics and crystallineceramic hosts, focusing on structure and properties that make these new matrices suitable for thechallenging task of waste immobilization.

Vitrification is currently the most effective process for immobilization of nuclear waste. However,ubiquitous borosilicate glass is not suitable for immobilization of nuclear waste from advanced reactorssuch as Fast Breeder Reactors (FBR) because solubility of many compounds/elements existing in the spentfuel in borosilicate glasses is quite poor. In order to possess a viable immobilization strategy for wastesarising from advanced reactors, alternatives to borosilicate glasses such as phosphate glasses, glassceramicsand crystalline waste forms are being investigated. This review aims to provide an overview ofnuclear waste immobilization employing phosphate-based glasses, glass-ceramics and crystallineceramic hosts, focusing on structure and properties that make these new matrices suitable for thechallenging task of waste immobilization.