Alkali aluminosilicate geopolymers as binders to encapsulate strontium-selective titanate ion-exchangers. Issue 32 (22nd July 2019)

• Record Type: Journal Article
• Authors: Ke, Xinyuan; Bernal, Susan A.; Sato, Tsutomu; Provis, John L.
• Is Part Of: Dalton transactions. Volume 48:Issue 32(2019)
• Page Start: 12116
• Page End: 12126
• Publication Date: 2019-07-22
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c9dt02108f
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Geopolymer cements can be used to solidify strontium-contaminated ion exchanger particles, forming a stable monolith potentially suitable for final disposal. Abstract : Alkali-activated metakaolin geopolymers are attracting interest in the conditioning of nuclear wastes, especially for their ability to immobilise cationic species. However, there is limited understanding of the chemical interactions between the encapsulated spent ion-exchangers, used for decontaminating waste water, and the host aluminosilicate matrix. The lack of such understanding makes it difficult to predict the long-term stability of the waste form. In this study, the suitability of using metakaolin based geopolymer as a matrix for encapsulation of titanate-type ion-exchangers loaded with non-radioactive Sr was investigated for the first time, via spectroscopic and microstructural inspection of the encapsulated ion-exchangers and the aluminosilicate gel matrix. The microstructural and chemical properties of metakaolin geopolymers remained stable after encapsulating titanate type spent ion-exchangers, performed desirably as host materials for conditioning of Sr-loaded titanate ion-exchangers.