Solidification and stabilization of strontium and chloride ions in thermally treated calcium aluminate cement modified with or without sodium polyphosphate
Solidification and stabilization of strontium and chloride ions in thermally treated calcium aluminate cement modified with or without sodium polyphosphate
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DOI：
10.1016/j.cemconres.2022.106758
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发表时间：
2022
影响因子：
11.4
通讯作者：
K. Irisawa;M. Namiki;T. Taniguchi;I. García-Lodeiro;H. Kinoshita
中科院分区：
文献类型：
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作者：
K. Irisawa;M. Namiki;T. Taniguchi;I. García-Lodeiro;H. Kinoshita
由于水含量的潜在辐解，被显著的90 Sr污染的含水放射性废物的胶结是具有挑战性的。用聚磷酸钠（CAP）改性的铝酸钙水泥（CAC）的使用是令人感兴趣的，因为其水含量可以通过热处理来降低。本研究调查固化和稳定的Sr2+和Cl−离子在CAC和CAP与或不热处理。浸出试验表明，上级Sr 2+离子稳定CAP：Sr 2+的表观扩散系数小于5个数量级的CAC。在测试的样品中，在20 °C下固化的CAC对Cl−离子具有最好的稳定性。CAC中形成的Friedel盐可能有助于固定Cl−离子。CAP对Cl−离子的稳定性通过热处理显著提高，这可能是因为先前报道的微观结构的改善。
Cementation of aqueous radioactive waste contaminated with a significant90Sr is challenging due to the potential radiolysis of water contents. Utilization of calcium aluminate cement (CAC) modified with sodium polyphosphate (CAP) is interesting as its water content can be reduced by thermal treatment. The present study investigated solidification and stabilization of Sr2+and Cl−ions in CAC and CAP with or without thermal treatment. A leaching test showed a superior Sr2+ion stabilization in CAP: apparent diffusion coefficient of Sr2+was smaller than in the CAC by 5 orders of magnitude. CAC cured at 20 °C had the best stabilization for Cl−ions among the samples tested. Friedel's salt formed in CAC may have contributed to the immobilization of Cl−ions. The stabilization of Cl−ions by CAP was significantly improved by the thermal treatment likely because of the improvement in the microstructure previously reported.