Studies on the separation and in-situ sintering solidification of strontium by a highly-efficient titanate-based adsorbent
Studies on the separation and in-situ sintering solidification of strontium by a highly-efficient titanate-based adsorbent
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高效钛酸盐基吸附剂分离锶及原位烧结固化研究
DOI：
10.1016/j.micromeso.2019.109607
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发表时间：
2019-11-01
影响因子：
5.2
通讯作者：
Wei, Yuezhou
中科院分区：
文献类型：
--
作者：
Li, Chunmin;Liu, Caocong;Wei, Yuezhou
核事故和日常核电站是锶（Sr 2+）的主要释放源，从水溶液中去除锶已引起人们的高度重视。在各种修复方法中，吸附法以其成本低、去除效率高、操作简单等优点被广泛应用于水溶液中有害离子的去除。然而，吸附剂在处理有害离子后可能会产生二次固体废弃物，这给处理过程增加了麻烦和挑战。采用改进的溶胶-凝胶法制备了钛酸钠粉体（Na 2 TinO 2n +1）。X射线衍射（XRD）结果表明，Na 2 TinO 2n +1在400 ℃煅烧10 h后转变为层状结构。合成的吸附剂比表面积（BET）为65.01m2/g。静态吸附实验结果表明，Na 2 TinO 2n +1是一种很有前途的吸附剂，其最大吸附容量可达49.6mg/g，对Ba ~（2+）共存离子中的Sr ~（2+）具有很高的选择性。Ca ~（2+）、Mg ~（2+）、Cs ~（2+）、K ~（+），其亲合力大小顺序为Sr ~（2+）> Ba ~（2+）> CO ~（2+）> Mg ~（2+）> Cs ~（2+）> K ~（+）。在固化阶段，Sr-Na 2 TinO 2n +1吸附剂在40 Mp下冷压，然后在1100 ℃下煅烧成钛酸盐陶瓷（Na-Sr-TinO 2n +1）。钛酸盐陶瓷在不同介质中的浸出实验表明，钛酸盐陶瓷对吸附的Sr ~（2+）具有良好的固化能力。
Nuclear accident and daily nuclear plants are the main strontium (Sr2+) releasing source and the removal of strontium from aqueous solution has aroused great attention. Among the different remediation ways, adsorption with the properties of low cost, high-removal efficiency, and excellent operational simplicity is intensively adopted in the removal of hazard ions in aqueous solution. However, adsorbent could be accumulated and might cause secondary solid wastes after the treatment of hazard ions, which increases troubles and challenges in the disposal process. In this work, a sodium titanate powder (Na2TinO2n+1) was prepared by an improved sol-gel method. The X-ray diffraction (XRD) demonstrates that Na2TinO2n+1 is transformed into anatase structure after calcining at 400 degrees C for 10 h. The specific surface area (BET) of the synthesized adsorbent is 65.01 m(2)/g. The results of batch adsorption experiments reveal that Na2TinO2n+1 is a promising adsorbent for removing Sr2+, which the maximum adsorption capacity could achieve to 49.6 mg/g, The adsorbent also shows high selectivity towards Sr2+ in the co-existence ions of Ba2+., Ca2+, Mg2+, Cs+, K+, and the affinity order is Sr2+ > Ba2+ > CO2+ > Mg2+ > Cs+ > K+. In the solidification stage, Sr-Na2TinO2n+1 adsorbent is cold pressed at 40Mp and then calcined into titanate ceramics (Na-Sr-TinO2n+1) at 1100 degrees C. The leaching experiment of titanate ceramics on various medium exhibits excellent solidification capability towards adsorbed Sr2+.