Abstract:

In the high-level radioactive waste liquid separation process of spent fuel reprocessing, new separation materials are of great significance for the efficient extraction of strontium. In the paper, 1, 2-alternate thiacalix[4]biscrowns 4 (TCACE) was synthesized by using calix[4]arene and triethylene glycol di(p-toluenesulfonate). TCACE was characterized by FT-IR, ¹H NMR and MS. The influence of different diluents on extraction rate was studied, and CH₂Cl₂ was chosen as diluent by optimization. Extraction rate of Sr²⁺ was excellent and average mass transfer coefficient was 1.36×10^{-5 m}·s^-1 under the conditions of CH₂Cl₂ as organic solvent, nitrate acid concentration was 3 mol·L^-1, TCACE concentration was 1×10^-3 mol·L^-1, Sr²⁺ concentration was 5×10^-4 mol·L^-1, extraction was conducted for 80 min and at 25℃. Different technological conditions on extraction for Sr²⁺ were studied. Furthermore, the extraction measurement equation was also studied. The extraction complex was {Sr(NO₃)₂}·{TCACE} as shown by experiment. The extraction effects for other metal ions Mo⁶⁺, Ni²⁺, Ag⁺, Sn⁴⁺ with TCACE were also studied. It was found that TCACE showed excellent selectivity for Sr²⁺.

Key words: thiacalix[4]arene-biscrowns 4, synthesis, Sr²⁺, extraction, separation

摘要：

乏燃料后处理的高放废液分离过程中,发展新型分离材料实现对锶的高效萃取至关重要。合成了1,2交替构象的硫代杯[4]冠-4(TCACE),利用FT-IR、¹H NMR和MS对目标产物进行了表征。研究不同稀释剂对萃取的影响,优化得出CH₂Cl₂为稀释剂,在硝酸浓度为3 mol·L^-1,有机相中硫代杯[4]冠-4浓度为1×10^-3 mol·L^-1,水相中Sr²⁺浓度为5×10^-4 mol·L^-1,萃取温度为25℃,萃取80 min条件下,平均传质系数为1.36×10^{-5 m}·s^-1,Sr²⁺的分配比为0.69。分析了不同条件对硫代杯[4]冠-4对Sr²⁺的萃取影响,研究了萃取计量方程式,实验结果表明萃合物为{Sr(NO₃)₂}·{TCACE}。研究了TCACE对其他金属离子Mo⁶⁺、Ni²⁺、Ag⁺、Sn⁴⁺等的萃取效果,表明对Sr²⁺具有较好的选择性。

关键词: 硫代杯[4]冠-4, 合成, Sr²⁺, 萃取, 分离