【摘要】 对二（2-乙基己基）亚砜（DEHSO）和磷酸三丁酯（TBP）萃取Th、U的性能进行了比较,研究了水相HNO₃浓度、萃取剂浓度、温度等因素对萃取Th、U的影响。DEHSO与U、Th和HNO₃形成的萃合物为UO₂（NO₃）₂·2DEHSO,Th（NO₃）₄·2DEHSO和HNO₃·DEHSO。在本实验浓度条件下测得萃取U、Th及NHO₃反应的平衡常数为14.9、0.027、0.13,U、Th萃取反应的热焓为-44.30和-42.50kJ/mol。同时试验了有机相中U（Ⅵ）和Th（Ⅳ）的反萃。更多还原

【Abstract】 A study on extraction of U(Ⅵ) and Th(Ⅳ) from nitric acid media by DEHSO and TBP is described. The distribution ratio of U(Ⅵ) from nitric acid medium by DEHSO is higher than by TBP, while the distribution ratio of Th(Ⅳ) is about the same for DEHSO and TBP. Therefore DEHSO exhibits a higher U-Th separation factor than TBP. The extraction reaction for U(Ⅵ) and Th(Ⅳ) is exoergic and the compositions of extracted species are UO2(NO3)2 2DEHSO and Th(NO3)4 2DEHSO. The back extraction of U(Ⅵ) and Th(Ⅳ) from DEHSO or TBP by 0.01-0.1 mol/1 HNO3 is also studied.更多还原