Cextrant 230/二异辛基琥珀酸酯磺酸钠/正庚烷反相微乳液萃取钍  

Extraction of Thorium(Ⅳ) Using Cextrant 230/Anionic Surfactant Sodium Bis(2-Ethylhexyl)Sulfosuccinate/n-Heptane Microemulsion

作　　者：李艳玲[1,2] 邝圣庭[1,3] 廖伍平 LI Yan-Ling;KUANG Sheng-Ting;LIAO Wu-Ping(State Key Laboratory of Rare Earth Resource Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China;School of Applied Chemistry and Engineering,University of Science and Technology of China,Hefei 230026,China;Ganjiang Innovation Academy,Chinese Academy of Sciences,Ganzhou 341000,China)

机构地区：[1]中国科学院长春应用化学研究所,稀土资源利用国家重点实验室,长春130022 [2]中国科学技术大学,应用化学与工程学院,合肥230026 [3]中国科学院赣江创新研究院,赣州341000

出　　处：《应用化学》2022年第12期1927-1936,共10页Chinese Journal of Applied Chemistry

基　　金：国家重点研发计划(No.2019YFC0605003);中国科学院战略先导(No.XDA02030100);江西“双千计划”(No.jxsq.2020101005)资助。

摘　　要：选取α-氨基膦酸酯萃取剂Cextrant 230和阴离子表面活性剂二异辛基琥珀酸酯磺酸钠(AOT)/正庚烷和水形成稳定的反向微乳液,考察了Cextrant 230-AOT-正庚烷微乳体系最大含水比x0与Cextrant 230浓度、AOT浓度、水相酸度、NaOH浓度及硫酸盐浓度的关系,分析了微乳液的形成过程及影响,并确定合适的实验条件。将Cextrant 230-AOT-正庚烷微乳体系用于钍的萃取,研究了微乳液与水相体积比、Cextrant 230和AOT浓度、硫酸盐浓度、温度等因素对钍萃取率的影响。结果表明,在微乳液体系中钍的萃取率随着Cextrant 230(或AOT)浓度的增加而增大,萃取效果明显高于AOT-正庚烷微乳体系,Cextrant 230与AOT对钍的萃取有协同效应;温度对钍的萃取影响较小,反应由熵驱动;比较了不同种类无机酸的反萃效果,选择硫酸作反萃剂;确定了微乳液体系对钍的萃取饱和容量为1.43 g/L;经两次错流萃取可将氟碳铈矿硫酸浸出液(已预先分离铈)中钍含量降至0.1 mg/L以下。该微乳液萃取钍过程同时具有热力学稳定性和高效快速等优点。A stable microemulsion system is constructed by choosing α-aminophosphonate extractant Cextrant 230 and an anionic surfactant sodium bis(2-ethylhexyl)sulfosuccinate(AOT)as the cosurfactants. The effects of some factors such as pH and the concentration of Cextrant 230,AOT,NaOH and the sulfate in the aqueous solution on the maximum water ratio(x0)are studied. The process and effects of microemulsion formation are analyzed and the optimized conditions for the stable microemulsion are determined. The Cextrant 230-AOT-n-heptane microemulsion system is applied for the extraction of thorium. The effects of emulsion-to-water volume ratios,the concentrations of Cextrant 230,AOT and sulfate,temperature are studied. The extraction rate of thorium in the microemulsion system increases with the increase of the concentration of Cextrant 230(or AOT),which is significantly higher than that of AOT-n-heptane microemulsion system. Cextrant 230 and AOT have a synergistic effect on the extraction of thorium. Temperature has little effect on extraction of thorium and the reaction is entropy-driven. Upon the comparison of the stripping of thorium by different inorganic acids,sulfuric acid is chosen as the stripping reagent. The loading capacity for ThO2is about 1. 43 g/L. This microemulsion system is applied to the separation of Th from the actual bastnaesite sulfate leach liquid after the cerium extraction and the thorium content can be reduced to less than 0. 1 mg/L. The microemulsion system has both the advantages of thermodynamic stability and high efficiency.

关 键 词：α-氨基膦酸酯萃取剂 反相胶团 萃取 钍 

分 类 号：O658.2[理学—分析化学]