中文摘要：

针对高酸度下P204（DEHPA）萃取剂萃取轻稀土氯化物时,La^3＋、Ce^3＋、Pr^3＋、Nd^3＋之间分离系数较低的问题,本文研究了含有柠檬酸（H3cit）的P204-HCl体系中,料液酸度与柠檬酸浓度对轻稀土分离系数的影响,并与P204-HCl体系的萃取结果进行了比较。实验结果表明：在P204-HCl-H3cit体系中,轻稀土分离系数随酸度的增大而降低,随柠檬酸浓度的增加而提高。当料液酸度pH=1.0、柠檬酸浓度=0.25 mol/L时,Ce/La、Pr/Ce和Nd/Pr的最大分离系数分别为4.10、1.71和1.54,均高于P204-HCl体系下的最大分离系数。

英文摘要：

The separation coefficient of light rare earth was lower in P204 （DEHPA）- HCl system at high acidity. Pointing to this problem, in this paper , the effects of the feed acidity and citric acid（H3 cit） concentration on the separation coefficient of light RE was investigated in P204 -HCl-H3 cit system compared with P204 -HCl system. The extraction mechanism was studied by FT-IR spectra. The result showed that the separation coefficient reduced with the increase of the feed acidity, and increased with the increase of citric acid concentration in P204 -HCl-H3 cit system. When feed acidity pH=1. 0 and citric acid concentration was 0.25 mol L^-1, the maximum separation coefficient were βCe/La=4.10, βPr/Ce =1.71 and βNd/Pr=1. 54, respectively, and which was bigger than that in HCl system.