（毕业设计论文）《Cyanex923Ce、F性能研究》.doc

PAGE 1 精品 摘 要 协同萃取就是在两种或两种以上萃取剂组成的多元素萃取体系中，金属离子的萃取分配比D协显著大于每一萃取剂在相同条件下单独使用时的分配比之和D加合，即认为这一萃取体系有协同效应。与此相反，若D协小于D加合则为反协同，如两值相等，则无协同。本文主要研究了中性萃取剂三烷基氧膦（Cyanex 923）与酸性膦酸萃取剂二（2,4,4-三甲基）膦酸（P204）协同萃取Ce和F的性能。具体内容如下： （1）考察了Cyanex923与P204单独体系对Ce(IV)、Ce(III)、F(I)及Ce(IV)-F混液的萃取。确定体系中各离子是否可被Cyanex923和P204萃取。 （2）研究了 Cyanex 923 与P204混合体系对Ce(IV)、F(I)、Ce(III)及Ce(IV)-F混液的协同萃取性能。确定该混合体系各离子是否存在协同萃取效应。计算了萃取Ce(IV)的协同增长因子。用斜率法确定了Cyanex 923与P204确定两种萃取剂有最大协萃效应时的分配比，并探讨萃取机理。 （3）考察了温度对Cyanex923与P204混合体系萃取Ce(IV)的影响，计算Ce(IV)萃取的热力学常数。 关键词： Cyanex923，协同萃取，Ce，F Researh on the characters of cerium and fluorine synergistic extraction with Cyanex923 and organophosphoric acids extractant Guo Hongfei Class 0602, Environmental Science, School of Environmental and Biological Engineering, Liaoning Shihua University, Liaoning Fushun,113001 Abstract Synergistic extraction means that the extraction distribution ratio Dsynergistic in the multielement systems composed by two or more extractant is much more than that of Dadduct with single extractant using in the same condition. Namely the extractant system is regarded to have synergistic effect. On the contrary, the system was regard to have anti- synergistic effect, if Dsynergistic is smaller that Dadduct and no synergistic effect when they are equal. The synergistic extraction of Ce and F with a neutral extractant named three alkylated phosphine oxide (Cyanex923) and a kind of organophosphoric acid extractant named bi-(2, 4, 4- trimethyl) phosphinic acid (P204) has been investigated. The following aspects were included in the thesis: (1) The extraction of Ce(IV), Ce(III), F(I) and Ce(IV)-F mixed solution with Cyanex923 and P204 alone was studied to determine whether the ions could be extracted by Cyanex923 and P204 or not. (2) The synergistic characters of Ce(IV), Ce(III), F(I) and Ce(IV)-F mixed solution with mixture of Cyanex 923 and P204 was investigated to make sure the ions with synergistic extraction. The synergistic increasing factors were calc