摘要
为了将粉煤灰浸出液中稀土元素钇萃取分离出来,利用协同萃取体系对粉煤灰浸出液进行研究。本文先以纯的氧化钇浸出液为研究对象,用2种萃取剂二磷酸酯(2-乙基己基)(P204)、2-乙基己基磷酸单2-乙基己基酯(P507)协同萃取单一稀土元素氧化钇浸出液中的钇,探究萃取钇过程中的最优参数。结果表明,在2种萃取剂P204和P507体积比为3∶7,2种萃取剂总体积分数10%,油水比(O/A=1.33),接触时间为30 min,溶液pH为1.4,温度25℃的条件下,钇萃取率可达到89%,协同萃取系数R最大值为1.7,表明2种萃取剂在此条件下对钇的萃取有很好的正协同作用。在上述实验基础上,将最优条件适用于粉煤灰浸出液中钇的萃取,结果发现,在协同萃取体系下钇(Y)与镧(La)、铈(Ce)、镨(Pr)、钕(Nd)的分离系数βY,La,βY,Ce,βY,Pr,βY,Nd分别为222.82,142.82,146.97,119.81,均高于P204和P507单一萃取体系下的分离系数,表明协同萃取体系可以将钇与其他几种稀土元素很好地分离,为工业生产中分离稀土元素提供理论指导。利用恒摩尔法和斜率法,推测出P204与P507协同萃取稀土元素钇的萃合物结构,并确定其萃取机理方程式。
To extract and separate the rare earth element of yttrium from the coal fly ash leaching liquid,the synergistic extraction system was used to study the coal fly ash leaching liquid.In this paper,the pure yttrium oxide leaching solution was taken as the research object.To explore the optimal parameters in the extraction process,two extractants di-2-ethylhexyl phosphonic acid(P204)and 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester(P507)were used to the synergistic extraction of yttrium in the single rare earth element yttrium oxide leaching solution.Results found that when the volume ratio of two kinds of extractant P204∶P507 was 3∶7,extraction total volume concentration was 10%vol.,oil-water ratio was 1.33(O/A=1.33),the contact time was 30 minutes,solution pH was 1.4,the temperature was 25℃,yttrium extraction efficiency can reach 89%,the maximum value of synergistic extraction coefficient R was 1.7,which showed that two kinds of extractant had good positive synergistic effects.Based on the above experiments,the optimal conditions were applied to the extraction of yttrium from coal fly ash leaching liquid.The results showed that the yttrium(Y)and lanthanum(La),cerium(Ce),praseodymium(Pr),neodymium(Nd)separation factorβY,La,βY,Ce,βY,Pr,βY,Nd coefficient were 222.82,142.82,146.97,119.81 under the synergistic extraction system,which were higher than separation factor of P204,P507 single extraction system.It showed that synergistic extraction system could separate yttrium from other rare earth elements and provide theoretical guidance for industrial separation of rare earth elements.By using the constant molar method and slope method,the structure of the complex of P204 and P507 synergistic extraction of rare earth element yttrium was inferred,and the extraction mechanism equation was determined.
作者
吉万顺
周长春
潘金禾
曹闪闪
汤梦成
胡婷婷
JI Wanshun;ZHOU Changchun;PAN Jinhe;CAO Shanshan;TANG Mengcheng;HU Tingting(School of Chemical Engineering and Technology,China University of Mining and Technology,Xuzhou 221116,Jiangsu,China;Key Laboratory of Coal Processing and Efficient Utilization,Xuzhou 221116,Jiangsu,China)
出处
《河南理工大学学报（自然科学版）》
CAS
北大核心
2020年第2期62-68,共7页
Journal of Henan Polytechnic University（Natural Science）
基金
国家重点基础研究发展计划(973)项目(2014CB238905)
关键词
钇
萃取剂
协同萃取
粉煤灰浸出液
萃取机理
yttrium
extractnt
synergistic extraction
leaching of coal fly ash
mechanism of extraction process
