络合剂H_3cit对P_(204)-RECl_3-LA体系萃取镨钕的影响

以二-(2-乙基己基)磷酸(P204)为萃取剂,在含有乳酸的稀土氯化物(PrCl3或NdCl3)溶液中添加一定比例的络合剂柠檬酸,研究了在pH=3条件下络合剂柠檬酸含量对P204-RECl3-LA体系萃取镨钕的分配比、分离系数及萃取容量的影响.结果表明:含有柠檬酸的乳酸体系萃取镨钕的分配比、分离系数及萃取容量明显高于单一乳酸体系,分离系数由原来的1.44提高到1.68,萃取容量由原来的25.23 g/L提高到28.53 g/L.这为研究非皂化萃取体系中稀土的绿色清洁萃取方法提供了理论依据和技术基础.

Effect of Complexing Agent Citric Acid on Extraction Pr/Nd in P204-RECl3-LA System

The effect of the content of citric acid on distribution ratio,separation coefficient and extraction capacity of Pr/Nd in the P204-RECl3-LA system was investigated.The di-(2-ethyl hexyl) phosphoric acid(P204) was used as an extraction solvent and a certain proportion of citric acid was added into the rare earth chloride(PrCl3 or NdCl3) solution in the presence of lactic acid.The results showed that the distribution ratio,separation coefficient and extraction capacity of Pr/Nd in the P204-RECl3-LA system containing citric acid are significantly higher than that of a single lactic acid system.The separation factor increases from 1.44 to 1.68 and the extraction capacity increases from 25.23 g/L to 28.53 g/L,which provides a theoretical and technical basis for the study of green cleaning extraction method of rare earth in the non-saponification extraction system.