容量法直接测定稀土萃取分离工艺负载有机相中稀土浓度

Direct Titration of Rare Earths in Organic Phase from Extraction Separation Technology

在乙醇存在下,以偶氮胂Ⅲ为指示剂,乙二胺、磺基水杨酸为掩蔽剂,EDTA容量法直接测定稀土萃取分离工艺负载有机相中稀土浓度。省去了有机相的反萃取分离过程,提高了测定的准确度。对不同浓度的稀土有机相样品进行测定,其相对标准偏差(n=5)在1.00—0.29％范围。方法适合于环烷酸体系萃取分离稀土元素工艺各级水相、有机相中稀土浓度的直接测定。

In the presence of ethyl alcohol,the content of rare earths(RE)in the organic phase of extraction obtained from the separation technology is directly titrated with EDTA,using arsenazoⅢas indicator and ethylenediamine and sulfosalicylic acid as masking agents.No preliminary reverse extraction of REfrom the organic phase is required in the procedure .The RSD_s(n=5)range from 0.29-1.11%for samples of different RE contents.