The effect of diluents on the extraction of Sm(III) using N,N,N',N'-tetrabutylmalonamide

Abstract

A study has been made of the extraction of samarium(III) from nitrate solutions using N,N,N',N'-tetrabutylmalonamide (TBMA) in a series of diluents. The dependence of the extraction distribution on the concentrations of aqueous nitric acid, lithium nitrate and organic TBMA was investigated. The experimental results showed that the extraction efficiency of TMBA in different diluents for Sm(III) increases in the order: chloroform, carbon tetrachloride, benzene, xylene, toluene, cyclohexane, n-hexane, n-octane. The stoichiometry of the extracted species conform to Sm(NO3)3·3TBMA in all the employed diluents. The interaction between extractant or extracted species and diluent is discussed and a quantitative expression relating the extraction constant and the parameters of the diluent has been established.