Experimental data on the solvate extraction of cerium(III) and yttrium(III) by solutions of oleic and naphthenic acids in o-dimethylbenzene were obtained. After mathematical analysis of the dependences of the distribution coefficient on pH and the composition of the organic and aqueous phases, the structure and composition of the solvate complexes were determined, as well as the values of Gibbs free energies and equilibrium constants of the reaction.
Data on the extraction of cerium(III) and yttrium(III) by naphthenic acid solution in o-xylene from chloride media were obtained. The experiment showed W-shaped dependence of the distribution coefficient of cerium(III) and yttrium(III) on the Cl content in the equilibrium aqueous phase. The minima of the dependence are explained by the formation of non-extractable complexes MeCl 2 +and MeOH 2 +, the maxima - by the increase in the degree of dissociation of naphthenic acid and the increase in the ionic strength of the solution.
The purpose of this research is to develop a new method of extraction and separation of rare earth metals, which will be effective in hydrometallurgical processes, i.e. in the processing of eudialyte concentrate. The task of the research is the experimental determination of distribution and separation coefficients in solvent extraction of rare earth metals from aqueous solutions with organic extractants, as well as the calculation of the extraction mechanism and thermodynamic constants on the basis of experimental data.
