Effect of polar molecular organic solvents on non-aqueous solvent extraction of rare-earth elements

The extraction and separation of five different rare-earth elements, La, Nd, Eu, Dy Yb, from an aqueous chloride solution non-aqueous solutions using the solvating extractant Cyanex 923 was investigated. As previous studies had demonstrated potential solvent (NASX) to refine rare earths ethylene glycol, structural analogues glycol (1,2-propanediol 1,3-propanediol) other polar organic solvents (triethylene dimethylsulfoxide, methanol, N,N-dimethylformamide N,N-dimethylacetamide) were studied. data interpreted in terms properties: dielectric constant, Gutmann donor number, molecular structure hydrogen-bonding capabilities. Remarkable differences observed between behaviour 1,2-propanediol 1,3-propanediol. Therefore, these systems further studied elucidate speciation elements by optical absorption luminescence spectroscopy. Based on studies, both contact-ion-pair formation solvation strength are assumed play important role solvents. can be exploited fine-tune earths.