Application of composite materials based on various extractants for isolation of lanthanide(III) nitrates from multicomponent aqueous solutions

Extraction of lanthanide(III) nitrates of eerie subgroup was studied by pur e tributylphosphate, 50% solution of trialkylmethylammonium nitrate in tolu ene and composite materials based on porous Teflon and mentioned extractans in the presence of 1-5 mol/dm(3) of sodium nitrate in aqueous phase. Effec t of additions of sodium sulfate and chloride to nitrate solutions on distr ibution parameters of lanthanides(III) was determined. The extraction proce ss can be described with taking into account the formation of [Ln(NO3)(3)(S )(j)] (j=3, 4) in organic phase. The extraction constants were estimated. I t was established, that accounting tributylphosphate concentration in the p hase of composite, extraction constants and isotherm shape for systems base d on tributylphosphate are identical within the error of determination. In the case of trialkylmethylammonium nitrate those for composite are little g reater then for liquid extractant.