Effect additional pH on separation extraction gadolinium from terbium and europium with Di-2-(ethylhexcyl)phosphate acid

Abstract Rare earth elements are strategic materials, difficult to obtain, and have wide uses. Currently, it is still difficult to separate and refine REE’s because it has similar physical and chemical properties. Solvent extraction is most successful method used for the separation of REE’s. Di-2-ethylhexyl phosphoric acid has been widely used in industry for the separation and of REE’s. Purpose of this study is effect of pH on basic parameters extraction which include distribution coefficient, extraction efficiency and separation factor in extraction gadolinium, terbium and europium through complex with D2EHPA. Determination effect pH is a parameter determined in process extracting standard solutions gadolinium, terbium and europium using D2EHPA with n hexane. Basic parameters in extraction gadolinium, terbium and europium with D2EHPA at pH 4 are as follows KdGd = 89.90; αGd/Tb = 5.63, Gd/Eu = 1.83; %E = 98.90. KdTb = 15.94; αTb/Gd = 0.17; Tb/Eu = 0.32; % E = 94.10; KdEu = 1.40; αEu/Gd = 0.01, Eu/Tb = 0.08; %E = 98.29. From these valuesit can be concluded that gadolinium, can be separated from terbium and europium by the solvent extraction method by forming complex D2EHPA with best separation results obtained at pH 4.