A method for the determination of extraction capacity and its application to -tetraalkylderivatives of diglycolamide-monoamide/n-dodecane media

Sasaki, Yuji  ; Sugo, Yumi; Suzuki, Shinichi; Kimura, Takaumi 

The detailed study of extraction capacity of diglycolamide (DGA) with and without DHOA, N,N'-dihexyloctanamide as a modifier, was performed by using the novel analytical method for the determination of the limit of metal concentration in the organic phase (LOC). The effect on modifier was studied and it is confirmed that LOC increases with DHOA concentration. It is noteworthy that LOC reaches to the stoichiometric value, which is obtained by the extraction reaction, by using 0.1M TODGA mixed with more than 0.5M DHOA into n-dodecane. Without modifier, relation of the different DGA compounds with LOC was investigated, and it is clear that LOC using N,N,N',N'-tetradodecyl-diglycolamide (TDdDGA), whose extractant can suppress the third phase, reaches to the stoichiometric value. From this work, it is obvious that the application of the condition without the third phase formation, e.g., enough concentration of modifier coexisted and DGA with long alkyl chain, is important to attain the stochiometric LOC value.