Extraction of Uranium(VI) from Nitric Acid Solution Using Pyrrolidone Derivatives

Abstract

The extraction behavior of uranyl species from HNO 3 aqueous solutions using CH 2 Cl 2 containing pyrrolidone derivatives as extractants has been studied to find an alternative to tributyl phosphate as an extractant. In this study, we used N-cyclohexyl-2-pyrrolidone (NCP), N-octyl-2-pyrrolidone (NOP), and N-dodecyl-2-pyrrolidone (NDP) as the extractants. As a result, it was found that NCP, NOP, and NDP (abbreviated as NRP) extract U(VI) as UO 2 (NO 3 ) 2 (NRP) 2 , that a part of NCP in CH 2 Cl 2 phase is moved to the aqueous phase, and that the extractability (corresponding distribution ratio) of U(VI) increases with increasing [HNO 3 ] int from 7% (0.08) (½HNO 3 int ¼ 0:1 M, ½NRP int ¼ 1:0 M) to more than 90% (11) (½HNO 3 int ¼ 3:0 M, ½NRP int ¼ 1:0 M). From these results, it is expected that NOP and NDP extract U(VI) effectively from HNO 3 solution of more than 3 M and that the extracted U(VI) species are stripped by using HNO 3 aqueous solution of low concentration.

Separation of Uranium(VI) and Vanadium(V) from Sulfuric Acid Media by Amine Based Extractants through Liquid-liquid Extraction Technique#

“…The extraction behavior of new bi-functional ligands containing sulfur and amide groups towards the U(VI) ion from nitric acid was studied and reported [19][20][21][22][23][24] . Other reports are related to P based extractants used for U extraction [25][26][27][28][29] and our previous extraction studies on U extraction was developed and reported [30][31][32][33] .…”