Extraction of uranium with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (PC-88A)

The extraction behavior of uranium (VI) from chloride medium with 2-ethylhe xyl phosphonic acid mono-2-ethylhexyl ester (PC-88A) in dodecane has been i nvestigated under wide range of conditions. Attempts have been made to esta blish the extraction mechanism of uranium(VI) with PC-88A. Treatment of the distribution data by slope analysis technique showed the formation of a mo nomeric complex of the nature [UO2(A(2)H)(2)]. Formation of this species wa s also confirmed by non-linear least square regression of the distribution data to the mathematical expression correlating percentage extraction and a cidity. In this investigation attempts have also been made to develop a mat hematical model for the system (UO2Cl2-HCl-H2O-PC-88A-dodecane) using exper imental data on the distribution of uranium against initial aqueous acidity at different initial metal concentration. The mathematical model D = 37.54 7+/-0.223/C(i)(1/2)x[H-i](2) can be used to predict the concentration of ur anium in organic as well as in aqueous phases at any initial concentration of uranium [C-i] and initial hydrogen ion concentration [H-i]. The extracti on constant (K-ex) has been calculated.