抄録
Recently, a new liquid membrane separation process called ESPLIM (Electrostatic Pseudo-Liquid Membrane) was proposed. This process is characterized by the simultaneous extraction and stripping in a single tank, in which the aqueous phase is dispersed in the organic phase under a high electrostatic field. To obtain a fundamental knowledge of the applicability of ESPLIM to recover metal values from the leach solution, it is useful to study the characteristics of extraction and stripping, separately. In this study, the effect of various factors on the extraction of Ni(II) with di(2-ethylhexyl)phosphoric acid from NiSO4–CH3COONa aqueous solution and the stripping of the extracted Ni(II) with HCl aqueous solution was investigated separately under a high electrostatic field. The main results are as follows. The dispersion of aqueous solution is improved greatly by an increase in electrostatic voltage. At the same voltage, NiSO4–CH3COONa solution disperses better than HCl solution. The dispersion of aqueous solution is depressed by an increase in the concentration of Ni(II) loaded in the organic phase. The extraction rate is fairly independent of the degree of dispersion of feed solution which is induced by voltage, while the stripping rate increases remarkably with an increase in the degree of dispersion of stripping solution.
