Figure 2: The plot of distribution coefficient (log Dí) against pH at the extraction of Cu(I) with lauric acid (0.5 M) in benzene at 298.2 K. Initial concentration of Cu(I) (M): (?) 5◊10-4; (?) 2.5◊10-3; (?) 5◊10-3; (?) 2.5◊10-3.