Figure 1: The plot of distribution coefficient (log Dí) against pH at the extraction of Cu (I) with lauric acid (0.2 M) diluted in benzene at 298.2 K. Initial concentration of Cu(I) (M): (?) 5◊10-4; (?) 2.5◊10-3; (?) 5◊10-3; (?) 2.5◊10-2.