Anion-exchange Studies. IV. Nature of the Adsorbed Species in the System Co(II)-HCl1

The spectra of Co(II) solutions in the presence of LiCl, HCl, and HClO/ sub 4/ have been re-examined in the region from 325 to 650 m mu . The optical absorbancy data have been correlated with the known adsorption behavior of Co(II) on strong-base quaternary ammonium) anionexchange resins, and the principal species adsorbed on the resin is shown to be the neutral complex CoC/sub 2/.aq. The equilibrium constant for the reaction Co/sup ++/.aq + 2Cl/sup -/ in equilibrium -CoCl/sub 2/-aq is calculatedto be 5 3 x 10/sup -2/ F/sup -2/ These data appear to support the suggestion that at least two distinct anion adsorption processes may occur in transition metal ion retentions. (auth)