Studies of the hydrous titanium oxide ion exchanger, 3

In order to understand the cation-exchange behavior of hydrous titanium oxide, the distribution coefficients of various cations were measured as a function of the pH and the ionic strength. The order of selectivity for alkali metal ions is Cs+>Pb+>K+>Na+, for alkaline earth metal ions, Ba2+>Sr2+>Ca2+, and for bivalent transition metal ions, Zn2+>Cu2+>Co2+. From the dependency of the distribution coefficients on the pH, it is concluded that the apparent dissociation constants of the exchanger reported previously are not constant, but gradually decrease with the pH of the medium. By using ammonium chloride and ammonium nitrate solutions as eluents, nearly quantitative separations of 137Cs-133Ba and 137Cs-89Sr were achieved with a relatively small column. (auth.)