Ferrocyanide molybdate, a new inorganic ion exchanger-II Ion exchange and radiochemical properties

Capacity determinations on ferrocyanide molybdate indicate a maximum value of 3·9 m-equiv/g. The more hydrated the cation is the more difficult it becomes to saturate the exchanger and the flatter the isotherm. The alkali metal-hydrogen ion selectivity coefficients, when plotted semilogarithmically as a function of exchanger composition, indicate a continuous range of solid composition, and Barrer's theoretical treatment has been applied to the results. The affinity series for the alkali metals is Na < K < Rb < H < Cs. Investigations on the exchange equilibria of bi-mono and tri-mono valent exchanges shows that Cs is preferred to all other ions studied. The very high affinity of FeMo for Cs is explained in terms of a chemical reaction taking place between the almost unhydrated Cs and the layered lattice of FeMo.