ION EXCHANGE IN FUSED SALTS. II. THE DISTRIBUTION OF ALKALI METAL AND ALKALINE EARTH IONS BETWEEN CHABAZITE AND FUSED LINO3, NANO3, AND KNO3,

A study was made of the ion-exchange distributions of Na, Ca, K, Ba, Rb, and Cs between the mineral exchanger chabazite and each of the fused salts LiNO3, NaNO3, and KNO3. The distribution coefficients and the selectivity sequences of the ions varied from salt to salt. The selectivity sequency obtained in fused LiNO3 was taken as the normal one and was in the order of increasing ionic radii of the respective periodic groups. In general the sequence was related to a size-charge effect, and transpositions in this sequence observed in fused NaNO3 and KNO3 were explained by the influence of the sieving properties of chabazite in depressing the distribution coefficients. In each melt a relationship was found that depended on the size of the chabazite channels, and the operation of a two-way traffic mechanism for ion exchange. In these experiments ion charge was less important than ion size in determining selectivity order. Author