Ion-exchange equilibria with quaternary ammonium ions

Abstract

Variation of the quaternary ammonium ion (Q) selectivity, for the series NMe₄, NEt₄, NPr₄, and NBu₄ ions, with the NH₄ reference ion is found to be similar to that with the H ion. Resin preference for the Q ion is found to decrease with change in reference ion in the order Li > H > Na > NH₄ > K. The effect of cross-linking upon the NEt₄–NH₄ system is compared to that with the H reference ion. Comparison of the equilibrium curves on one resin, for these two systems, at 25 and 80° has been made and these, and the above trends, are discussed in the light of modern theory of selectivity.