The Ion Exchange Process

Abstract

It has become so customary to associate the term ‘ion exchange’ with the standard technique of causing water to flow through columns of resin, that it tends to be forgotten that the principle of the process itself is neither new, nor unduly complex. It has probably been used by every living chemist in the earliest stages of his studies. The experiment of detecting chloride in solution, by the addition of silver nitrate solution, typifies the commonest type of ion exchange reaction:

$${\text{Na}}^{\text{ + }} {\text{C1}}^{\text{ - }} {\text{ + Ag}}^{\text{ + }} {\text{NO}}_{{\text{3}}^{\text{ - }} } {\text{ = N}}_{{\text{a}}^{\text{ + }} } {\text{NO}}_{{\text{3}}^{\text{ - }} } {\text{ + Ag}}^{\text{ + }} {\text{C1}}^{\text{ - }} \downarrow...$$