Application of ion exchange for deep purification of substances

Consideration is being given to two groups of problems, which can be solved with application of ion exchange: purification of nonelectrolytes or weak electrolytes from strong electrolyte impurities; electrolyte purification from electrolyte impurities. Problems of the first groups (water demineralization, freon composition) purification, purification of liquid-crystal substances etc.) can be solved by properly selected ionite ion substitution for impurity ions. The process may be conducted both on columns with stationary ionite layer and during phase counter flow. It is advisible to solve the problems of the second group, especially when purifying large amounts of substance, using counter flow columns. Schemes of the processes, principles of selecting conditions of their procedure, problems of implementation are considered. Typical examples (cesium purification from rubidium, yttrium purification from rare earths and others) are presented