Phase Diagrams of Ternary and Quaternary Systems

A special case of great industrial relevance is the examination of reciprocal salt pairs representing a quaternary system of two salts that do not share a common ion 

and BY. Shown are the construction of grid lines and scales. As scale the amount of the particular ions is used. All mixtures of AX and BY lie on the diagonal line connecting corners AX and BY. The same applies to mixtures of BX and AY. (The water content is excluded for simplification purposes.) 

Much more information regarding the construction of ternary and quaternary phase diagrams and also other possibilities of their representation can be obtained from the monographs [1,2]. Also, Refs [3,4] should be recommended as excellent source of fundamental knowledge on heterogeneous phase equilibria. 

In Sections 3.3.7 and 3.3.8 with the cases of enantiomers and the reciprocal conversion, examples of ternary and quaternary solution equilibria of industrial importance will be discussed. 

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