The understanding of the three-dimensional graphical behavior of the L-L-S phase equilibrium as a valuable tool to avoid spurious or incoherent experimental data

Abstract

The complexity and variety of possible behaviors of the quaternary liquid-liquid, liquid-liquid-solid equilibrium at constant temperature are very high and, sometimes, are not well understood. It is not difficult to find references in literature where important misinterpretations and mistakes are committed as a consequence of applying a non-adequate experimental methodology and a lack of the spatial point of view. Thus, the objective of the present paper is to show several examples where special behaviors are selected to clarify some aspects concerning the experimental determination and graphical representation of liquid-liquid-solid equilibrium data, and emphasize the importance of the knowledge and consideration of the qualitative expected behavior of the system under study, obtained from the binaries.