The extraction reaction and separation in most cases occur on liquid-liquid interface

and generally

the formation of a new phase and phase-separation kinetics in extraction systems depend on step-by-step evolution of molecular aggregates in solution microstructure. Therefore

the research on various intermolecular interaction appeared in solutions or on the interface of contacting liquid phases during extraction and separation process

and exploration about the influence from the change

interrelationship and synergistic effect of those intermolecular interactions are becoming one of the research focuses and frontier around the world in current separation sciences and chemical engineering. It is very important towards understanding the microscopic mechanism in the separation process

and also how to control the separation selectivity. In present paper

recent research progress and some typical works about the intermolecular interaction on the interfaces of liquid phases

and various experimental techniques and methods employed to describe the intermolecular weak interaction in extraction and separation systems are reviewed.