ABSTRACT
The different forms of chromatography are determined by the differences in physical state of the mobile phase. These include gas chromatography, supercritical fluid chromatography, and liquid chromatography. Adjusting the temperature and pressure can change the mobile phase from liquid to supercritical fluid to gas, with concomitant changes in their physical properties. The physical properties of the mobile phase affect the flow characteristics, column efficiency (kinetics), and retention (thermodynamics) in the chromatographic process. The diffusivities of solutes in the mobile phase determine the selection of column dimensions to obtain the desired column efficiency in reasonable time. When using packed columns, the column parameters that influence diffusion and separation efficiency are the size and surface structures of the packed particles. The chapter describes the characteristics of solvating gas chromatography and illustrates some resultant experimental results.
