Two unified equations for the thermodynamics and kinetics of chromatographic processes

As a core technique in the field of analytical chemistry, chromatography has been widely applied in chemistry, biology, medicine, and numerous other disciplines. To address the fragmentation challenge in traditional chromatographic theory, this paper systematically presents two unified equations for chromatographic thermodynamics and chromatographic kinetics based on prior research. In 1990, based on the unified equation of chromatographic retention values using statistical thermodynamics and lattice models, we broke through the barriers of retention value formulas across multiple chromatographic modes, predicted the retention behavior of various types of chromatography (gas-solid chromatography, gas-liquid chromatography, liquid-solid chromatography, supercritical fluid chromatography, etc.) through molecular parameters, verified the high prediction accuracy through experiments, which provided theoretical support for the conversion of retention values for different modes. In 2020, we established a unified equation for the height of liquid chromatography trays, which extended the study of chromatographic kinetics from one-dimensional space to three-dimensional space, by introducing the heat conduction equation and integrating the contributions of radial diffusion and thermal effects to the tray height equation, we achieved a unified description of column efficiency rules for multiple chromatographic modes such as high-performance liquid chromatography (HPLC), ultra-high performance liquid chromatography (UPLC), capillary electrochromatography (CEC), and clarified the conditions for achieving high efficiency in high-speed chromatography. This study will integrate the dispersion theory of multiple chromatographic modes such as gas chromatography (GC), liquid chromatography (LC), and supercritical fluid chromatography (FSC) to reveal the common physical and chemical essence of different chromatographic techniques, achieving a theoretical leap from macroscopic description to microscopic mechanism. On the one hand, it provides quantitative theoretical support for optimizing chromatographic conditions, transferring methods, and developing new separation technologies, clarifying the conditions for achieving high-speed and efficient separation. On the other hand, simplifying the knowledge system of chromatographic analysis courses, reducing the burden of teaching and learning, providing scientific basis for teaching reform, and helping students establish a systematic chromatographic knowledge framework. The two unified equations respectively address the thermodynamic essence of "whether separation is feasible"and the kinetic key of "how to achieve efficient separation", realizing a leap forward in the systematization of chromatographic theories. This study clarifies the core values of the unified theories in academic integration, technological optimization, and teaching reform, and prospects their development directions in integration with artificial intelligence and the exploration of new separation technologies, thus offering an important theoretical reference for the advancement of chromatography as a discipline.