Effect of temperature variations on non-equilibrium and non-isothermal two-component liquid chromatography in cylindrical columns

Abstract

The effect of temperature variations in liquid chromatographic columns of cylindrical geometry are studied by formulating a non-isothermal and non-equilibrium two-dimensional (2D) lumped kinetic model (LKM) simulating the flows of two-component mixtures. The developed models contain systems of coupled convection-dominated partial differential, differential, and algebraic equations for mass and energy balances in the mobile and stationary phases. For linearized isotherms, semi-analytical solutions are obtained by utilizing a sequential application of finite Hankel and Laplace transformations along with Tschirnhaus-Vieta and eigen-decomposition techniques. Temporal moments are also generated numerically from the derived semi-analytical solutions for a deeper understanding of the process execution. For nonlinear isotherms, a high-resolution finite volume scheme (HR-FVS) is employed to numerically simulate the model equations and also utilized to benchmark the precision scopes of derived semi-analytical solutions. A few case studies of linear and nonlinear chromatography are conducted. The connectivity of thermal waves with the concentration peaks is examined via numerical simulations and essential model parameters that affect the chromatographic column performance are identified. The results of this study will be very useful for optimizing and improving the non-isothermal and non-equilibrium liquid chromatography involving two-component mixtures and cylindrical-shaped columns.