Articles techniques et présentations

The exact moment approach (EMA) is adopted to predict, without any fitting parameters, the plate height curves for polystyrene microparticles of different sizes in micropillar array columns performed by hydrodynamic chromatography. The EMA allows us to decouple the contribution of horizontal and vertical dispersion terms and thus investigate the influence of pillar height and interpillar distance on separation performance. The Comsol tool, implementing the EMA equations, developed for micropillar array columns can be easily extended and generalized to any geometry representing the unit-periodic cell, the repetition of which allows the entire chromatographic column to be reproduced/modeled. Stationary-coupled equations for the particle pdf and the b-field, implemented as PDE coefficient form with periodic boundary conditions, can be efficiently solved together with the incompressible velocity field in creeping-flow conditions. From their solution, the effective velocity vector and the dispersion tensor can be estimated in a straightforward way.