On film mass transfer coefficient expression in ion-exchange chromatography systems

The mass transport of a charged analyte in ion-exchange mode from the flowing fluid stream in the channels for bulk flow in a packed bed of charged particles (or in the throughpores for bulk flow of a monolith) to the surface of the charged particles (or to the charged surfaces of the throughpores of a monolith) occurs by the mechanisms of convection, diffusion, and electrophoretic migration, and the theoretical expression for the film mass transfer coefficient, K-f, of a charged analyte involves parameters that have to be determined from experimental data. In this work, the type of chromatographic ion-exchange experiments and the data that have to be measured in the experiments together with two different methods for calculating the experimental values of the film mass transfer coefficient, Kf, as well as a procedure for determining the parameters of the theoretical expression for Kf are presented. (C) 2007 Elsevier B.V. All rights reserved.