In this contribution, we review the recent literature relating to the measurement and modelling of all diffusion-dominated processes contributing to the efficiency of a chromatographic column. In first instance, this involves the measurement and modelling of the overall effective diffusion coefficient Deff (determining the so-called B-term band broadening). The latter manifests itself most clearly during a so-called peak parking experiment. Using effective medium theory modelling, the measured Deff-value can subsequently be decomposed into its constituent contributions, of which the intra-particle or the mesoporous zone and the surface diffusion coefficient are the most important ones. As an accurate estimation of the diffusion processes also allows computing the C-term plate height contribution terms, the review ends with some recent insights obtained when using the established B- and C-term contributions to compute the degree of eddy-dispersion in contemporary packed bed columns.
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