Diffusion time in core–shell packing materials

The recently developed pellicular packing materials show high efficiency and have attracted great interest. The improved mass-transfer kinetics of the core–shell particles is due to the shorter diffusion path of the molecules within the stationarity phase. In this study we show how the diffusion time of the molecules visiting the stationary phase depends on the geometry of the porous shell stationary phase. The mean escape time of diffusion is calculated on the basis of a random walk model.