Frequency response of continuous-flow adsorber for multicomponent system

In this paper, we present a theoretical analysis of the frequency response of a continuous-flow adsorber with periodic modulation of the inlet flow-rate to measure multicomponent diffusion kinetics in porous media. Micropore diffusion kinetics is assumed for the intraparticle mass transfer mechanism and three different shapes of microparticle are considered: slab, cylinder, and sphere. Simulation results for a binary system show that the frequency response of the faster diffusing component is strongly influenced by the slower component. The out-of-phase characteristic function of the frequency response of the faster diffusing component shows maximum and minimum points. The deviation between these maximum and minimum values becomes smaller when the cross-terms of diffusivity go to zero, while the deviation becomes larger when the cross-terms of the adsorption equilibrium constant go to zero. Contrary to the behaviour of the out-of-phase function of the faster diffusing component, the out-of-phase function of the slower diffusing component shows no extrema at all. The in-phase characteristic function of the frequency response of the continuous-flow adsorber is not affected by the overflow parameter.