In this paper, we present a theoretical analysis of the frequency response
of a continuous-flow adsorber with periodic modulation of the inter flow-ra
te 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 frequenc
y 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 wh
en the cross-terms of diffusivity go to zero, while the deviation becomes l
arger when the cross-terms of the adsorption equilibrium constant go to zer
o. Contrary to the behaviour of the out-of-phase function of the faster dif
fusing component, the out-of-phase function of the slower diffusing compone
nt shows no extrema at all. The in-phase characteristic function of the fre
quency response of the continuous-flow adsorber is not affected by the over
flow parameter.