DYNAMIC TRANSPORT OF MULTICOMPONENT MIXTURES OF GASES IN POROUS SOLIDS

Dynamics of transport of ternary mixtures of non-adsorbable gases (hydrogen, helium, nitrogen, argon) through porous solids was studied experimentally in the dynamic version of the Wicke-Kallenbach diffusion cell. Four samples of cr-alumina pellets prepared under different compressing pressures and calcination temperatures with pore structures resembling commercial catalysts/carriers were used. Responses to composition step changes at one face of cylindrical pellets were followed at the other pellet face. The dusty gas model (DGM) and mean pore transport model (MTPM), based on the modified Maxwell-Stefan equation and Darcy law, were used for simulation of experimental responses with transport parameters obtained from dynamic measurements with binary gas mixtures. The predicted and measured responses to step changes of gases agreed very well for both models.