Collection of Czechoslovak Chemical Communications - digital archive 

Abstract

A spontaneous temporary rise in the pressure gradient through countercurrent binary transport of inert gases in porous bidispersed alumina was observed in diffusion cell of the Wicke-Kallenbach type. Experimental pressure responses to gas step changes were detected and fitted to a set of partial differential equations. These were based on the transport models Mean Transport Pore Model (MTPM) and Dusty Gas Model (DGM). The dynamic set transport parameters 〈r〉, 〈r²〉 and ψ for both models were obtained using an optimization algorithm and discussed. It was found that the values of the transport radius 〈r〉 are in a good agreement with the mean radius obtained from the measurement of alumina texture.

Keywords: Diffusion; Gas permeation; Porous structure model; Alumina; Porous materials.