Permeation through a membrane with differing surface conditions on the inlet and outlet sides was analyzed. Two regime parameters characterizing the rates of processes on two sides of the membrane with respect to the rate of bulk diffusion were introduced. These parameters determined the concentration profile and the permeation rate. General equations for the concentration and permeation flux were obtained. Three basic regimes were considered as partial limiting cases of the general equations. These were diffusion-limited, outlet surface regime and inlet surface limited regime. The latter has two modes with qualitatively different concentration profiles. Boundaries between the regimes and approximation formulae for the permeation rates in these regimes were found. Features of permeation in the limit cases and in intermediate regions were analyzed.

Hydrogen Gas-Driven Permeation through the Membrane with Asymmetric Surface Conditions. A.Pisarev: Journal of Membrane Science, 2009, 335[1-2], 51-7