Adsorption, diffusion and permeation of gases in microporous membranes. III. Application of percolation theory to interpretation of porosity, tortuosity, and surface area in microporous glass membranes

Prediction of carbon dioxide permeability in carbon slit pores

“…For CMS and polyimide, the solubility coefficients (S) derived from the adsorption isotherms show relatively small differences between simulation results and experimental data. Since the experimental permeability was measured in membranes having complex pore networks, the effects of porous structure on the membrane mass transport were taken into account for the effective diffusivity (D eff ), introducing the so-called tortuosity ( ) and the porosity (ε) [54]. As far as there are impermeable obstacles, the diffusing molecules have to follow a more tortuous path to go through the membrane [55].…”

Theory of gas diffusion and permeation in inorganic molecular‐sieve membranes

“…It was manufactured in limited quantities with relatively good reproducibility of its gas separation properties. Detailed experimental investigations of gas transport properties in this type of molecular-sieve inorganic glass membrane were carried out by Way and Roberts (1992), Roberts et al (1992), Bhandarkar et al (1992), and Shelekhin et al (1992Shelekhin et al ( , 1993.…”

“…less than 2 nm, at temperatures higher than 300 K. With these assumptions, the transport processes in microporous membranes may be represented by the Knudsen and/or configurational diffusion mechanisms, possibly combined with surface flow. Experimental measurements on the microporous glass membranes suggest that pores with approximate diameter equal to 15+5 A are formed (Hammel, 1989;Hammel et al, 1989;Bhandarkar et al, 1992;Shelekhin et al, 1993) due to the specifics of the membrane preparation technique. Large pores inside the membrane ( -15 A) are interconnected by pore necks which are smaller in diameter ( Figure 1).…”

Modeling of Aqueous Transport in Rigid Porous Matrices near the Percolation Threshold

“…As ; increases, transport approaches the conventional relationship of path length (L) to time (t) shown in Eq. (8).…”

“…Applications of percolation theory in pharmaceutical and other industries are manifold, with the method being used to predict behavior of disordered systems in areas as diverse as separations processing (8,9), water vapor transport (10), tablet granulation and compression (11Y15), and release control in different drug delivery systems (16Y18). While this list is by no means intended as an exhaustive review of the field, these references speak to the power of the method in characterizing and predicting certain behaviors of complex systems through simple measurements of key bulk properties.…”