The Flow of Fluids Through Activated Carbon Rods.

Abstract

The flow rates of the vapors of benzene, ethyl chloride, diethyl ether, methanol, and water through activated carbon rods have been found to exceed, considerably, flow rates calculated by classical equations. The excess flow rates show maxima in widely different relative pressure regions and are ascribed t o flow of adsorbed material. An empirical equation is presented which correlates the observed flour rates with relevant adsorption isotherms. Classical equations of flow through elliptical and rectangular pipes are discussed with reference to flow through finegrained porous materials. I t is shown that equations of the Adzumi type are roughly valid as applied to line-grained porous bodies, but that without a knowledge of the frequency distributions of pore sizes and shapes, flow data cannot be related to pore dimensions in any literal sense. End effects are discussed.

On the surface diffusion of adsorbable gases through porous media

“…2. Hydrodynamic model, which pictures the adsorbed gas as being a liquid film slipping on the solid surface w3h a laminar flow (Flood et al, 1952;Gilliland et al, 1958;Babbit, 1950). 3.…”

Adsorption–Desorption Flow of Condensable Vapors through Mesoporous Media: Network Modeling and Percolation Theory

“…The average conductivity values are calculated based on the average pore size which in the present case is 50Å. For such a system the properties of the percolation cluster are determined by two characteristic scales, the correlation length, ξ , given by the following expression, where f cc is the percolation threshold of closed (capillary condensed) pores, and the mixed conductivity scale l p is defined by (26,27) l p = γ −ν/(s+w) , [13] where γ = g poor /g good and ν, s, w are universal critical exponents which depend on the dimensionality of the network. For a three-dimensional network ν = 0.88, w = 2.00 ± 0.02, and s = 0.735 ± 0.003 (27, 35-37, 54, 55).…”

“…Despite the early and recent experimental findings (12)(13)(14)(15)) and the immediate impact in gas separations using membrane technology (5,7), only a few theoretical models have been successfully employed to explain this peculiar behavior (for a review see for example (11)). The most popular mechanism so far has been the one developed originally by Rhim and Hwang (9) and later modified in its present form by Lee and Hwang (10).…”

Capillary rise in porous media

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