Permeation of gases in inhomogeneous polymeric membranes at unsteady state

Akon Higuchi, Tsutomu Nakagawa

Research output: Contribution to journalArticlepeer-review

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Flux and concentration profiles in inhomogeneous polymeric membranes at an unsteady state were obtained by solving the continuous equation with a finite difference method:(Equation Check) where P is the permeability coefficient, S is the solubility, C is the concentration in the membrane, pm, is a hypothetical pressure in the membrane defined by C/S, x is the dimensionless space coordinate, t is the time, and L is the membrane thickness. The membranes are considered to be in a rubbery state and to have continuous, concentration-dependent, gradients of solubility and diffusivity along the flux direction (x axis), The time lag of the inhomogeneous membranes was estimated to disagree with the value calculated by L2/6D, where D is the diffusion coefficient. The flux difference due to the flow direction at the unsteady state was also investigated, and was found to be slightly higher than the flux difference in the steady state.

Original languageEnglish
Pages (from-to)619-624
Number of pages6
JournalSen'i Gakkaishi
Issue number11
StatePublished - Apr 1992


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