Abstract
The piezometric method used for the measurement of diffusion coefficients in microporous solids is examined in an attempt to establish the limits of applicability. In the present study isothermal conditions are assumed. The theoretical model for the description of the transient behaviour is linearized and solved to yield analytical solutions. The effect of the physical parameters governing the system response is described. It appears that severe limitations must be considered for strongly adsorbed and fast diffusing species.
Based on the results it is possible to suggest improvements to the experimental technique and an alternative approach to analyze the experimental response curves, in which the only unknown parameter is the diffusional time constant.
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Brandani, S. Analysis of the Piezometric Method for the Study of Diffusion in Microporous Solids: Isothermal Case. Adsorption 4, 17–24 (1998). https://doi.org/10.1023/A:1008831202564
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DOI: https://doi.org/10.1023/A:1008831202564