International Journal of Hydrogen Energy, Vol.45, No.12, 7433-7443, 2020
Identification of hydrogen permeability parameters of membrane materials in an aggregated experiment
The study of the hydrogen permeability of materials for membrane-based separation/purification technologies employs a variety of experimental methods with their own specific features, advantages and shortfalls. The method of penetration with vacuum pumping allows determining the diffusion coefficient from so-called lag time. The accuracy of the estimation depends on the degree of proximity to the DLR (diffusion limited regime) mode. The method of "communicating vessels" is more sensitive to surface processes. The thermal desorption (TDS) technique permits "scanning" the material dynamically across a wide range of temperatures. "Separate" application of these methods leads to a situation where the materials studied are in fact somewhat different (for example, due to different impacts on the surface), and significant differences in parameter estimates ensue. This paper suggests and implements a technique for a combined three-stage ((penetration (with and without vacuum pumping)+TDS)) experiment and the corresponding mathematical toolkit. The informative capacity of the experiments and the accuracy of the estimation of hydrogen permeability parameters (adsorption, dissolution, diffusion and desorption) of the membrane materials under study are thus enhanced. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.