Development of In-Situ Hydrogen Permeation Measurement Technology Based on Volumetric and Manometric Analysis of Polymer Specimen under High Pressure Hydrogen Environment

Abstract

Two in situ high-pressure permeation measurement systems were developed to assess the hydrogen permeation propertiesof the polymer sealing materials in high-pressure hydrogen environments. These systems enable real-time monitoring of hydrogenpermeation after the injection of high-pressure hydrogen using both volumetric and manometric analyses for the precisequantification of hydrogen gas moles. With the integration of a custom-designed diffusion-permeation analysis program, systems canaccurately calculate the key properties such as hydrogen diffusivity, permeability, and solubility. Hydrogen permeation tests were performedon Ethylene Propylene Diene Monomer (EPDM) materials with carbon black fillers, which are commonly used as O-ringseals in high-pressure hydrogen applications, to validate the system performance. The tests were performed across a pressure rangeof 1–10 MPa, and the results showed a decrease in hydrogen permeability and diffusivity as the pressure increased, whereas the solubilityremained constant. This implies that hydrogen permeation in the polymer is mainly influenced by diffusion rather than solubility. In both systems, the H2 uptake of the EPDM specimen conformed to Henry’s law. The measurement results of the twosystems were consistent with the uncertainties, which confirms the reliability of the two systems for evaluating hydrogen permeabilityunder high-pressure conditions.