Modeling particle uptake and release in porous carbon to support cryosorption pump design

Rational design of high-performance cryosorption pumps requires decoupling intrinsic material properties from complex geometric effects. However, predicting performance limits is challenging because the hierarchical pore structure of activated carbon complicates the relationship between microscopic adsorption and macroscopic gas release. To address this, we developed an isothermal test-particle Monte Carlo simulation framework that models particle dynamics within representative pore structures. We propose the release starting time, defined as the time to reach a specific release fraction (e.g., %), as a practical and robust metric. Our simulations demonstrate that this metric is largely insensitive to structural variations such as pore depth and connectivity. This robustness substantiates the utility of the release starting time as a structure-independent indicator that directly reflects the distribution of effective adsorption potential values ( ). Building on this insight, we present a method to estimate the shape of this distribution by comparing activation energies at different release fractions. This approach provides a physically grounded framework to interpret observable gas release behaviors, linking a material’s microstructure to its macroscopic release characteristics. By offering a new tool to support material selection and performance prediction, this study advances cryosorption pump development beyond empirical trial-and-error.