Adsorption and Mass Transport of Methane and Hydrogen in Nanoporous Carbon Membranes - Binary Mass Transport Experiments and Modeling

This study investigates binary mass transport of methane (CH4) and hydrogen (H2) through carbon-based nanoporous membranes at elevated temperatures. Building upon previous single-component adsorption and permeation measurements, we present new binary permeation experiments conducted up to 220 °C and develop a predictive transport model based on the Maxwell–Stefan (M–S) framework. Initial model predictions underestimated H2 flux, which were resolved by incorporating a confinement correction to account for slit pore geometry and a temperature-dependent scaling factor. These modifications significantly improved model accuracy and alignment with experimental data. The refined model was extrapolated to 500 °C and varying gas compositions to evaluate membrane selectivity under relevant process conditions, thus offering predictive capabilities for membrane-based separations applicable to hydrogen production and carbon utilization.