Two-stage VSA/PSA for capturing carbon dioxide (CO2) and producing hydrogen (H2) from steam-methane reforming gas

Abstract A two-stage vacuum/pressure swing adsorption (VSA/PSA) process has been investigated for CO2 capture and then H2 production from steam methane reforming (SMR) gas mixture. The target is to produce ultra-pure hydrogen and high-purity CO2. Many fundamental research studies have been carried out to validate the accuracy of numerical calculation, such as isotherm measurement, fitting and process modelling. The results indicate that the first stage process could produce 95.31% CO2 with the recovery of 90.93% and the second stage could produce 99.9952% H2 with an overall recovery of 71.16%. Variable analysis, optimal conditions and comparison with other processes are discussed in detail.