Study on the Hydrogen Production Characteristics of Sorption-Enhanced Steam Reforming of Shale Gas Using Calcium-Based Adsorbents

Abstract This study presents a thermodynamic analysis of hydrogen (H2) production via shale gas steam reforming (SG-SR) and shale gas sorption-enhanced steam reforming (SG-SESR). The analysis was performed using HSC Chemistry software based on the principle of Gibbs free energy minimization. First, the influence of key operating parameters, such as the steam-to-carbon molar ratio (S/C), temperature, and pressure, on the H2 yield and concentration, carbon-containing gas concentration, and carbon deposition during the SG-SR process was investigated. The results showed that the optimal reaction conditions were 700°C, 0.10 MPa, and S/C = 4. Under these conditions, the H2 yield and concentration (on a dry gas basis) were 4.04 mol/mol and 84.05%, respectively. Subsequently, the impact of the CaO-to-carbon molar ratio (CaO/C) on SG-SESR, as well as the synergistic effects of S/C and CaO/C, were explored. The results demonstrated that when the temperature was controlled within 500–600°C with S/C = 6 and CaO/C = 2, the H2 yield reached 4.30 mol/mol, and the concentration peaked at 99.66%. This thermodynamic analysis of SG-SR and SG-SESR processes not only advances the comprehensive SG utilization and the development of novel clean hydrogen production technologies but also provides theoretical guidance for the practical application of shale gas reforming.