A new hydrogenation-coupling approach for supra-equilibrium conversion in a water–gas shift reaction: Simultaneous hydrogen generation and chemical storage

This work reports a practical system of hydrogenation-coupled water–gas shift reaction (HC-WGSR) for simultaneous hydrogen production and storage. The performance of the HC-WGSR system was predicted through thermodynamic simulation. The proof-of-concept tandem water–gas shift and propene hydrogenation strategy was successfully demonstrated using a bifunctional catalyst. The hydrogen produced from the WGSR was successfully stored in propane simultaneously, and the overall CO conversion of nearly 100% overcame the equilibrium limitation of the WGSR over a wide range of space velocities (3000 - 6000 h⁻¹) at 200 ^°C and 1 bar. This study demonstrated that the in situ removal/storage of H₂ using the hydrogenation-coupling approach is promising even in a CO₂-rich environment (20% CO₂). The new approach shall see a great opportunity in using organic hydrogen carriers, e.g., benzene, toluene, N-ethylcarbazole, to expand the industrial applications, underpinning the global supply chain for hydrogen energy.