Ensemble process for producing high-purity H2 via simultaneous in situ H2 extraction and CO2 capture

Abstract

To produce fuel-cell-grade hydrogen (H 2 ) via fossil fuel reforming processes, an efficient H 2 purification method with a carbon capture unit is necessary. In this study, a sorption-enhanced water-gas shift membrane reactor (SE-WGS-MR) system combining a state-of-the-art MgO-based catalyst, carbon dioxide sorbent, and Pd/Ta membrane is developed to simultaneously capture carbon dioxide and purify H 2 . With the optimal sorption-enhanced configuration (SE-WGS), the carbon monoxide conversion is significantly enhanced to 86.6%, compared with 68.5% using the commercial catalyst only. Coupling of the Pd/Ta membrane with the WGS catalyst (WGS-MR) enable over 95% H 2 recovery, with the production of high-purity H 2 . Eventually, the ensemble of the three processes (SE-WGS-MR) afford 99.99% of carbon monoxide conversion and the extraction of high-purity H 2 with 99.5% recovery. This study demonstrates the potential of the single process integrating the catalytic reaction, adsorptive separation, and membrane purification for the production of H 2 with ultra-high purity and recovery. • Integration of WGS catalyst and CO 2 sorbent with a Pd/Ta membrane is examined • Coupling of the Pd/Ta membrane with the WGS catalyst enables over 95% H 2 recovery • Simultaneous CO 2 capture and H 2 purification shifts the CO conversion to 99.99% • The ensemble of the processes extracts ultra-pure H 2 with over 99.5% recovery Jin et al. propose an effective ensemble process for producing pure H 2 via simultaneous in situ H 2 extraction and CO 2 capture. Integration of MgO-based catalyst and CO 2 sorbent with a Pd/Ta composite membrane shifts the CO conversion to 99.99%, enabling the extraction of pure H 2 with over 99.5% recovery.