Intensifying steam methane reforming and water-gas shift in tandem via rapid pulsed Joule heating

Steam methane reforming (SMR) is the primary industrial method for syngas (a mixture of carbon monoxide (CO) and hydrogen (H 2 )) and H 2 production. SMR is one of the most carbon-intensive processes. Due to the ineffectiveness of the water-gas shift (WGS) reaction at the high SMR temperatures, high-purity H 2 requires two downstream WGS reactors. This study demonstrates how dynamic Joule heating can intensify SMR and WGS in a single reactor, boosting H 2 yield. We show that rapid pulsing drives methane conversion and H 2 /CO ratios beyond steady-state limits, mostly at higher pressures and steam-rich feeds through thermodynamic analysis, transient kinetic modeling, and experiments. Our simulations highlight the role of pulse shape in maximizing both conversion and H 2 /CO ratios leveraging high- and low-temperature regimes. Experimental results confirm that pulsed heating is more efficient than conventional and steady-state heating, maximizing H 2 productivity and reforming rates. These findings position rapid pulsed Joule heating as an intensifying approach to integrate high-temperature endothermic and low-temperature exothermic, equilibrium-limited reactions.