Abstract
Global hydrogen demand is accelerating as nations strive to meet Net-Zero 2050 targets. Currently, Steam Methane Reforming (SMR) of natural gas supplies approximately 48% of the world’s hydrogen but is hindered by high carbon intensity (approx. 9 kg CO2/kg H2). This study presents a comprehensive technical analysis of the SMR process, identifying critical bottlenecks in catalyst stability and thermodynamic efficiency. We specifically investigate the deactivation mechanisms of nickel-based catalysts (Ni/Al2O3), distinguishing between whisker carbon formation and thermal sintering. Through a comparative sustainability assess- ment, we evaluate the transition from “Gray” to “Blue” hydrogen. Our analysis of project data reveals that while Blue Hydrogen significantly reduces Global Warming Potential (GWP), the integration of Carbon Capture, Utilization, and Storage (CCUS) in- creases the electrical energy requirement from 0.96 kWh/kg to 4.42 kWh/kg. Furthermore, we critically review emerging Chemical Looping Reforming (CLR) technologies as a means to bypass the energy penalty of conventional amine scrubbing. The study concludes that optimizing catalyst geometry and support interaction is a prerequisite for the economic viability of the hydrogen economy.



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