Effect of blending hydrogen into natural gas on selective catalytic reduction of NOx for stationary power applications using a V2O5-WO3/TiO2 catalyst

This study investigates the impact of hydrogen blending into natural gas on the selective catalytic reduction (SCR) of NO x in stationary power applications using a V 2 O 5 –WO 3 /TiO 2 -based commercial SCR catalyst. Results indicate that blending hydrogen up to 100 % does not inhibit NO x conversion, even at high water vapor concentrations (up to 34 %) resulting from hydrogen combustion, and an increase in NO x conversion is observed with hydrogen addition. Lean combustion conditions enhance NO x conversion due to excess oxygen. While increasing SO 2 concentration (up to 500 ppm) reduces SCR activity, 100 % hydrogen cases exhibit higher NO x conversion, showing improved sulfur tolerance due to high water content favoring the formation of surface sulfate species rather than sulfites, enhancing catalyst acidity. These findings demonstrate that SCR units can effectively operate without modification when transitioning to hydrogen–natural gas blends, offering a promising route for decarbonizing stationary power systems without compromising NO x control performance. • Hydrogen blending up to 100 % does not impair NO x conversion of SCR catalysts. • No modifications needed on SCR units for transitioning to H 2 –natural gas blends. • Leaner fuel mixtures improve NO x conversion due to excess oxygen. • Higher H 2 O content in flue gas enhances Brønsted acidity and sulfur resistance. • SCR process remains effective under high NO and SO 2 concentrations.