Thermodynamic calculation for the activity and mechanism of Mn/TiO2 catalyst doped transition metals for SCR at low temperature

• NO conversion: CuO > Co3O4 > NiO > Fe2O3 > Cr2O3 > ZnO > La2O3 > CeO2 > ZrO2.
• Ellingham Diagrams are in accordance with NH3-SCR performance.
• NH3-SCR activity is line with the ammonia oxidation with transition metals.
• Ellingham Diagrams supply a theoretical and workable way to select SCR catalysts.

The introduction of transition metals in Mn/TiO2 catalysts played significant roles in oxidative abstraction of hydrogen from adsorbed ammonia during the selective catalytic reduction (SCR). Thermodynamic calculation studies showed that the SCR performance was in accordance with the ammonia oxidation with transition metals, and the reaction tendency for the ammonia oxidation was decreased in the following order: CuO > Co3O4 > NiO > Fe2O3 > Cr2O3 > ZnO > La2O3 > CeO2 > ZrO2. In addition, Mn/TiO2 catalyst doped metal (Fe and Cu) oxides enhanced performance for NOx conversion, being approximately 100% at 453 K.

Ellingham Diagrams were in line with the NO conversion and the ammonia oxidation with transition metals, which might supply a theoretical way to select proper metal oxides for NH3-SCR.Figure optionsDownload as PowerPoint slide