An in-situ DRIFTs study of Mn doped FeVO4 catalyst by one-pot synthesis for low-temperature NH3-SCR

Abstract Manganese doped FeVO4 catalysts were synthesized through a novel “one-pot method,” and the influence of Mn doping on FeVO4 in the selective catalytic reduction of NOx with NH3 (NH3-SCR) reaction was in-depth studied. The 0.3Mn-FeV catalyst showed superior deNOx performance, reaching a 100% NOx conversion rate at 250 °C as a remarkable catalyst. The study of XRD, HR-TEM, XPS, H2-TPR, and NH3-TPD results showed that the introduction of Mn improved the crystal size, the acidity and redox of the catalyst, and maintained the V species in a higher valence state, which is conducive to activation of NH3. The SCR reaction performed on 0.3Mn-FeV at 175 °C followed the Langmuir-Hinshelwood (L-H) mechanism. The reaction was presented as two types: “standard SCR” and “fast SCR.” The Eley-Rideal (E-R) mechanism was mainly introduced at 250 °C, and the –NH2 species played a crucial factor in determining the NO reduction rate.