Synthesis and Characterization of Mn–Ce–VOx/TiO2 Nanocomposite for SCR of NOx at Low Temperatures: Role of Mn, Ce and V Oxide

Synergistic mechanism of supported Mn-Ce oxide in catalytic ozonation of nitrofurazone wastewater

In this study, the catalytic materials of MnO_x/γ-Al₂O₃, CeO₂/γ-Al₂O₃, and Mn_xCe_1-xO₂/γ-Al₂O₃ for catalytic ozonation were synthesized. The catalysts were used in heterogeneous catalytic ozonation of the wastewater containing ntrofurazone (NFZ). The effects of the catalytic ozonation operational factors were systematically evaluated in terms of ozone dosing, catalyst dosing, initial NFZ concentration, and pH. The results showed that the catalytic activity of the Mn_xCe_1-xO₂/γ-Al₂O₃ was higher than that of the MnO_x/γ-Al₂O₃ and CeO₂/γ-Al₂O₃. The kinetics analysis revealed that bimetallic loading has a synergistic effect and the mechanism of this effect was investigated in the catalytic ozonation system. The catalysts were characterized by FESEM, EDS, XRD, XPS, IR, and BET. The characteristics of the catalysts revealed that Mn could alter the oxide species on the metal surface and interfere with the formation of CeO₂ crystals, which led to smaller grains, enhanced adsorption oxygen, and greater specific surface area. The Mn_xCe_1-xO₂/γ-Al₂O₃ crystals could form a solid solution, which helps higher catalytic activity. This study adds to the understanding of the synergistic mechanism of the loaded Ce-Mn oxide catalysts in the heterogeneous catalytic ozonation system and provides a feasible method for degrading pharmaceutical wastewater.

Recent progress of low-temperature selective catalytic reduction of NOx with NH3 over manganese oxide-based catalysts

Selective catalytic reduction with NH3 (NH3−SCR) was the most efficient approach to mitigate the emission of nitrogen oxides (NOx). Although the conventional manganese oxide-based catalyst had gradually become a kind...

Effect of FeOx and MnOx doping into the CeO2–V2O5/TiO2 nanocomposite on the performance and mechanism in selective catalytic reduction of NOx with NH3

FeO_x–CeO₂–V₂O₅/TiO₂ catalyst showed higher N₂ selectivity and resistance to SO₂ and H₂O than MnO_x–CeO₂–V₂O₅/TiO₂ catalyst due to their different physicochemical properties. The interaction of Fe, Ce and V oxides and reaction mechanism were explored.