Bulk Vanadium Oxide versus Conventional V2O5/TiO2: NH3–SCR Catalysts Working at a Low Temperature Below 150 °C

作者：Yusuke Inomata, Shinichi Hata, Makoto Mino, Eiji Kiyonaga, Keiichiro Morita, Kenji Hikino, Kazuhiro YOSHIDA, Hiroe Kubota, Takashi Toyao, Ken‐ichi Shimizu, Masatake Haruta, Toru Murayama · 发表于：ACS Catalysis · 年份：2019 · DOI：10.1021/acscatal.9b02695 · 被引用次数：119 · 研究领域：Catalytic Processes in Materials Science、Catalysis and Oxidation Reactions、Transition Metal Oxide Nanomaterials

Practical catalysts that work at a low temperature for selective catalytic reduction of NO x using NH 3 (NH 3 –SCR) have been required to treat NO x at the outlet temperature in boiler systems (100–150 °C). In this paper, we report bulk vanadium oxide catalysts that show NH 3 –SCR activity at a low temperature below 150 °C. Defective bulk vanadium oxide (V(V)+V(IV)) catalysts were synthesized by the calcination of vanadium(IV)-oxalate at 270 °C (1–4 h). The reaction rate per mol of surface vanadium atom of the catalyst calcined at 270 °C for 2 h (V 270-2, 6.4 × 10 –2 mol NO mol V –1 s –1 ) was 10–14 times faster than those of conventional 1–9 wt % V 2 O 5 /TiO 2 (4.5 × 10 –3 –6.1 × 10 –3 mol NO mol V –1 s –1 ), indicating that bulk vanadium oxide is more favorable for NH 3 –SCR and V(IV) species enhance the activity. The NH 3 –SCR of V 270-2 is driven by the Lewis acid mechanism, which proceeds faster than the Brønsted acid mechanism.