One of the most significant aspects in selective catalytic reduction (SCR) of nitrogen oxides (NO x ) is developing suitable catalysts by which the process occurs in a favorable way. At the present work SCR reaction by ammonia (NH 3 -SCR) was conducted using Co-Mn spinel and its composite with Fe-Mn spinel, as nanocatalysts. The nanocatalysts were fabricated through liquid routes and then their physicochemical properties such as phase composition, degree of agglomeration, particle size distribution, specific surface area and also surface acidic sites have been investigated by X-ray diffraction, Field Emission Scanning Electron Microscope, Energy-dispersive X-ray spectroscopy, energy dispersive spectroscopy mapping, Brunauer–Emmett–Teller, temperature-programmed reduction (H 2 -TPR) and temperature-programmed desorption of ammonia (NH 3 -TPD) analysis techniques. The catalytic activity tests in a temperature window of 150–400 °C and gas hourly space velocities of 10,000, 18,000 and 30,000 h −1 revealed that almost in all studied conditions, CoMn 2 O 4 /FeMn 2 O 4 nanocomposite exhibited better performance in SCR reaction than CoMn 2 O 4 spinel.

中文翻译：

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钴锰基纳米催化剂对NO的选择性催化还原

氮氧化物（NO x）的选择性催化还原（SCR）的最重要方面之一是开发合适的催化剂，通过该催化剂以有利的方式进行该过程。在目前的工作中，使用Co-Mn尖晶石及其与Fe-Mn尖晶石的复合物作为纳米催化剂，通过氨气（NH 3 -SCR）进行SCR反应。纳米催化剂是通过液相途径制备的，然后通过X射线衍射，场发射扫描电子显微镜，能谱法研究了它们的理化性质，如相组成，团聚度，粒度分布，比表面积以及表面酸性部位。色散X射线光谱法，能量色散光谱图，布鲁诺尔-埃米特-泰勒，程序升温还原（H 2 -TPR）和程序升温解吸氨（NH 3 -TPD）分析技术。在150-400°C的温度范围内以及10,000、18,000和30,000 h -1的气体时空速度下进行催化活性测试，结果表明，几乎在所有研究条件下，CoMn 2 O 4 / FeMn 2 O 4纳米复合材料在室温下均表现出更好的性能。 SCR反应比CoMn 2 O 4尖晶石高。