Gonçalves Alexandre A S, Ciesielczyk Filip, Samojeden Bogdan, Jaroniec Mietek
Department of Chemistry and Biochemistry, Kent State University, Kent, OH 44240, United States.
Faculty of Chemical Technology, Institute of Chemical Technology and Engineering, Poznan University of Technology, PL-60965 Poznan, Poland.
J Hazard Mater. 2021 Jan 5;401:123413. doi: 10.1016/j.jhazmat.2020.123413. Epub 2020 Jul 7.
Insertion of transition metal species into crystalline alumina at low temperatures is proposed to achieve the dispersion of these species at atomic level paired with exceptional textural properties. Precisely, MeAlO/γ-AlO (Me = Mn, Fe, Co, Ni, and/or Cu) nanostructured ceramic catalysts were fabricated with ultra large mesopores (16-30 nm), and high specific surface area (180-290 m g) and pore volume (1.1-1.6 cm g). These ceramics were applied as efficient catalysts for the selective catalytic reduction (SCR) of NO with NH, and their selectivity was discussed in terms of NO formation, an undesirable byproduct. The catalysts containing Fe, Cu, or Mn showed the highest activities, however, within different temperature ranges. Further tuning of the catalytic activity and selectivity was achieved by creating ceramic catalysts with mixed compositions, e.g., CuFe and MnFe. Upon insertion of the transition metal species into crystalline structure of alumina to maximize atom efficiency, the NO formation profile did not change significantly for all metal aluminates except MnAlO, indicating that these catalysts are suitable for SCR and selectively promote the reduction of NO.
有人提出在低温下将过渡金属物种插入结晶氧化铝中，以实现这些物种在原子水平上的分散，并具备优异的织构性质。具体而言，制备了具有超大介孔（16 - 30纳米）、高比表面积（180 - 290平方米/克）和孔体积（1.1 - 1.6立方厘米/克）的MeAlO/γ - AlO（Me = Mn、Fe、Co、Ni和/或Cu）纳米结构陶瓷催化剂。这些陶瓷被用作以NH₃选择性催化还原（SCR）NO的高效催化剂，并从不需要的副产物NO生成的角度讨论了它们的选择性。含有Fe、Cu或Mn的催化剂表现出最高的活性，不过是在不同的温度范围内。通过制备具有混合组成的陶瓷催化剂，如CuFe和MnFe，进一步调节了催化活性和选择性。在将过渡金属物种插入氧化铝的晶体结构以最大化原子效率时，除MnAlO外，所有金属铝酸盐的NO生成曲线没有显著变化，这表明这些催化剂适用于SCR，并能选择性地促进NO的还原。
