Du Yali, Liu Lili, Feng Yalin, Yang Baoshuan, Wu Xu
College of Chemistry and Chemical Engineering, Jinzhong University Jinzhong 030619 PR China
College of Chemistry and Chemical Engineering, Taiyuan University of Technology Taiyuan 030024 PR China
RSC Adv. 2019 Dec 2;9(68):39699-39708. doi: 10.1039/c9ra08391j.
Transition metal (Cu, Ni, Co) doped MnAl mixed oxide catalysts were prepared through a novel method involving the calcination of hydrotalcite precursors for the selective catalytic reduction of NO with NH (NH-SCR). The effects of transition metal modification were confirmed by means of XRD, BET, TEM, XPS, NH-TPD, and H-TPR measurements. Experimental results evidenced that CoMnAl-LDO presented the highest NO removal efficiency of over 80% and a relatively high N selectivity of over 88% in a broad working temperature range (150-300 °C) among all the samples studied. Moreover, the CoMnAl-LDO sample possessed better stability and excellent resistance to HO and SO. The reasons for such results could be associated with the good dispersion of CoO and MnO , which could consequently provide optimum redox behavior, plentiful acid sites, and strong NO adsorption ability. Furthermore, dynamics calculations verified the meaningful reduction in apparent activation energy ( ) for the CoMnAl-LDO sample, which is in agreement with the DeNO activity.
通过一种涉及水滑石前驱体煅烧的新方法制备了过渡金属（铜、镍、钴）掺杂的锰铝混合氧化物催化剂，用于以氨选择性催化还原氮氧化物（NH₃-SCR）。通过XRD、BET、TEM、XPS、NH₃-TPD和H₂-TPR测量证实了过渡金属改性的效果。实验结果表明，在所研究的所有样品中，CoMnAl-LDO在较宽的工作温度范围（150 - 300°C）内呈现出最高的NO去除效率，超过80%，以及相对较高的N₂选择性，超过88%。此外，CoMnAl-LDO样品具有更好的稳定性以及对H₂O和SO₂的优异抗性。这些结果的原因可能与CoO和MnO₂的良好分散有关，这进而能够提供最佳的氧化还原行为、丰富的酸性位点和较强的NO吸附能力。此外，动力学计算证实了CoMnAl-LDO样品的表观活化能（Ea）有显著降低，这与脱硝活性一致。
