Improvement of catalytic activity over Mn-modified CeZrOx catalysts for the selective catalytic reduction of NO with NH3.
Improvement of catalytic activity over Mn-modified CeZrOx catalysts for the selective catalytic reduction of NO with NH3.
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DOI：
10.1016/j.jcis.2018.07.050
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发表时间：
2018-12
影响因子：
9.9
通讯作者：
Wenbo Sun;Xinyong Li;Jincheng Mu;Shiying Fan;Zhifan Yin;Xinyang Wang;Meichun Qin;M. Tadé;
中科院分区：
文献类型：
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作者：
Wenbo Sun;Xinyong Li;Jincheng Mu;Shiying Fan;Zhifan Yin;Xinyang Wang;Meichun Qin;M. Tadé;
采用浸渍-氨水共沉淀法制备了一系列MnCeZrOx复合氧化物催化剂，并对催化剂进行了NH3选择性催化还原（SCR）脱硝性能的研究。掺杂锰显著提高了催化活性，并且表现最好的SCR催化剂Mn 0.25Ce 0.5Zr 0.25Ox显示在温度范围内实现了> 80%的NO转化率（60-350 °C），室温下的脱水效果可达50%（条件：[NO] = [NH3] = 500 ppm，[O2] = 5体积%，He作为余量，流速= 100 mL/min，GHSV = 40，000 h-1）。通过BET、XRD、XPS、H2-TPR和原位FTIR等表征手段对催化剂进行了表征，结果表明，Mn的引入使催化剂的比表面积增大，还原能力增强，表面吸附氧增加，从而提高了催化剂的SCR活性。通过原位红外光谱分析，研究了Mn_（0.25）Ce_（0.5）Zr_（0.25）O_x催化剂上的SCR反应机理，发现该催化剂上的SCR反应主要遵循E-R机理。
A series of MnCeZrOxmixed oxide catalysts were facilely synthesized using the impregnation-NH3·H2O coprecipitation method and tested for selective catalytic reduction (SCR) of NO with NH3. Doping manganese significantly improved the catalytic activity and the best performing SCR catalyst, Mn0.25Ce0.5Zr0.25Ox, was shown to achieve NO conversion > 80% in the temperature range (60–350 °C), with the denitration effect up to 50% at room temperature (conditions: [NO] = [NH3] = 500 ppm, [O2] = 5 vol%, He as balance, flow rate = 100 mL/min, GHSV = 40, 000 h−1). Characterization of the catalyst using BET, XRD, XPS, H2-TPR, andin-situFTIR proved that the improved SCR activity may be attributed to the large surface area, great reduction ability and increased amount of surface adsorbed oxygen afforded by the introduction of manganese. The SCR reaction mechanisms were also investigated by analyzingin-situFTIR spectra and the SCR reaction pathway over the Mn0.25Ce0.5Zr0.25Oxcatalyst was shown to mostly follow the E-R mechanism.