Macroporous SmMn2O5 mullite for NOx-assisted soot combustion
Macroporous SmMn2O5 mullite for NOx-assisted soot combustion
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用于 NOx 辅助烟灰燃烧的大孔 SmMn2O5 莫来石
DOI：
10.1039/c6cy02478e
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发表时间：
2017-02-21
影响因子：
5
通讯作者：
Shan, Bin
中科院分区：
文献类型：
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作者：
Feng, Zijian;Liu, Qinhan;Shan, Bin
采用柠檬酸法（CA）、水热法（HT）和共沉淀法（CP）以及乙二醇和甲醇溶液（EG&M）燃烧法制备了一系列莫来石型SmMn2O5氧化物，并进行了nox辅助烟尘燃烧试验。在“松散”接触条件下进行了催化剂性能测试，并通过XRD、FTIR、BET、SEM、XPS以及O2-TPD和H2-TPR测试对催化剂的理化性质进行了表征。SmMn2O5-EG&M催化剂具有明显的板状结构，板状结构由相互连接的大孔分隔，总体上表现出最高的烟尘燃烧催化活性。相应的T10、T50和T90分别为283℃、368℃和420℃，CO2选择性为99.6%。SmMn2O5-EG&M催化剂的烟尘燃烧活化能为65 kJ mol−1。O2-TPD和H2-TPR测量表明，EG&M样品的表面吸附氧具有更高的迁移率和更好的还原性。在NO + O2气氛下，no2辅助机制大大加速了烟尘的燃烧，催化剂的大孔相互连接进一步促进了烟尘与催化剂的紧密接触。研究表明，SmMn2O5莫来石是nox辅助烟尘燃烧的有效催化剂。
A series of mullite SmMn2O5 oxides were prepared by citric acid (CA), hydrothermal (HT) and co-precipitation (CP) and combustion of ethylene glycol and methanol solutions (EG&M) methods, and tested for NOx-assisted soot combustion. The catalyst performance tests were conducted under “loose” contact conditions and the physical and chemical properties characterized by XRD, FTIR, BET, SEM, XPS, and O2-TPD and H2-TPR measurements. The SmMn2O5-EG&M catalyst possessed a distinct morphology with slabs separated by interconnected macropores, and exhibited the overall highest catalytic activity for soot combustion. The corresponding T10, T50, and T90 were 283 °C, 368 °C, and 420 °C, respectively, and the CO2 selectivity was 99.6%. The soot combustion activation energy for the SmMn2O5-EG&M catalyst is 65 kJ mol−1. O2-TPD and H2-TPR measurements demonstrated higher mobility and better reducibility of surface adsorbed oxygen for the EG&M sample. The soot combustion is greatly accelerated by the NO2-assisted mechanism under a NO + O2 atmosphere and further enhanced by the interconnected macropores of the catalyst, facilitating an intimate contact between the soot and the catalyst. Our study reveals that SmMn2O5 mullite is an effective catalyst for NOx-assisted soot combustion.