金属改性Pd/Al2O3对煤矿乏风催化氧化性能的影响

以堇青石蜂窝陶瓷为基体的Pd/Al2O3催化剂,通过负载不同金属(M:Ce、Ni、Ba、Mg、Fe、La和Mn)氧化物进行改性,研究煤矿乏风中甲烷的催化氧化反应机理。结果表明,不同金属氧化物负载下M-Pd/Al2O3晶相存在明显差异,Ni和Mg的负载阻止了Al2O3高温下向稳定的α-Al2O3相态转变,Ni和Mg添加与Al2O3形成NiAl2O4和MgAl2O4能有效地提高催化剂的低温催化活性和高温热稳定性；PdO2比PdO催化活性更高,Ni和Mg的负载能维持PdO2相态存在,减弱PdO2烧结发生和促进Pd的均匀分布；Ni、Mg氧化物改性Pd/Al2O3催化剂催化氧化煤矿乏风,具有良好的应用前景。

Effect of Pd/Al2O3 modification by metal on performance of ventilation air methane catalytic oxidation

Pd/Al2O3 catalysts deposited on cordierite-based ceramic honeycomb were prepared and tested for catalytic oxidation of ventilation air methane by addition of different metal(M:Ce, Ni, Ba, Mg, Fe, La and Mn) oxides. The results show crystalline difference among M-Pd/Al2O3 catalysts doped by various metal oxides in which Ni and Mg inhibit the transformation of Al2O3 towards α-Al2O3. The formation of NiAl2O4 and MgAl2O4 by addition of Ni and Mg effectively improved the activity at lower temperature and the thermal stability of catalysts. PdO2 has better catalytic activity than PdO. The addition of Ni and Mg could sustain more Pd in the phase of PdO2, suppress PdO particles aggregation and promote the distribution of Pd. The Pd/Al2O3 catalysts modified by Ni and Mg oxides may have promising prospects in VAM catalytic combustion.