摘要
用共沉淀法制备了一组Mg-Fe复合氧化物催化剂,用于N2O催化分解,考察了催化剂组成、焙烧温度、负载助剂钾等参数对其催化活性的影响。采用N2物理吸附、X射线衍射、H2-程序升温还原等技术对催化剂进行了结构表征。结果表明,500℃焙烧的Mg0.6Fe0.4Fe2O4催化剂对于N2O分解反应有较高活性,而K改性的催化剂活性均有所降低,且K的负载量越高,改性催化剂的活性越低,这是由于负载的K粒子抑制了表面铁物种的还原,降低了催化剂的比表面积。在有氧无水、水氧共存条件下连续反应10h,Mg0.6Fe0.4Fe2O4的催化活性和稳定性均显著高于FeOx催化剂。
A series of Mgx Fe1-x Fe2 O4 spinel oxides were prepared and characterized by means of nitrogen physisorption, X-ray diffraction （ XRD ） and temperature-programmed reduction of hydrogen （ H2-TPR ） . The effect of composition, calcination temperature, and potassium doping on the catalytic activity of the Mg-Fe mixed oxides in N2 O decomposition was investigated.The results indicated that the Mg0.6 Fe0.4 Fe2 O4 catalyst calcined at 500℃exhibits highest activity in N2 O decomposition.Unexpectedly, the catalyst activity is depressed by the addition of potassium, as the potassium doping may inhibit the reduction of surface iron oxides and reduce the surface area of K-modified catalysts.Long-term tests at 500℃for 10 h also illustrate that Mg0.6 Fe0.4 Fe2 O4 is superior to FeOx catalyst eti her in the oxygen-alone or in the oxygen-steam concomi tant atmosphere.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2014年第12期1464-1469,共6页
Journal of Fuel Chemistry and Technology
基金
Supported by the Research Project from Department of Science and Technology of Shandong Province(2012GSF11708)
