铁基催化剂选择性催化还原烟气脱硝特性比较研究

Comparison About Selective Catalytic Reduction of De-NO_x on Iron-based Magnetic Materials

以铁及铁的氧化物为床料,研究了不同催化剂对脱除烟气中氮氧化物效率的影响。实验中分别采用Fe和Fe2O3的混合物、纯Fe2O3及Fe3O4作为催化剂,研究在中低温的范围内烟气脱硝效果。结果表明,铁氧化物对选择性催化还原脱硝均有作用,但Fe2O3的活性更强,脱硝效果更大,在250℃时得到最高为91%的转化率。同时对催化剂进行了X射线衍射分析,初步确定反应的物相,M?ssbauer光谱分析则进一步确定催化剂所处的环境,结果表明两者的分析一致,γ-Fe2O3在选择性催化还原反应中起决定性的作用。

Elementary studies of different catalysts on the fluidized bed have been done on the selective catalytic reduction （SCR） based on iron and iron oxides. Under different temperatures and catalysts, there were distinct conversions. The study compared the conversion of Fe, Fe203 and Fe304 in some specifical range of temperature. The result indicated that iron oxides had the active of de-NOx, especially the maghemite, the conversion of NOx on the maghemite reaches 91% at 250℃. During the experiment, X-ray diffraction （XRD） was done to decide the phases of catalysts, at the same time, Mrssbauer spectroscopy was used to further determine the environment that catalysts existed. The results showed that both the analysis was consistent, γ-Fe2O3 played the main effect in SCR.