负载金属催化剂的褐煤活性半焦脱除烟气中NO性能及机理

NO removal with carbon catalyzed by activated-char-supported metals during flue gas cleaning

对负载金属催化剂的褐煤活性半焦脱除烟气中NO的性能进行了研究,并对其反应机理进行了探讨。使用自制的脱硝剂在固定床反应装置上进行了脱硝实验;使用红外光谱仪(FTIR)和X射线衍射仪(XRD)对脱硝剂脱硝前后的表面官能团及金属活性相进行了分析。结果表明,金属铜作为催化剂具有优于其他金属的脱硝性能;在铜基催化剂中添加铁作为助剂的活性半焦具有更优的脱硝性能,其有效脱硝质量可达8.70g(基于100g活性半焦);金属催化剂的低价态活性相具有较高的催化活性,随着脱硝反应的进行,金属活性相被氧化成为活性较低的高价态,最终完全失活;复合金属氧化物铁酸铜能起到活性相"存储"作用,在反应过程中分解成为活性更高的金属活性相,从而提高了脱硝性能。

In this paper,the removal of NO from flue gas by lignite activated char loaded metal catalyst was studied,and the reaction mechanism was discussed. Denitrification experiments were carried out using the homemade denitrification agent in a fixed bed reactor. The surface morphology,element distribution and metal phase form of the denitrification agent before and after the reaction were analyzed by using Fourier transform infrared（FTIR）and X ray diffraction（XRD）. The results show that copper has better denitrification performance than other metals and adding iron in copper based catalyst activated char improved its denitrification performance. The denitrification rate reached 8.70 g/（100 g activated char）. During the denitrification process,the catalysts gradually deactivated due to the oxidation of the active metal phases,while the composite metal oxide copper ferrite was decomposed into activated metal with higher activity phase,which improved the denitrification performance.