固体炭对一氧化氮低温催化解离还原反应的影响——Ⅰ.复合催化剂还原活性的考察

STUDY ON THE CATALYTIC REDUCTION OF NO BY CARBON Ⅰ. ACTIVITY OF THE COMPOSITE CATALYSTS

考察了担载在活性炭上的以铜、铁为主的复合催化剂对一氧化氮催化解离还原活性的影响,并通过TPR和XRD研究了不同金属组份配比和不同助剂(K、Na)对催化剂性能的影响。结果表明,通过选择不同催化剂配比和添加不同助剂,降低主催化剂在载体炭上的还原温度和提高主催化剂在载体炭上的分散度,将有利于提高催化剂对一氧化氮催化解离还原的活性。文中还采用电镜方法研究了不同组成复合催化剂的金属颗粒大小和Cu、Fe复合催化剂经反应后其表面的形貌结构,发现在这种炭载型复合催化剂上进行一氧化氮催化解离还原反应的过程中,有催化剂表面金属颗粒迁移、生成炭丝和金属颗粒在载体炭上打洞等迹象。

The reduction of NO by carbon was carried out in the presence of Fe-Cu catalysts. The effects of the contents of Fe and Cu on the activity were studied by using TPR and XRD. Potassium and Na promopted Fe-Cu catalysts were also characterized. The results have shown that lower reduction temperature and higher dispersion of Fe and Cu are favourable to increasing the activity of the composite catalysts. This can be realised by selecting the suitable ratio of Fe to Cu and adding K or Na as a promotor, TEM was utilized to investigate the particle size of various catalysts and the topography of the catalysts surface after reaction. The migration of metal particles on the surface of carbon and the growth of filamentous carbon and the production of channel were observed during the reduction of NO, catalyzed by the composite catalysts.