铁铈复合氧化物催化剂的制备及其性能研究∗

摘要

采用改进共沉淀法制备铁铈复合氧化物催化剂,通过 L16(45)正交实验确定最佳工艺条件.研究了不同煅烧温度对催化剂脱硝效率的影响,同时通过XRD、SEM、粒度和比表面积等方法对催化剂进行表征.结果表明,反应终点pH 值是碳酸氢铵-氨水沉淀法制备铁铈催化剂最重要的影响因素,反应温度次之.脱硝实验表明,经400℃焙烧5 h所制备的催化剂,其粒径较小,分布较宽,比表面积较大,SCR 脱硝活性最高,在250℃脱硝活性为93．8％.%The preparation process of catalyst composited with Fe-Ce oxides was studied by improved co-precipi-tation.The optimum conditions were determined by L16 (45 )orthogonal test.The effects of different calcination temperature on SCR of Fe-Ce catalyst were studied,and also the materials were characterized by XRD,SEM, particle size and specific surface area.The results show that the final pH of the reaction is the most important factor for Fe-Ce catalyst precipited from bicarbonate-ammonia system.Reaction temperature is the secondary factor.The denitration experiments showed that catalyst prepared by roasting at 400 ℃ for 5 h with smaller particle size,wider distribution,larger specific surface area and the highest SCR denitration activity.The activi-ty was 9 3 .8% at 2 5 0 ℃.