铁基中低温scr脱硝催化剂性能研究 学位论文.doc

铁基中低温SCR脱硝催化剂性能研究 摘 要 氮氧化物(NOx)对人体、环境的危害很大，是目前国内外急需解决的问题之一。选择性催化还原法具有脱硝效率高、N2选择性好等优点，得到广泛使用。商业化的脱硝催化剂铁的氧化物环境友好、价格低廉还原性，受到了国内外学者的关注。本文主要针对脱硝催化剂的制备、表征等各方面进行了。 本文、因素对催化剂性能的影响。XRD、X、H-TPR、BET比表面积测试、等表征催化剂进行了表征，并且催化剂的脱硝活性。XRD、X、BET比表面积测试表征TiO2为载体，Fe2O3为活性组分制备了负载型脱硝催化剂。考察了XO及不同助剂对SCR催化活性的影响。利用XRD、H-TPR、BET比表面积测试催化剂具有更强的性，促进催化剂脱硝活性的；的活性温区宽，并且脱硝活性Fe、Si、Al等多种元素，颗粒表面存在Si、Na、Al、V等元素的富集。多元金属氧化物比表面积极低，基础脱硝活性较低，不适合直接作为脱硝催化剂或者活性组分。 制备了XO为催化剂基体，TiO2为载体，Fe2O3为活性组分的催化剂，考察基体对催化剂的影响。实验结果表明，加入多元金属氧化物后，催化剂比表面积减小、氧化性增强。在250 ℃-350 ℃内催化剂的脱硝活性在90 %以上，但是活性温窗较窄。分别使用CeO2、MoO3、WO3对催化剂进行掺杂，实验结果表明：掺杂后催化剂比表面积增大，有利于氨气的吸附，促进SCR反应的进行；CeO2掺杂后催化剂的脱硝活性在整体上提高，但是最佳活性温窗没有变宽或者变化；MoO3、WO3掺杂后催化剂的中低温活性降低，高温活性提高，活性温窗宽，并向高温移动。 关键词：ABSTRACT In recent years, with the rapid development of industrialization in China, atmospheric pollution caused by the burning of fossil fuels has being more and more serious. NOx is one of the main atmospheric pollutants, which bring huge harm to human body and environment, it is one of the urgent problems at home and abroad to be solved. There are many methods controlling NOx emission，one of the most widely used is selective catalytic reduction (SCR), it has advantages of high denitration efficiency and N2 selectivity. At present, there exist some problems in the commercial catalyst, the price is expensive, narrow active temperature window, and abandoned catalyst will lead to secondary pollution. So, it has very important significance to develop environmental friendly catalyst, low temperature, high efficiency and cheap. Iron oxide, has received the attention of scholars both at home and abroad, because it has advantages of environmentally friendly, low prices,and strong reducibility. This paper focuses on the preparation and characterization of denitration catalyst based on Fe. First, a series of experiments were conducted to research denitration catalyst based on Fe, including the preparation method and the content of CeO2. The catalysts were characterized with XRD, XPS, H