锰钛系低温选择性催化还原催化剂的抗SO2和抗H2O性能研究进展

摘要

低温选择性催化还原(SCR)脱硝技术具有运行成本低、能耗低和布置方便的优点,催化剂的反应温度低,适合中小型工业锅炉的脱硝技术需求,因此受到越来越多的关注.锰钛系催化剂以其较高的低温脱硝效率成为当前低温SCR催化剂研究领域的热点,然而催化剂易受到SO2和H2O的影响,限制了它的工业应用.本文介绍了在含SO2和H2O的条件下锰钛系低温SCR催化剂的中毒症状,总结了催化剂的SO2和H2O中毒机制,重点阐述了在抗硫方面掺杂过渡金属元素以及载体改性的研究进展,详细介绍了掺杂Ce、Co、Fe和Ho等元素以及催化剂酸改性和复合载体对催化剂抗硫性的影响,同时简要总结了近年来其他方法提高锰钛系低温SCR催化剂抗硫抗水性能的状况,最后归纳了目前此类催化剂抗硫抗水措施的局限并指出今后的重点是进一步提高其抗中毒能力.%Low temperature SCR denitration technology has the advantages of low cost,low energy consumption and convenient layout. The reaction temperature of the catalysts is low,which is suitable for small and medium-sized boilers,therefore it has attracted more and more researchers' attentions. Manganese-titanium based catalysts have become a hotspot in the research of low-temperature SCR catalysts due to their excellent catalytic activity. However,the poor sulfur and water resistance of the catalysts limits their practical application. This study mainly introduces the symptoms and mechanism of SO2and H2O poisoning of manganese-titanium catalysts for low temperature SCR. The research progress of doping transition metal elements and modification of the carrier in the aspect of sulfur resistance is mainly discussed. The effects of doping Ce,Co,Fe and Ho,as well as the acid modification of catalysts and compound carrier are introduced in detail. In addition,the recent situation of other modification methods of manganese-titanium catalysts are briefly introduced. Finally,the limitations of the present methods of the sulfur and water resistance for SCR catalysts are summarized,and we point out that the future focus of this kind of catalysts is to further improve their anti-poisoning ability.