NaY分子筛担载FeSO4催化剂用于氨气还原NOx的性能  

Capability of molecular sieve-supported FeSO_4 catalyst for selective catalytic reduction of NO_x

作　　者：任雯[1] 赵博[1] 禚玉群[1] 陈昌和[1] 

机构地区：[1]清华大学热能工程系,热科学与动力工程教育部重点实验室,北京100084

出　　处：《化工学报》2011年第2期362-368,共7页CIESC Journal

基　　金：国家重点基础研究发展计划项目(2006CB200300)~~

摘　　要：研究了分子筛担载FeSO4催化剂在SCR脱硝反应中的催化性能和反应机理。实验结果表明,在同等工况下分子筛担载FeSO4后的催化剂具有更好的物理结构,与纯FeSO4相比脱硝率可提高将近20%。经Mossbauer谱分析,催化剂制备过程中Fe2+转化为Fe3+,其具体存在形式为Fe(OH)SO4与Fe2O(SO4)2,前者催化脱硝效果优于后者。原位红外分析结果表明,吸附在分子筛担载催化剂表面的氨与气相中的NO反应,Fe离子是吸附及发生催化氧化还原反应的活性中心。与钒、钛系SCR催化剂相比,所制备的催化剂不但具有廉价、高效的优点,而且能适应更高的反应空速,具有良好的工业应用前景。This paper focuses on the NO reduction by ammonia via FeSO4 catalyst supported by molecular sieve in a fixed bed reactor at 400℃.The experimental results indicate that the catalyst has immediate catalytic effect on NO reduction.Due to its improved physical structure,the catalyst improves the NO reduction rate by 20% compared with pure FeSO4.The effects of preparation conditions on catalytic activity,including the mix ratio,impregnation agent and impregnation time etc.,are investigated.Mossbauer spectroscopy is used for the study.It is found that Fe2＋ is oxidized to Fe3＋ during the preparation and most FeSO4 is transferred to Fe（OH）SO4 and Fe2O（SO4）2.Fe（OH）SO4 is better than the other speices in NO reduction and the ratio of different species is related to the water and oxygen content in atmosphere.The results of in-situ FTIR indicate that Fe is the reaction centre.NH3 is absorbed on the catalyst and reacts with NO,which can be explained by Eley-Rideal mechanism.Compared with other commercial catalysts,FeSO4 demonstrates great industrial potentials because of its low cost and excellent catalytic effect at high space velocity.

关 键 词：脱硝 选择性催化还原 分子筛 FeSO4催化剂 空速 

分 类 号：TQ032[化学工程]