MnO_(x)-ZSM-5脱硝催化剂制备的溶剂效应研究  

Study on solvent effect on preparation of MnO_(x)-ZSM-5 deNOx catalysts

作　　者：周微 张耿睿 于海斌 马新宾[1] 刘飞[4] 刘家旭 ZHOU Wei;ZHANG Gengrui;YU Haibin;MA Xinbin;LIU Fei;LIU Jiaxu(Institute of Chemical Engineering,Tianjin University,Tianjin 300350,China;Center Tech Tianjin Chemical Research and Design Institute Co.Ltd.;Institute of Chemical Engineering,Dalian University of Technology;Lanzhou Petrochemical Research Center,PetroChina)

机构地区：[1]天津大学化工学院,天津300350 [2]中海油天津化工研究设计院有限公司 [3]大连理工大学化工学院 [4]中国石油兰州化工研究中心

出　　处：《无机盐工业》2022年第8期138-144,共7页Inorganic Chemicals Industry

摘　　要：MnO_(x)-ZSM-5脱硝催化剂具有较好的低温氨选择性催化还原反应(NH_(3)-SCR)活性,因其原料成本低、脱硝效率高等优点成为研究热点。详细叙述了采用蒸干溶剂法、通过调变制备过程中溶剂组成(乙醇和水或其混合溶液)制备系列MnO_(x)-ZSM-5催化剂,并首次研究了“溶剂效应”对催化剂脱硝性能产生影响的原因。利用X射线衍射(XRD)、光电子能谱仪(XPS)、程序升温氨吸附法(NH_(3)-TPD)、N_(2)物理吸附、氢气程序升温还原(H_(2)-TPR)以及扫描电子显微镜(SEM)等表征手段分析了催化剂物化性质、锰存在状态与催化性能之间的相互关系。结果发现,随着溶剂中水分占比的提高,MnO_(x)-ZSM-5脱硝催化剂的比表面积降低,具有高催化活性的Mn^(4+)物种比例迅速下降,这些原因均导致催化剂的脱硝活性逐步降低。说明溶剂组成会影响催化剂的脱硝性能,因此在制备MnO_(x)-ZSM-5脱硝催化剂时选取合适的溶剂是至关重要的,这为如何制备高活性的MnO_(x)-ZSM-5脱硝催化剂提供了重要信息。MnO_(x)-ZSM-5 deNOx catalyst has good low⁃temperature NH_(3)-SCR activity.It has become a research hotspot be⁃cause of the low raw material cost and high deNOx efficiency.A series of MnO_(x)-ZSM-5 catalysts prepared by adjusting the composition of solvents(ethanol,water or their mixed solutions)with steam dry solvent method was described in detail.The reason of influence of“solvent effect”on the deNOx performance of catalysts was studied for the first time.X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),temperature programmed ammonia adsorption(NH_(3)-TPD),N_(2) physical adsorption,hydrogen temperature programmed reduction(H_(2)-TPR)and scanning electron microscopy(SEM)were used to analyze the relationship between the physical and chemical properties of the catalyst,the existing state of manganese and the catalytic performance.The results showed that the specific surface area of MnO_(x)-ZSM-5 deNOx catalyst decreased,and the proportion of Mn^(4+)species with high catalytic activity decreased rapidly with increasing the proportion of water in the solvent,resulting in the gradual decrease of the deNOx activity of the catalyst,which indicated that the solvent composition affected the deNOx performance of the catalyst.Therefore,it was very important to select an appropriate solvent in the prepa⁃ration of MnO_(x)-ZSM-5 deNOx catalyst,which provided important information on how to prepare high activity MnO_(x)-ZSM-5 deNOx catalyst.

关 键 词：MnO_(x)-ZSM-5 脱硝催化剂 氨选择性催化还原反应 蒸干溶剂法 溶剂效应 

分 类 号：TQ137.1[化学工程—无机化工]