MnOx-L负载Fe催化剂的制备及其催化氧化CO性能  

Preparation of Fe-doped Octahedral Layered Birnessites Catalysts and the Catalytic Oxidation of CO

作　　者：傅之丹[1] 付娇丽 叶青[1] 程水源[1] 康天放[1] FU Zhidan;FU Jiaoli;YE Qing;CHENG Shuiyuan;KANG Tianfang(Key Laboratory of Beijing on Regional Air Pollution Control,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学区域大气复合污染防治北京市重点实验室,北京100124

出　　处：《北京工业大学学报》2020年第4期360-368,共9页Journal of Beijing University of Technology

基　　金：国家自然科学基金资助项目(21277008,20777005);北京市自然科学基金资助项目(8082008);北京市教育委员会教师队伍建设—人才强教-14创新团队计划资助项目(IDHT20140504)。

摘　　要：为了有效去除大气污染物中的CO,使用氧化还原法制备层状锰氧化物MnOx-L,并用离子交换法制备了负载不同质量分数Fe的Fex/MnOx-L催化剂.使用扫描电子显微镜(scanning electron microscope,SEM)、X射线衍射(X-ray diffraction,XRD)技术、比表面积测定(brunauer emmett teller,BET)、热重分析(thermogravimetric analysis,TGA)、氢气程序升温还原(hydrogen temperature-programmed reduction,H2-TPR)、氧气程序升温脱附(oxygen temperature-programmed,O2-TPD)、X射线光电子能谱(X-ray photoelectron spectroscopy,XPS)等技术表征催化剂形貌、结构及性能.层状锰氧化物MnOx-L具有典型的八面体层状结构,Fe负载对催化剂结构影响不大,但对其理化性质产生了影响.Fe负载改变了催化剂的还原性及其表面的m(Fe^2+)/m(Fe^3+)和m(Oads)/m(Olatt)比例,提高了样品的催化活性.在所有Fex/MnOx-L样品中,Fe5/MnOx-L具有最高的低温还原性、氧移动性,m(Fe^2+)/m(Fe^3+)及表面吸附氧最高.催化氧化CO反应中,Fe5/MnOx-L具有最佳的催化活性(t 50=80℃和t 90=150℃),这与Fe和MnOx-L载体之间的相互作用有关.To effectively remove CO from atmospheric pollutants,the octahedral layered birnessites(MnOx-L)was prepared by a redox method,and Fex/MnOx-L samples with different mass fractions of Fe loading were prepared by ion exchange method.Physicochemical properties of the samples were characterized by scanning electron microscope(SEM),X-ray diffraction(XRD)technique,BET(specific surface area measurement),thermogravimetric analysis(TGA),hydrogen temperature programmed reduction(H 2-TPR),oxygen temperature-programmed desorption(O2-TPD),X-ray photoelectron spectroscopy(XPS)techniques.MnOx-L support was a typical octahedral birnessites structure.Fe loading did not affect the support structure,but influenced their physical and chemical properties.The reduction of the catalyst and the ratio of m(Fe^2+)/m(Fe^3+)and m(Oads)/m(Olatt)on the surface changed,as well as the catalytic activity significantly improved after loading iron.Among Fex/MnOx-L samples,Fe5/MnOx-L showed the best reducibility,oxygen mobility,and the highest ratio of m(Fe^2+)/m(Fe^3+)and surface adsorption oxygen.Fe5/MnOx-L showed the best catalytic activity(t 50=80℃and t 90=150℃)for CO oxidation,related to the interaction between Fe species and MnOx-L.

关 键 词：层状锰氧化物 Fex/MnOx-L 催化氧化CO 负载量 活性 还原性 

分 类 号：O643[理学—物理化学]