Selective catalytic oxidation of ammonia to nitrogen over orderly mesoporous CuFe_2O_4 with high specific surface area  

作　　者：Wenrui Yue Runduo Zhang Ning Liu Biaohua Chen 

机构地区：[1]State Key Laboratory of Chemical Resource Engineering,Beijing University of Chemical Technology

出　　处：《Chinese Science Bulletin》2014年第31期3980-3986,共7页

基　　金：supported by the National High Technology Research and Development Program of China (2013AA065900);the National Natural Science Foundation of China (21177008,21121064)

摘　　要：Orderly mesoporous CuFe2O4spinel-type mixed oxide with high specific surface area was prepared successfully by a hard-template method in which KIT-6mesoporous silica was selected as the hard template.The KIT-6 hard template and CuFe2O4samples were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,X-ray fluorescence,transmission electron microscopy,scanning electron microscopy,nitrogen physisorption,and hydrogen-temperature programmed reduction.The KIT-6 hard template had perfect crystallization and ordered mesoporous structure with a probable pore distribution of about 9.1 nm,large enough to be filled by the spinel precursor.The mesoporous CuFe2O4spinel oxide synthesized inside the KIT-6 mesopores had a relatively small pore size(4.3 nm),orderly arrangement,and high specific area(194 m2/g).The catalytic activity of the mesoporous CuFe2O4was tested for the selective oxidation of ammonia to nitrogen.The conversion of ammonia reached nearly 100%at 300°C with a nitrogen selectivity as high as 96%.The nitrogen selectivity remained high with increasing temperature and even maintained a value of80%at 600°C.Orderly mesoporous CuFe2O4 spinel-type mixed oxide with high specific surface area was prepared successfully by a hard-template method in which KIT-6 mesoporous silica was selected as the hard template. The KIT-6 hard template and CuFe2O4 samples were charac- terized by X-ray diffraction, X-ray photoelectron spec- troscopy, X-ray fluorescence, transmission electron microscopy, scanning electron microscopy, nitrogen physisorption, and hydrogen-temperature programmed reduction. The KIT-6 hard template had perfect crystalli- zation and ordered mesoporous structure with a probable pore distribution of about 9.1 nm, large enough to be filled by the spinel precursor. The mesoporous CuFe2O4 spinel oxide synthesized inside the KIT-6 mesopores had a rela- tively small pore size （4.3 nm）, orderly arrangement, and high specific area （194 m2/g）. The catalytic activity of the mesoporous CuFe2O4 was tested for the selective oxidation of ammonia to nitrogen. The conversion of ammonia reached nearly 100 % at 300 ℃with a nitrogen selectivity as high as 96 %. The nitrogen selectivity remained high with increasing temperature and even maintained a value of 80 % at 600 ℃.

关 键 词：高比表面积 选择性催化氧化 有序 中孔 X射线光电子光谱学 透射电子显微镜 扫描电子显微镜 氮 

分 类 号：O643.36[理学—物理化学]