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以介孔分子筛KIT-6为模板,通过硬模板法制得了具有高比表面积、有序介孔结构的CuFe2O4尖晶石型复合氧化物.采用X射线衍射(XRD)、N2-吸/脱附、H2-程序升温还原(H2-TPR)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、X射线荧光光谱分析(XRF)及X射线光电子能谱(XPS)对硬模板和硬模板法制备的介孔CuFe2O4及传统溶胶-凝胶法制备的CuFe2O4进行了表征.结果表明,硬模板KIT-6结晶良好,介孔结构规整统一,孔径最可几分布在9.1 nm,适合CuFe2O4前驱体的填充.以KIT-6为模板制得的介孔CuFe2O4孔径较小(约4.3 nm),介孔结构明显,比表面积高达194 m2/g.此外,以选择性催化氧化NH3为探针反应,考察了介孔CuFe2O4的催化活性,结果显示,该催化剂选择性催化氧化NH3性能良好,300℃时NH3转化率接近100%,此时,N2选择性高达96%,随着温度升高,N2选择性依然维持在较高水平,600℃时,N2选择性在80%以上.
The CuFe2O4 spinel composite oxide with high specific surface area and ordered mesoporous structure was prepared by hard template method using mesoporous molecular sieve KIT-6 as a template. X-ray diffraction (XRD), N2-adsorption / desorption, H2-TPR, TEM, X-ray fluorescence (XRF) and X-ray photoelectron spectroscopy (XPS) were used to prepare hard template and hard template Mesoporous CuFe2O4 and CuFe2O4 prepared by the conventional sol-gel method were characterized.The results show that the crystal structure of KIT-6 is well crystallized and the mesoporous structure is uniform and the pore size is most distributed at 9.1 nm, which is suitable for the filling of CuFe2O4 precursor The pore size of mesoporous CuFe2O4 with KIT-6 as a template is small (about 4.3 nm), and the mesoporous structure is obvious with a specific surface area as high as 194 m2 / g.In addition, selective catalytic oxidation of NH3 with a probe reaction The catalytic activity of the mesoporous CuFe2O4 was investigated. The results showed that the catalyst selectively catalyzed the oxidation of NH3. The conversion of NH3 was close to 100% at 300 ℃. At this time, the N2 selectivity was as high as 96%. With the increase of temperature, Maintained at a high level, 600 ℃, N2 selectivity in more than 80%.