用高锰酸钾和硫酸锰在酸性条件下合成的八面体锰分子筛载体(OMS-2)为载体,采用沉积沉淀、浸渍还原、原位合成三种方法制备了OMS-2负载的纳米金催化剂,并进行了X射线衍射(XRD)和透射电镜(TEM)表征.以分子氧为氧化剂,考察了不同反应条件下纳米金催化剂在无溶剂体系中环己烯液相氧化的催化性能.结果表明,沉积沉淀法制备的纳米金催化剂显示出较佳的催化活性,该催化剂在80℃、0.5 MPa、24 h反应条件下,环己烯氧化转化率为39.9％,环己烯醇和环己烯酮的选择性分别为35.5％和51.9％.%The manganese oxide octahedral molecular sieves (OMS-2) were synthesized by potassium permanganate and manganese sulphate under acidic condition, and the prepared OMS-2 were used as the support for the preparation of a series of supported nano gold catalysts Au/OMS-2 by one-pot method, impregnation-reduction (IMP) method and deposition-precipitation (DP) method, separately. The prepared catalysts were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM), respectively. In a solvent-free cyclohexene oxidation system using oxygen as the oxidant, the catalytic performances of the prepared catalysts under different reaction conditions were investigated. The results show that, under the reaction conditions of 80℃, 0.5 Mpa and 12 h, the catalytic performance of nano gold catalysts prepared by DP method is better, and the cyclohexene conversion ratio of 39.9%, selectivity to 2-cyclohexene-l-ol of 35.5% and to 2-cyclohexene-l-one of 51.9% can be achieved respectively.
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