采用原位合成法制备出Au/SBA-15催化剂,用沉积-沉淀方法制备出Au-Ni/SBA-15、Au-Co/SBA-15催化剂,通过XRD、TEM-EDS等手段对晶体结构和金属分散度进行表征。在没有任何有机溶剂或助剂的条件下,以空气为氧化剂做环己烷选择性氧化,并用该反应对催化剂催化性能进行评价。结果表明,双金属催化剂对选择氧化环己烷制备环己酮和环己醇表现了良好的协同作用,可以大大增加催化剂的活性。以Au-Co/SBA-15为催化剂,反应压力3 MPa,反应温度为423 K,反应时间2 h时,环己烷的转化率为22.1%,环己醇和环己酮的总选择性为95.1%。
Au/SBA-15,Au-Ni/SBA-15,Au-Co/SBA-15 catalyst were prepared by in situ synthesis and deposition synthesis,and the crystal structure and metal dispersion were characterized by XRD,TEM-EDS and other means.In the condition of absence of any organic solvents or additives,air was used as the oxidant to oxidize cyclohexane selectively,and catalytic properties were evaluated in this reaction.It is found that good synergistic effect exists in the two-metal catalysts for selective oxidation of cyclohexane to cyclohexanone and cyclohexanol,which can greatly increase the catalytic activity.The conversion rate of cyclohexane is 22.1%,and the total selectivity of cyclohexanol and cyclohexanone is 95.1%,when Au-Co/SBA-15 was used as the catalyst in the condition of 3 MPa,423 K and 2 hours.