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通过添加Pt-Ce作为助剂,对Al2O3担载的Cu催化剂进行修饰,制备负载型催化剂用于苯的催化氧化。利用XRD,N2吸附和H2-TPR等手段对载体和催化剂的织构-结构、活性组分的分散、还原性能及活性组分之间的相互作用进行了表征和分析。结果表明:添加Pt与Ce有利于提高CuO颗粒在Al2O3表面上的分散度,使其晶粒变小,从而改善了催化剂的性能。部分活性组分进入到Al2O3孔道中,在孔中及表面均形成了活性氧化物种。添加微量的Pt(0.1%(质量分数))及Ce可明显提高Cu/Al2O3催化剂的氧化活性,其中0.1%Pt/10%CuCe(12∶1)/Al2O3在250℃下就能完全催化氧化苯,表现出最佳的催化活性,可与贵金属催化剂(通常负载量在0.3%～2.0%)的活性相媲美。催化剂的高活性主要是在于活性组分在Al2O3表面的高分散以及PtOx,CuO和CeO2之间的相互作用。
By adding Pt-Ce as a promoter, the Al2O3 supported Cu catalyst was modified to prepare a supported catalyst for the catalytic oxidation of benzene. The structure and structure of the catalyst and catalyst were investigated by XRD, N2 adsorption and H2-TPR. The dispersion and reduction of the active components and the interaction between the active components were characterized and analyzed. The results show that addition of Pt and Ce can improve the dispersion of CuO particles on the surface of Al2O3 and make the grains smaller and improve the performance of the catalyst. Part of the active component into the Al2O3 channel, in the hole and the surface of the formation of reactive oxygen species. Adding trace amount of Pt (0.1% (mass fraction)) and Ce can obviously improve the oxidation activity of Cu / Al2O3 catalyst, of which 0.1% Pt / 10% CuCe (12:1) , Showing the best catalytic activity comparable to the activity of noble metal catalysts (usually with a loading of 0.3-2.0%). The high activity of the catalyst is mainly due to the high dispersion of the active component on the surface of the Al 2 O 3 and the interaction between PtOx, CuO and CeO 2.