MCM-41负载纳米钯催化剂制备及其催化脱氢性能的研究

Preparation of MCM-41 Supported Nano-palladium Catalysts and Its Catalytic Dehydrogenation Performance

采用湿法浸渍-辉光放电等离子还原法,制备了MCM-41负载纳米钯催化剂(Pd-WP/M41),并通过XRD、TEM、XPS、H2-TPR和H2-TPD等手段对Pd-WP/M41进行了表征。结果表明:钯纳米粒子(PdNPs)均匀分散在载体MCM-41表面,平均粒径为2.52 nm。与化学还原法制备的催化剂(Pd-WC/M41)相比,Pd-WP/M41上钯的分散度更高,且具有更多的催化活性位点。Pd-WP/M41催化十二氢-N-乙基咔唑(12H-NEC)的脱氢反应实验结果表明,在180℃下反应6 h时,12H-NEC脱氢效率为98.79%,脱氢反应活化能为85.2 k J/mol。Pd-WP/M41循环4次时,12H-NEC脱氢效率仍达到91.23%。

MCM-41 supported nano palladium catalysts(Pd-WP/M41)are prepared by wet impregnation-glow discharge plasma reduction method,and characterized by XRD,TEM,XPS,H2-TPR and H2-TPD.The results show that the Pd nanoparticles(PdNPs)are uniformly dispersed on the surface of MCM-41 with an average particle size of 2.52 nm.Compared with the catalyst prepared by chemical reduction method(Pd-WC/M41),the Pd-WP/M41 has higher dispersion of palladium and more catalytic active sites.The experimental results of the dehydrogenation of 12H-NEC cat-alyzed by Pd-WP/M41 show that the dehydrogenation efficiency of 12H-NEC is 98.79%at 180℃for 6 h and the activation energy of the dehydrogenation reaction is 85.2 kJ/mol.After 4 cycles of Pd-WP/M41,the dehydrogenation efficiency of 12H-NEC still reaches 91.23%.