铈改性的铜/六方介孔二氧化硅催化剂在温和反应条件下高效地将草酸二甲酯氢化为乙二醇

Cerium-modified copper/hexagonal mesoporous silica catalyst for efficient dimethyl oxalate hydrogenation to ethylene glycol under moderate reaction conditions

采用蒸氨法制备了一种高效的铈改性铜/六方介孔二氧化硅(xCe-Cu/HMS)催化剂,用于草酸二甲酯(DMO)气相化学选择性氢化成乙二醇(EG)。铈助剂可以显著提高催化剂的性能,在引入1.2%的铈后,催化剂的性能最好。在温和的条件下(200℃,2.0 MPa,H_(2)/DMO=100,LHSV_(DMO)=1.2 h^(−1)),DMO转化率和EG选择性分别达到了99.6%和96.3%。表征结果显示,Ce修饰的Cu/HMS可以增强Cu与载体之间的相互作用,改善Cu的分散性,并保持适当的Cu^(+)/(Cu^(+)+Cu^(0))的比例。本研究采用简单、低成本的路线,合成了具有优良催化性能的Ce改性的Cu-HMS催化剂,实现了在温和的条件下DMO向EG的高选择性转化。

A highly efficient cerium-modified Cu/hexagonal mesoporous silica(xCe-Cu/HMS)catalyst for the vapor-phase hydrogenation of dimethyl oxalate(DMO)into ethylene glycol(EG)was prepared using an ammonia evaporation method.The Ce promoter can significantly improve the performance of the catalyst,and the best catalytic performance was obtained after the introduction of 1.2%Ce promoter on Cu/HMS.The DMO conversion and EG selectivity got to 99.6%and 96.3%,respectively,under moderate conditions(200℃,2.0 MPa,H_(2)/DMO=100 and LHSV_(DMO)=1.2 h^(−1)).Characterization results revealed that Ce modification can enhance the interaction between Cu and the support,improve the dispersion of Cu on HMS,and maintain the appropriate ratio of Cu^(+)/(Cu^(+)+Cu^(0)).In this study,a simple and low-cost method was used to synthesize Ce-modified Cu-HMS catalysts,which showed excellent catalytic performance in conversion of DMO to EG under moderate conditions.