Abstract
Crystalline Mo-V-Cu oxides with orthorhombic and trigonal structure (Orth-MoVCuO and Tri-MoVCuO) could be firstly synthesized by using structure directing agent in a hydrothermal synthesis and their catalytic activity for the selective oxidation of acrloein was evaluated with crystalline Mo-V oxides with the same crystal structure (Orth-MoVO and Tri-MoVO). Detail characterizations indicated that structural frameworks of Orth-MoVCuO and Tri-MoVCuO are comprised by Mo and V and Cu is introduced inside the heptagonal channel in the crystal structure. In the selective oxidation of acrolein, even though the acrolein conversion was considerably decreased by the introduction of Cu, the selectivity to acrylic acid was significantly improved. In addition, the activity decrease with reaction time observed in Orth-MoVO and Tri-MoVO became moderate by the introduction of Cu. In the TPR and TPO analyses, we found that the introduction of Cu significantly enhanced the reduction-oxidation rates which might enable the dynamic redox changes during the reaction, leading to the improved durability of the acrylic acid selectivity with the reaction time. In the presentation, we will discuss about the synthesis method, crystal structure and the role of Cu for the selective oxidation of acrolein.
