Cu-Ni双金属催化剂上CO_2的加氢反应

Hydrogenation of CO_2 over Cu-Ni/Al_2O_3 Bimetallic Catalysts

采用真空浸渍法 ,制备了 Cu- Ni双金属催化剂 (引入 Cu前 ,Ni以不同的状态存在 ) ,在连续流动微型反应装置上测试了各催化剂上的 CO2 加氢性能 ,并用 XRD方法对催化剂进行了表征 .实验发现 ,与 Cu/Al2 O3催化剂相比 ,Cu- Ni/Al2 O3催化剂上 CO2 逆变换反应的活性因 Ni的存在而受到抑制 . Cu引入前处于氧化态的 Ni,对所制得的 Cu- Ni催化剂上 CO生成的抑制更为明显 . Cu- Ni/Al2 O3双金属催化剂表现出 CO2 甲烷化的催化活性 ,用引入 Cu前处于还原态的 Ni制备的双金属催化剂 ,更有利于

Cu Ni/Al 2O 3 bimetallic catalysts were prepared by vacuum impregnation. Catalysts with different chemical states of Ni before the Cu impregnation were investigated by CO 2 hydrogenation activity measurement and XRD characterization. It is found that as compared with Cu/Al 2O 3 catalysts the activity of reverse transform reaction of CO 2 on Cu Ni/Al 2O 3 is suppressed by the presence of Ni. This suppressing effect is more obvious if Ni is in the oxidized state before the Cu impregnation than if Ni is in the reduced state. Cu Ni/Al 2O 3 bimetallic catalysts exhibit methanation activity but Cu/Al 2O 3 catalysts do not. The methanation activity is higher when Ni is in the reduced state before the impregnation of Cu than when Ni is in the oxidized state.