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采用ＣＯ和ＣＯ＿２对比加氢活性测试，ＸＲＤ及ＴＰＲ方法研究了两个不同Ｎａ助剂含量的低镍Ｎｉ／Ａｌ＿２Ｏ＿３体系的性能。实验发现，在低镍催化剂上ＣＯ＿２在较低温度下就可加氢生成甲烷，而ＣＯ则需要更高的温度，ＣＯ＿２无需先经逆变换生成ＣＯ，然后再加氢，它可直接加氢生成ＣＨ＿４。在同一催化剂上，ＣＯ＿２加氢生成ＣＨ＿４的表现活化能要低于ＣＯ加氢生成ＣＨ＿４反应的表现活化能。晶相ＮｉＯ还原后形成的活性相对ＣＯ＿２加氢反应的活性明显高于它对ＣＯ的加氢活性，非晶相镍氧化物还原后形成的活性相对ＣＯ的加氢反应特别有利。Ｎａ助剂的含量不同会造成Ｎｉ氧化物物种的分配不同，从而导致ＣＯ、ＣＯ＿２的加氢活性及其随温度的变化也不相同，催化剂对ＣＯ、ＣＯ＿２加氢反应作用的本质是不相同的。
The performance of low nickel Ni / Al 2 O 3 system with two different Na additives was studied by CO and CO 2 contrast hydrogenation tests, XRD and TPR methods. It was found that CO 2 can be hydrogenated to methane at a lower temperature on low nickel catalysts, while CO requires higher temperatures. CO 2 does not need to undergo inverse transformation to generate CO and then hydrogenates, which can be directly hydrogenated CH_4. On the same catalyst, the activation energy for the hydrogenation of CO_2 to CH_4 is lower than the activation energy for CO_2 hydrogenation to CH_4 reaction. The activity of NiO formed after the reduction of the crystalline phase is significantly higher than that of the hydrogenation of CO over the hydrogenation of CO, and the hydrogenation of the Ni-based amorphous oxide after reduction is particularly beneficial to the hydrogenation of CO. The different contents of Na promoters lead to different distribution of Ni oxides species, resulting in different hydrogenation activities of CO and CO 2 and their changes with temperature. The nature of the catalysts for the CO and CO 2 hydrogenation reactions is not the same .