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制备了Ｃｕ－Ｚｎ－Ａｌ （４／５０／５）催化剂（Ｃａｔ）和Ｃｕ－Ｚｎ－Ａｌ－Ｌｉ（４０／５０／５／５）催化剂（Ｃａｔ－Ｌｉ）．并将其分别用于由ＣＯ／Ｈ_２和ＣＯ_２／Ｈ_２合成甲醇。诸如ＴＰＤ、ＴＰＲ、ＴＰＳＲ、脉冲、ＣＤ３Ｉ－捕获、同位素标记、ＥＰＲ及原位ＤＲＩＦＴ等技术和方法被用来表征这两种催化剂及研究反应机理，对处于去氢、含氢及含氧态催化剂进行了对比研究以期阐明表面氧和表面氢对ＣＯ_２和ＣＯ活化所起的作用。提出了一个由甲酸根和甲醛氢化及甲醇氧化结果为证的ＣＯ／ＣＯ_２氢化机理。由于通过Ｌｉ+取代ＣｕＯ晶格上的Ｃｕ２＋形成的氢空位，在Ｃａｔ中添加Ｌｉ＋改善了甲醇合成活性。ＣＯ_２能被一捕获的电子（Ｆ-中心）活化，生成的ＣＯ2-能容易地被氢化成甲酸根和亚甲基双草酰，后者分解生成Ｈ２ＣＯ和表面氧。ＣＯ能被表面氧活化，生成的ＣＯ２－将遵循ＣＯ_２氢化的途径。在ＣＤ３Ｉ－捕获的实验中，我们捕获了表面氧。在无表面氧时，ＣＯ可能直接氢化成甲酸基，即ＣＯ_２氢化中的一途径。由亚甲基双草酰产生的Ｈ２ＣＯ表面模型可能与由甲醛吸附或ＣＯ氢化生成的Ｈ２ＣＯ表面模型不同。
Cu-Zn-Al (4/50/5) catalyst (Cat) and Cu-Zn-Al-Li (40/50/5/5) catalyst (Cat-Li) were prepared. And used to synthesize methanol from CO / H 2 and CO 2 / H 2, respectively. Techniques and methods such as TPD, TPR, TPSR, pulse, CD3I-capture, isotope labeling, EPR and in-situ DRIFT were used to characterize both catalysts and to investigate the reaction mechanism. A comparative study was conducted to clarify the role of surface oxygen and surface hydrogen on CO 2 and CO activation. A CO / CO 2 hydrogenation mechanism evidenced by formate and formaldehyde hydrogenation and methanol oxidation results is presented. Methanol synthesis activity was improved by adding Li + to Cat due to the hydrogen vacancy formed by the Cu2 + substitution of Li + on the CuO lattice. CO 2 can be activated by a trapped electron (F-center) and the resulting CO 2 - can easily be hydrogenated to formic acid and methylene bis-oxalyl, which decomposes to form H 2 CO and surface oxygen. CO can be activated by surface oxygen, the generated CO2- will follow the route of CO2 hydrogenation. In the CD3I-captured experiment, we captured surface oxygen. In the absence of surface oxygen, CO may be directly hydrogenated to formic acid groups, a pathway in the hydrogenation of CO 2. The H2CO surface model produced by methylene bis-oxalyl may be different from the H2CO surface model generated by formaldehyde adsorption or CO hydrogenation.