利用原位红外技术在常压下分别对CO气相催化偶联与亚硝酸乙酯反应合成草酸二乙酯在钯系催化剂上的吸附与反应机制进行了研究 ,发现CO主要吸附在活性中心钯上 ,并存在线式与桥式两种吸附形式 .研究表明二者之间存在过渡态 ,线式吸附的CO更容易参与CO偶联反应 ,而桥式吸附的CO对反应也具有一定的贡献 .亚硝酸乙酯在反应温度下性质很活泼 ,红外光谱证明在催化剂表面上有吸附的EtO·存在 .原位红外反应的研究结果进一步证实了烷氧羰基钯中间配合物的存在 ,并由此进一步探讨了该反应的机理 In-situ infrared (IR) technique was used to study the adsorption and reaction mechanism of diethyl oxalate on palladium-based catalysts by CO catalyzed coupling reaction of CO with ethyl nitrite at atmospheric pressure respectively. It was found that CO was mainly adsorbed on active palladium , And there exist two kinds of adsorption forms of wire type and bridge type.The research shows that there exists transitional state between the two, and CO adsorbed by the CO line is more likely to participate in the CO coupling reaction, while CO adsorbed on the bridge also contributes to the reaction. Ethyl nitrate was very active at the reaction temperature, and IR spectroscopy proved the presence of EtO · adsorbed on the surface of the catalyst. The results of the in-situ IR reaction further confirmed the existence of the intermediate complexes of alkoxycarbonylpalladium and further explored The reaction mechanism