【摘要】 用X射线光电子能谱(XPS)测试技术,对CO偶联制草酸二乙酯中α-Al2O3为载体钯催化剂进行表征,探讨催化反应机理。研究表明CO偶联制草酸二乙酯中反应物与催化剂之间存在着相互作用,Pd的吸附作用促进了反应物亚硝酸乙酯的分解,证实了亚硝酸乙酯分解产物将活性组分Pd0氧化为Pd2+。XPS实验测定结果显示,CO偶联反应步骤中涉及到两种有关的中间络合物双烷氧基钯络合物Pd2+(-OC2H5)2和双烷氧羰基钯络合物Pd2+(CO-OC2H5)2,后者是一个极不稳定的络合物。根据催化机理中反应物和催化剂之间电子传递方式,该催化体系应归为氧化-还原型催化反应。更多还原

【Abstract】 α-Al₂O₃ supported palladium catalysts for carbon monoxide coupling to diethyl oxalate were characterized by X-ray photoelectron spectroscopy（XPS） and the reaction mechanism was discussed.The results showed that an interaction between reactants and the catalyst existed in carbon monoxide coupling to diethyl oxalate.The adsorption over Pd was found to accelerating the decomposition of reactant ethyl nitrite and the decomposition product of ethyl nitrite was confirmed to oxidize the active component Pd⁰ to Pd²⁺.The XPS experimental results indicated that there were two intermediate complexs,bis（ethoxy） palladium and bis（ethoxycarbonyl） palladium,referred to the process of carbon monoxide coupling reaction,and the later was extremely unstable.According to the electron transfer mode between the reactants and catalysts in the catalytic mechanism,this catalytic system belongs to the kind of red-ox reaction.更多还原