Five hundred ppm Pd/CeO₂ catalyst was prepared and evaluated in selective hydrogenation of acetylene in large excess of ethylene since ceria has been recently found to be a reasonable stand-alone catalyst for this reaction. Pd/CeO₂ catalyst could be activated in situ by the feed gas during reactions and the catalyst without reduction showed much better ethylene selectivity than the reduced one in the high temperature range due to the formation of oxygen vacancies by reduction. Excellent ethylene selectivity of ∼100% was obtained in the whole reaction temperature range of 50°C–200°C for samples calcined at temperatures of 600°C and 800°C. This could be ascribed to the formation of Pd_xCe_1−xO_2−y or Pd-O-Ce surface species based on the X-ray diffraction and X-ray photoelectron spectroscopy results, indicating the strong interaction between palladium and ceria.

制备了500 ppm Pd / CeO ₂催化剂，并在大量过量的乙烯中乙炔的选择性加氢中进行了评估，因为最近发现二氧化铈是该反应的合理独立催化剂。Pd / CeO ₂催化剂可在反应过程中通过进料气原位活化，并且在高温范围内未还原的催化剂比在还原后的乙烯具有更好的乙烯选择性，这是由于通过还原形成的氧空位。在50°C–200°C的整个反应温度范围内，对于在600°C和800°C的温度下煅烧的样品，乙烯的选择性达到约100％。这可能归因于Pd _x Ce _{1- x} O的形成基于X射线衍射和X射线光电子能谱结果的_{2- y}或Pd-O-Ce表面物质，表明钯和二氧化铈之间有很强的相互作用。