Probing Surface Properties and Reaction Intermediates During Heterogeneous Catalytic Oxidation of Acetaldehyde
Probing Surface Properties and Reaction Intermediates During Heterogeneous Catalytic Oxidation of Acetaldehyde
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DOI：
10.1002/cctc.200900099
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发表时间：
2009-10
期刊：
影响因子：
4.5
通讯作者：
R. Kydd;W. Y. Teoh;J. Scott;D. Ferri;R. Amal
中科院分区：
文献类型：
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作者：
R. Kydd;W. Y. Teoh;J. Scott;D. Ferri;R. Amal
考察了铜在不同金属氧化物载体上对乙醛(ACA)催化氧化的影响。催化剂的ACA转化活性和CO_2产率的大小顺序为：Cu/CeO_2>；Cu/TiO_2；≈；ACA在CeO2、TiO2和ZrO2碱性载体上自发吸附转化为表面羧酸盐，如桥式和双齿乙酸酯。详细的程序升温研究发现，铜/CeO2的高活性主要源于CeO2载体固有的高活性。相比之下，对铜/二氧化钛的类似研究表明，铜对活性的改善主要是相加的。尽管CuCeO2和CuTiO2ACA氧化活性的来源不同，但碱度诱导的羧酸盐生成和表面氧的有效性的整体协同效应被认为是影响整体催化反应活性的关键因素。
The influence of Cu on various metal oxide supports was investigated for the catalytic oxidation of acetaldehyde (ACA). The activity of the catalysts towards ACA conversion and the CO2 yield decrease in the order: Cu/CeO2>Cu/TiO2≈Cu/ZrO2> Cu/Al2O3>Cu/SiO2. Spontaneous adsorptive conversion of ACA to surface carboxylates, such as bridging and bidentate acetates, was detected over the basic supports CeO2, TiO2, and ZrO2. Detailed temperature‐programmed studies found the high activity of Cu/CeO2 to stem mainly from the intrinsically high activity of the CeO2 support. In contrast, similar studies on Cu/TiO2 demonstrated the activity improvements imparted by Cu were predominantly additive. Despite the difference in origin of ACA oxidation activity over Cu/CeO2 and Cu/TiO2, the overall concerted effects of basicity‐induced carboxylate formation and availability of surface oxygen were thought to be overriding factors crucial in the overall catalytic reactivity.