| 内容提要: |
CoAl mixed oxidation with various Co/Al molar ratios and calcination temperatures has been major studied in order to explore the structural changes and catalytic performance for acetone oxidation. The results indicated that catalytic activity of acetone firstly increased and then decreased with the increase of the Co/Al molar ratios and decrease with the increase of the calcination temperature. Combining with catalytic activities, TG/DTA, XRD, TPR and XPS characterization results, it can be found that catalytic activity of the catalysts with various Co/Al molar ratios is in accordance with good crystallization structure of catalyst precursor, surface Co3+/Co2+ molar ratio, low temperature reducibility and Oads/Olatt molar ratio of the catalysts; while that of the catalysts with various calcination temperatures is in accordance with layered structure of catalyst precursor, the low temperature reducibility, surface Co3+/Co2+ molar ratio. The catalytic performance of the 5:1 CoAlO-300 catalyst (T90% = 225 °C) approximated to that of the 5:1 CoAlO-200 catalyst (T90% = 222 °C), and they exhibited much better catalytic performance than the other catalysts. |