| 金属氧化物-Laponite黏土复合材料负载氧化钴催化剂的制备及对苯的催化消除性能 |
| 摘要点击 1802 全文点击 1070 投稿时间：2014-02-25 修订日期：2014-05-09 |
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| 中文关键词 金属氧化物-Laponite黏土复合材料 硅酸镁锂 苯 氧化钴 催化氧化 |
| 英文关键词 metallic oxide-clay composites laponite benzene Co3O4 catalytic oxidation |
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| 中文摘要 |
| 以多核羟基阳离子或简单金属阳离子为前驱体，合成了Al、Ce和Zr等金属氧化物-Laponite黏土复合材料，以之为载体负载制备Co3O4催化剂. 结果表明，与原黏土Laponite相比，复合处理后材料的孔隙变得发达，孔体积增加，Al和Ce的氧化物复合的Laponite黏土材料的孔体积超过0.75 cm3 ·g-1；负载Co3O4催化剂后没有改变等温线的类型，但随着负载量的增加，材料对氮气的吸附量逐渐减少，表明Co3O4填充了部分孔道，导致孔体积的减小. 复合的金属元素类型对负载型的Co催化剂的分散度和催化活性都有影响. 结果表明，根据（311）衍射的半峰宽，使用Scherrer方程计算得到Co负载量为21.3%的Fe、Zr、Ce、Al氧化物复合Laponite黏土材料催化剂上，Co3O4颗粒的平均粒径分别为17.2、16.0、16.5和18.0 nm；对于氧化铝复合的Laponite黏土材料而言，21.3%的Co负载量比较合适，苯的完全转化温度约为350℃；不同金属氧化物与Laponite黏土复合的载体催化剂中，氧化锆的活性最好，能在310℃实现苯的完全转化. |
| 英文摘要 |
| Laponite clays composited with alumina, ceria and zirconia etc. were prepared using polyoxocations or simple metal ions as precursors, and then cobalt oxide was loaded onto them to obtain the catalysts. The results showed that compared with laponite clays, the as-prepared laponite had wide range of pore size distribution and increased pore volume. The pore volumes of laponite clays composited with alumina and ceria were more than 0.75 cm3 ·g-1. N2 isotherm type was maintained after Co3O4 loading, however, the N2 adsorption decreased with the increase of Co3O4 loading, indicating the decrease of pore volume, which was caused by the blockage of metallic oxide/clay composites support. Furthermore, dispersion and catalytic performance of the catalysts were significantly influenced by the composited metallic elements. It was shown that according to the diffraction peak half-width of 311 crystal facet and scherrer equation, when the Co loading was 21.3% at laponite clays composited with Fe, Zr, Ce, Al, the average sizes of Co3O4 were 17.2, 16.0, 16.5 and 18.0 nm, respectively. Alumina composited clay with 21.3% Co loading showed high catalytic activity, the complete conversion temperature of benzene was 350℃. Among metallic oxide/laponite composites, the ZrO composited laponite with 21.3% Co loading exhibited the best catalytic performance, which could completely convert benzene at 310℃. |
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