以TiO2为载体,采用浸渍法制备了不同配比的MnCe复合型催化剂,并采用X射线衍射(XRD)、氧气的程序升温脱附(O2-TPD)和氢气的程序升温还原(H2-TPR)对制备的催化剂进行表征,比较了催化剂催化氧化(燃烧)甲苯的活性。研究结果表明,所制备的催化剂MnCe(y)Ox/TiO2对甲苯有明显的催化活性。当Ce/(Mn+Ce)的摩尔比为0.1时,催化剂MnCe(0.1)Ox/TiO2的催化活性最高,甲苯的转化率达到90%时的温度为254℃。在催化剂MnOx/TiO2中掺杂少量的Ce元素,有利于活性组分Mn物种在载体表面上以更小颗粒而且更高的分散度存在,从而提高催化剂的催化活性。
A series of MnCe(y)O_x/TiO_2 catalysts with different Ce/(Mn+Ce) molar ratio were prepared by im- pregnation method. Then, the prepared samples were characterized by X-ray diffraction (XRD), oxygen tem- perature programmed desorption (O2-TPD) and hydrogen temperature programmed reduction (H2-TPR). Cata- lytic activity tests of the prepared samples were performed in a fixed-bed reactor. The results show that the cat- alysts MnCe(y)O_x/TiO_2 had good catalytic activity for oxidation of toluene. The MnCe(0.1)Ox/TiO2 catalyst was the most active catalyst among the catalysts tested, and the reaction temperature required for 90% conver- sion of toluene was 254℃. The addition of a small amount of cerium favored the formation of smaller particles and higher dispersion of manganese species on the support. As a consequence of that, the catalytic activity of the catalyst MnCe(0.1)Ox/TiO2 was greatly improved in comnarison with the catalyst MnOx/TiO2.