高Cu含量MCM-41在苯直接羟基化反应中的催化性能

Catalytic Performance of Cu-MCM-41 with High Copper Content for the Direct Hydroxylation of Benzene to Phenol

考察了高铜含量(最高达26·0%)且铜原子主要处于中孔骨架的Cu-MCM-41在苯/过氧化氢直接羟基化制备苯酚反应中的催化性能,研究了铜含量、催化剂用量、溶剂种类、反应物摩尔比、温度以及时间等对催化剂活性的影响.结果表明,该催化剂在苯直接羟基化反应中具有良好的催化活性,在最佳反应条件下,可使苯转化率达52·9%,苯酚选择性达58·9%,苯酚收率达31·2%,优于文献报道的低铜含量中孔分子筛的催化结果.另外,从反应机理对影响反应的因素进行了初步探讨.

Cu-MCM-41 catalysts in which the copper content could be up to 26.0% and most of the copper atoms were incorporated into the silica framework were prepared. They exhibited high catalytic activity for direct hydroxylation of benzene with H2O2. Under the optimal reaction conditions, a 52.9 % conversion of benzene and 31.2 % yield of phenol were obtained, which was higher than the catalysts reported in the literature using other mesoporous materials with low copper content. The influence of various reaction parameters such as the copper content, the molar ratio of H2O2/benzene, the amount of catalyst, solvents, and the reaction temperature on the catalytic activitv was studied and discussed in accordance with the reaction mechanism.