铁锆氧化物催化剂上苯酚和甲醇气相邻位烷基化反应

采用共沉淀法制备了不同锆含量的铁锆氧化物催化剂, 考察了它们在苯酚和甲醇气相邻位烷基化反应中的催化性能. 结果表明, 铁锆两组分氧化物催化剂具有良好的催化活性和邻位选择性, Zr、Fe摩尔比为0.5/100的催化剂上苯酚的转化率达到99.2%, 主要产物邻甲酚和2,6-二甲酚的选择性分别为22.6%和77.0%, 随着反应温度的提高, 2,6-二甲酚的选择性增加. 铁锆氧化物表面存在的相对较强的酸碱中心可能是获得较高苯酚转化率和2,6-二甲酚选择性的主要原因.

Vapour Phase ortho-Selective Alkylation of Phenol with Methanol over Fe-Zr Oxide Catalysts

Fe-Zr oxides with different Zr/Fe molar ratios were prepared by a co-precipitation method and used as catalysts for the vapor phase ortho-selective alkylation of phenol with methanol. Results showed that the Fe-Zr oxide catalysts had relatively high activity and ortho-selectivity. Among them, the sample with nZr/nFe=0.5/100 exhibited the highest activity (99.2% phenol conversion) with a selectivity of 22.6% to o-cresol and 77.0% to 2,6-xylenol. An increase in reaction temperature could further improve selectivity for 2,6-xylenol. The presence of relatively strong acid-base sites may be responsible for the high phenol conversion and the high 2,6-xylenol selectivity.