【摘要】 在温和条件下对铁基复合氧化物催化苯酚和过氧化氢的羟基化反应进行了研究.结果表明,活性组分、载体以及催化剂/苯酚(质量比)、过氧化氢/苯酚(摩尔比)、反应温度和反应时间等对苯酚羟基化反应具有重要影响.Fe-A催化剂的活性组分形成了α-Fe2O3和尖晶石结构;Fe-B催化剂活性组分以非晶态分布在催化剂上,高度弥散,具有更好的催化性能.溶剂的加入,有助于苯酚和过氧化氢的混合,水是理想的羟基化反应溶剂,可以实现苯酚和过氧化氢水溶液的互溶,有利于·OH的生成.以Fe-B作催化剂,水为溶剂,反应温度65℃,反应时间1h,催化剂/苯酚(质量比)=0.02,水/苯酚(体积比)=2.0,过氧化氢/苯酚(摩尔比)=0.3,苯酚转化率21.6%,苯二酚选择性86.5%.更多还原

【Abstract】 Catalytic performance for the hydroxylation of phenol with hydrogen peroxide using Iron\|based composite metal oxides supported on γ\|Al2O3 as catalysts has been investigated. It was found that these two catalysts, Fe\|A and Fe\|B had noticeable catalytic activities for the reaction and Fe\|B exhibited higher catalytic performance than that of Fe\|A thanks to the appropriate dispersion of active components on γ\|Al2O3 carrier. The cheaper catalyst Fe\|B achieved that a phenol conversion and a diphenol selectivity were 21.6% and 86.5%, respectively. Water is a suitable reaction medium for the hydroxylation of phenol with hydrogen peroxide. Too long reaction time is unsuitable because diphenols could be further oxidized.更多还原