【摘要】 研究了焙烧温度对无定形氧化锰的织构及其催化苯甲醇液相氧化反应性能的影响.结果表明,在焙烧温度不高于400℃的条件下,MnOx均保持无定形结构,进一步提高焙烧温度会促使无定形MnOx转变为晶相的OMS-2和Mn2O3.不同氧化锰催化剂的质量比活性随焙烧温度的升高而逐渐降低,无定形MnOx比晶相氧化锰(OMS-2,γ-MnO2和Mn2O3)具有更高的质量比活性,而110℃干燥的无定形氧化锰具有最高的活性.H2-程序升温还原研究表明,氧化锰的起始还原温度与其质量比活性之间存在线性逆变关系,表明氧化锰的还原性能是决定其催化活性的关键因素.更多还原

【Abstract】 The effect of calcination temperature on the textual structure and catalytic properties of amorphous MnOx for the liquid-phase aerobic oxidation of benzyl alcohol was studied. The amorphous nature of the synthesized MnOx was retained when the calcination temperature was lower than 400 ℃, and calcination temperatures higher than 500 ℃ led to the transformation of amorphous MnOx to crystalline OMS-2 and Mn2O3. Catalytic reaction studies revealed that the amorphous MnOx exhibited higher mass specific activity than OMS-2, Mn2O3, and γ-MnO2, and MnOx calcined at 110 ℃ showed the highest activity. An inverse linear correlation between the onset reduction temperature in H2-TPR and the mass specific activity of the various manganese oxides was observed. This suggested that the reducibility of manganese oxide is the key factor responsible for its activity for the aerobic oxidation of benzyl alcohol.更多还原