采用红外(IR)、拉曼(Raman)、X-射线衍射(XRD)、程序升温还原(TPR)等方法考察了经硫酸根改性后的金红石(SR)与锐钛矿(SA)的混合比例变化时的负载型催化剂,MoO3/TiO2(SR+SA),的一些物理化学性质(如活性组分MoO3的分散行为、表面酸碱性、氧化还原性)的变化规律。结果表明:对于MoO3/TiO2(SR+SA)样品,低含量MoO3表面分散时倾向于优先与混合载体中的改性金红石(SR)发生作用;TiO2载体表面SO4^2-的存在,使得载体表面产生了新的酸性位,导致样品中表面分散的钼物种主要以聚合八面体状态存在。
FTIR, Raman, XRD and TPR were employed to investigate the influence of SO4^2- on the physical chemistry properties (such as dispersion of molybdena, surface acidity, oxidation and reduction) of MoO3 supported on mixed TiO2 with different rutile (SR) and anatase (SA) ratios. The results indicated that (1) molybdena would preferentially disperse on SR surface in the mixed TiO2 (SR+SA); (2) the existence of surface SO4^2- would create the Broensted acid sites on ruffle surface and lead to the formation of polymeric octahedral molybdena species instead of the isolated molybdena species.