过渡金属取代型杂多阴离子柱撑水滑石上环己烯的催化氧化性能

类水滑石及杂多阴离子柱撑水滑石具有可调变的二维孔道结构,活性组分可在较宽的范围内进行调变,从而使其成为有应用前景的氧化催化剂'·'．迄今,以完整结构形态的水滑石为催化剂的催化氧化研究尚未见报道．我们发现［'－'j,含可变价元素的类水滑石和过渡金属取代型杂多阴离子柱撑水滑石具有在较低温度下活化分子氧,从而实现活泼烃类a－H氧化的能力·本文报道了M。AIXW;;ZO。。（M＝Mg'",Zn'";X＝p,St;Z＝Mn2＋,Fe2＋,C。2＋,Ni'",Cll'"）层柱材料上环己烯的催化氧化行为．1实验部分M。AI－XW;;ZO。。系列杂多…

Catalytic Oxidation of Cyclohexene over Transition Metal Substituted Polyoxometalate Pillared Layered Double Hydroxides

POM-LDHs with the composition of MAI-XW₁₁ZO₃₉(M=Zn, Mg; X=P, Si; Z=Mn²⁺, Fe²⁺, Co²⁺, Ni²⁺, Cu²⁺) were synthesized, and their catalytic properties for oxidation of cyclohexene in the presence of dioxygen were studied. The results obtained show that the oxidation of cyclohexene gives mainly α-H oxidation products, and the reaction activities greatly depend on the nature of the substituted transition metals in the POM pillars, i. e.,with different Z ions, the activity is in the order: Co²⁺～Cu²⁺～Mn²⁺》Ni²⁺～Fe²⁺. In addition, the central atom in the POM pillars has some effects on the oxidation of cyclohexene.The activity increases when P is used instead of Si. No obvious difference between the activities of ZnAl and MgAl layers were observed.