论文部分内容阅读
用XRD、Raman、TPR和Py-IR表征乙酰丙酮络钒法制备的不同氧化物和磷酸盐负载的钒氧化物催化剂,结果表明,钒氧化物在载体MgO、Al2O3、Mg3(PO4)2、AlPO4和Zr3(PO4)4上是高分散的,没有生成明显的V2O5晶相;催化剂的可还原性与相应载体氧化物或磷酸盐的金属还原电位序有较好的对应关系,同时与其丙烷氧化脱氢活性也存在较好的平行关系,表明钒氧化物与载体的阳离子形成V-O-M桥键,该桥键氧较易移去,可能是丙烷氧化脱氢的活性氧物种;催化剂表面酸性位有利于丙烷C-H键的活化,但导致深度氧化产物增多。
The vanadium oxide catalysts with different oxides and phosphates prepared by the acetylacetonato-vanadyl method were characterized by XRD, Raman, TPR and Py-IR. The results showed that the vanadium oxide supported vanadium oxide in the carrier MgO, Al2O3, Mg3 (PO4) 2, And Zr3 (PO4) 4 are highly dispersed, and no obvious V2O5 crystal phase is formed. The reducibility of the catalyst has a good correspondence with the metal reduction potential order of the corresponding carrier oxides or phosphates. Meanwhile, There is also a good parallel relationship between hydrogen activity, indicating that the vanadium oxide and the carrier cation form V-O-M bridge, the bridge oxygen easier to remove, may be oxidative dehydrogenation of propane oxygen species; catalyst surface acidity Bits favor the activation of propane C-H bonds, but lead to an increase in deep oxidation products.