MCM-41负载氧氮化钼的制备和表征

PREPARATION AND CHARACTERIZATION OF MCM-41 SILICATE SUPPORTED MOLYBDENUM OXYNITRIDES

将MoO3和介孔材料MCM 41的机械混合物热处理得到MoO3/MCM 41复合体 ,将MoO3/MCM 41在氨气氛中于 70 0℃氮化处理 3h ,制备了氧氮化钼负载的MCM 41催化材料。用XRD ,XPS和氮吸附脱附等手段表征了该材料。结果表明 :在XRD图谱中出现氧氮化钼的微弱衍射峰 ,证明通过这种方法得到的材料中的氧氮化钼呈现结晶趋势。XPS谱表明 :Mo存在多种化学状态。氧氮化钼负载的MCM41的比表面积 ,孔体积和孔径等参数小于MoO3/MCM 41和纯MCM

The MCM-41 supported molybdenum oxynitrides catalyst was prepared by nitriding MoO3/MCM-41 under NH3 atmosphere at 700°C for 3 h, in which MoO3/MCM-41 was prepared via thermal spreading the mechanical mixture of MoO3 and MCM-41. XRD, XPS and N2 adsorption desorption isotherms were used to characterize the material obtained. The results show that the molybdenum oxynitrides species in the materials appear to be crystallized, which is proved from the corresponding XRD peaks. The XPS results reveal that there are three chemical states for molybdenum in the catalyst, i.e., Mo(VI), Mo(V) and Mo(IV). The BET surface area pore volume and pore diameter of the catalyst are smaller than those of MoO3/MCM-41 and pure MCM-41 after the nitriding process.