锰八面体分子筛的合成、表征及其对二甲醚燃烧的催化性能(英文)

Synthesis and Characterization of Manganese Oxide Octahedral Molecular Sieve and Its Catalytic Performance for DME Combustion

以高锰酸钾和马来酸为原料,以聚乙二醇单甲醚(MPEG)为模板剂,采用溶胶凝胶法合成了锰八面体分子筛(OMS-2),并将其用于二甲醚的催化燃烧反应.XRD,FT-IR和UV-Vis结果表明,合成的材料为隐钾锰矿型的锰氧化物.TEM结果表明合成的材料具有棒状的外形结构,其中MPEG起模板导向剂的作用.O2-TPD和H2-TPR结果表明合成的OMS-2材料容易还原,富有晶格氧.OMS-2材料在二甲醚催化燃烧中表现出优异的催化性能,能够在较低的温度下将二甲醚完全转化为CO2和H2O,晶格氧在该反应中起非常重要的作用.

Manganese oxide octahedral molecular sieve （OMS-2） was prepared by the sol-gel method using KMnO4 and maleic acid in the presence of methoxypolyethylene glycols （MPEG） and used for the catalytic combustion of dimethyl ether （DME）. XRD, FT-IR and UV-Vis data confirmed that the formation of cryptomelane-type manganese oxide. TEM results showed that the OMS-2 had rodlike shape and the MPEG played a role as a structure-directing agent in the OMS-2 formation. O2-TPD and H2-TPR results indicated that the OMS-2 was rich in facile lattice oxygen, can activate oxygen and be easily reduced by He. The OMS-2 possessed excellent catalytic performance for DME combustion, and could convert DME to CO2 and H2O at a relatively low temperature. The lattice oxygen played a key role in the DME combustion.