【摘要】 在高温 (92 3K)下分解 Fe C2 O4制备了阳离子缺位的磁铁矿 (Fe3 O4+δ,0≤δ<1 ) ,并用 H2 还原使它变为氧缺位的磁铁矿 (Fe3 O4-δ,0 <δ<1 )。在 62 3K下研究了氧缺位磁铁矿对 CO2 分解成 C的反应性能 ,发现 CO2 几乎 1 0 0 %地转化成 C,CO2 中的氧以 O2 -形式被磁铁矿的氧缺位捕获 ,变成化学计量的 Fe3 O4。 XRD、M ssbauer谱及热失重和化学分析表明 ,H2 还原磁铁矿的时间愈长 ,缺氧程度愈大 ,分解 CO2 的活性愈高 ,Fe3 O4-δ、FeδO(0 <δ<1 )和 α- Fe是 CO2 分解的活性相。更多还原

【Abstract】 A cation- deficient magnetite (Fe3 O4-δ,0 <δ<1) was prepared at high temperature 92 3 K by decomposing Fe C2 O4and then transformed into an oxygen- deficient magnetite (Fe3 O4-δ,0 <δ<1) through H2 reduction.The activity of decomposing carbon dioxide into carbon with oxygen- deficient magnetite was studied at temperature 6 2 3K. It is found that carbon dioxide can be nearly completely(10 0 % ) transformed into carbon and the oxygen in carbon dioxide is captured in the form of O2 -by the magnetite.As a resultof reaction,the oxygen- deficient magnetite is converted to the stoichiometric Fe3 O4. The results of XRD, M ssbauer spectra,thermal and chemical analysesshow thatthe longer the time thatcation- deficientmagnetite is reduced by H2 is,the higher the oxygen- deficiency degree of magnetite and the activity of itsdecomposing carbon dioxide are.α- Fe,FeδO and Fe3 O4-δ(0 <δ<1) are all the active phases of decomposing carbon dioxide.更多还原