摘要
在298～1073K使用程序升温还原技术（TPR）结合XRD、Mossbauer谱，研究了尖晶石结构铁酸盐MFe2O4（M＝Fe，Mn，Co，Ni）的还原性能，考察了铁酸盐的组成及第二金属组分（Mn、Co、Ni）对铁酸盐还原性能的影响。第二金属组分的加入稳定了亚铁物相，按Fe、Co、Mn、Ni顺序，MO与FeO的相互作用能力、MO—FeO固溶体的稳定性及铁酸盐MFe2O4还原为MO－FeO的能力增强，MO－FeO进一步还原为α－Fe的能力减弱。
The reduction property of ferrite MFe2O4 (M=Fe, Mn, Co, Ni) with spinel structurewas studied by temperature programmed reduction reduction technology in temperature range of298~1073K combining with XRD and Mossbauer spectra. Effects of ferrite composition andthe second metal component M (Mn, Co, Ni) on ferrite reduction property were also discussed.In the TPR profiles, the sample ofγ-Fe2O3 appeared two peaks at 673 and 863 K assigned toFe3O4 andα-Fe respectively. The ferrites MFe2O4 (M=Mn, Co, Ni) with the spinel-type structure all appeared two TPR peaks which were ascribed to MO-FeO andα-Fe, andα-Fe,resprctively. The peak temperature of reducing to MO-FeO decreased in order of Fe, Co, Mn,Ni, While the order of the peak temperature of further reducing toα-Fe is on the opposite.The introduction of the second metal component stabilized ferrous phase, the interaction betweenMO and FeO, the stability of MO-FeO solid solution and the ability of ferrite MFe2O4reducing into MO-FeO increased in the order of Fe, Co, Mn, Ni, while the ability ofMO-FeO reduced intoα-Fe decreased in this order.
基金
国家自然科学基金!29703002
