| 摘要 |
PURPOSE:To obtain the titled iron oxide powder consisting of single magnetite phase, easily and stably, without leaving hematite phase nor producing metallic iron, by reducing an alpha-Fe2O2 specimen with a reducing gas passed through an iron oxide powder layer. CONSTITUTION:A reaction tube 2 made of quartz or ceramic material, etc. and placed in a tubular electrical furnace 1 is charged with a heat-resistant vessel 5 such as ceramic boat, quartz boat, etc. containing alpha-Fe2O3 (hematite) 4 and an iron oxide powder layer 6 composed of hematite, magnetite or their mixture which keeps its shape with a heat-resistant gas-permeable materials 7, 7 such as porous ceramics, quartz wool, etc. The reaction tube 2 is heated at about 350 deg.C, and H2 gas (O2: <35ppm proof) is sent from the H2 gas bomb 3 to the reaction tube 2 for about 1hr to effect the reduction and heat-treatment of the hematite specimen 5 and obtain the titled iron oxide powder consisting of single hematite phase. |
