摘要
探讨钛铁矿氧化过程中的物相转化、形貌改变及其氧化机理。在700～800℃时,钛铁矿(FeTiO3)转变为赤铁矿(Fe2O3)和金红石(TiO2),当温度高于900℃时,三价铁板钛矿开始形成。原始的钛铁矿粉末呈现顺磁性,但是经过中温(800～850℃)氧化后,氧化产物呈现弱铁磁性。同时,讨论钛铁矿的氧化机理。通过对微结构的观察,发现在中温氧化过程中颗粒表面出现大量微孔,其在氧化过程中能够强化氧的传质。
Phase transitions, morphology changes, and oxidation mechanism of the ilmenite oxidation process were investigated. FeTi03 transforms to hematite and rutile when oxidation at 700-800 ℃, and pseudobrookite is formed when the oxidation temperature reaches 900 ℃. The initial ilmenite powder exhibits paramagnetism; however, after being oxidized at the intermediate temperature （800-850 ℃）, the oxidation product exhibits weak ferromagnetism. The oxidation mechanism was discussed. The microstructure observations show that a lot of micro-pores emerge on the surfaces of ilmenite particles at the intermediate temperature, which is deemed to be caoable ofenhancin~ the mass transfer ofoxgen during oxidation.
基金
Project(51074105) supported by the National Natural Science Foundation of China
Project(51225401) supported by the China National Funds for Distinguished Young Scientists
关键词
钛铁矿
物相转变
微观形貌
氧化机理
ilmenite
phase transitions
micro-morphology
oxidation mechanism
