摘要
研究了空气氧化Ｍ２＋（Ｍ＝Ｍｎ、Ｆｅ、Ｃｏ、Ｎｉ）和Ｆｅ２＋的碱性悬浮液制备铁酸盐ＭＦｅ２Ｏ４的条件，考察了原料配比、ｐＨ值、氧化温度、氧化时间对生成ＭＦｅ２Ｏ４的影响。利用ＸＲＤ及ＳＥＭ检测氧化过程中沉淀物的形态和结构表明，在３４３～３５８Ｋ和Ｒ＝２ＯＨ－／（Ｍ２＋＋Ｆｅ２＋）＝１．０、Ｍ２＋／Ｆｅ２＋＝０．５（摩尔比）下用３００ｍＬ／ｈ的空气氧化Ｍｘ／３Ｆｅ１－ｘ／３（ＯＨ）２悬浮液１０～２５ｈ是ＭＦｅ２Ｏ４生成的最佳条件，此时能得到纯相的尖晶石结构铁酸盐。
The conditions for the preparation of ferrites MFe 2O 4(M=Mn,Fe,Co,Ni) were studied by the air oxidation of the suspension which is obtained by mixing M 2+ ,Fe 2+ and NaOH solutions.The influence of ratio of reagents,pH values,oxidation temperature and time on the formation of ferrites were examined.The shape and structure of precipitates during the course of oxidation were investigated by XRD and SEM.The results show that the optimum conditions are described as fllow:M x/3 Fe 1-x/3 (OH) 2 suspension is oxidized by the air (300mL/h) for 10～25h at 343～358K,R=2OH -/(M 2+ +Fe 2+ )=1.0 and M 2+ /Fe 2+ =0.5(molerate),under these conditions pure ferrites of spinel structure can be obtained.
关键词
水热氧化晶化法
生成条件
铁酸盐
Ferrites Hydrothermal oxidative crystallization Suspension Formation condition
