制备均分散铁红微粉的新方法

A New Method of Preparing Uniform Hematite Superfine Powder

以ＦｅＳＯ４为原料，采用两步法液相氧化工艺制备了均匀αＦｅ２Ｏ３微粉，研究了反应悬浮液中Ｆｅ（Ⅱ）浓度及初始ｐＨ值对ＦｅＯＯＨ相转化的影响。结果表明，Ｆｅ（Ⅱ）浓度及ｐＨ值对ＦｅＯＯＨ→αＦｅ２Ｏ３相转化时间有很大影响，在ｐＨ值近中性时，少量的Ｆｅ（Ⅱ）离子对相转化具有显著的催化作用，因而缩短了反应周期。通过改变生长与成核两阶段消耗ＦｅＳＯ４的比值，可方便地人为控制αＦｅ２Ｏ３的粒度。

The uniform hematite superfine powder of different size was prepared by two step method from Fe(OH) 2 suspensions. Effects of Fe(Ⅱ) concentration in suspensions and pH values on  FeOOH phase transformation were studied. The results showed that the Fe(Ⅱ) concentration and pH greatly influence on the transformation of  FeOOH to α Fe 2O 3. At pH near neutral solution,a small portion of Fe(Ⅱ) can apparently catalyze the phase transformation and consequently shorten the reaction time. The particle size of α Fe 2O 3 can be conveniently controlled by changing the ratio of Fe(Ⅱ) quantity in crystal growth period and that in nucleation period.