利用热重分析的方法研究了Fe2O3在竖式电阻炉内被CO/CO2混合气体还原,Na2O对其还原行为的影响,共设计了4个成分,分别为纯Fe2O3、Fe2O3-1%Na2O、Fe2O3-3%Na2O和Fe2O3-5%Na2O.在还原过程中由于还原失氧引起的试验小饼失重量被实时记录下来,根据这些数据可以计算出还原反应速率以及化学反应的速率常数,以此来判断Na2O对Fe2O3还原性的影响.同时利用扫描电镜观察了还原后试样的微观形貌变化.研究发现:Na2O的存在将阻碍Fe2O3的还原.通过对还原后小饼的显微形貌观察,结合FeO-Na2O二元相图,发现这种负面影响主要是由于在还原过程中产生液相引起的.另外,还检测了还原前后试验小饼的孔隙率和体积变化.检测结果确认:还原后含Na2O的试验小饼的孔隙率和体积都有所下降.分析认为这种现象同样归因于还原过程中液相的产生.
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