摘要
电解含有铁氧化物的熔渣是一个潜在的减少甚至消除CO2排放的钢铁冶炼短流程新工艺.本文采用MgO或Y2O3稳定的氧化锆管内装碳饱和铁熔体做阳极,构建可控氧流电池:铁棒|Fe+FeO(slag)|ZrO2(MgO或Y2O3)|[O](Fe+C饱和)|石墨棒.在1723 K高温下通过测定电池开路电压-时间曲线、线性扫描伏安曲线、恒电压电解曲线研究了SiO2-CaO-Al2O3-MgO-FeO熔渣的电解还原行为,并借助扫描电镜与能谱分析了残样的显微结构与成分.结果表明:在本实验条件下,测定获得SiO2-Ca O-Al2O3-MgO-FeO熔渣中FeO的分解电压约为-0.25 V,测定结果位于Fact Sage热力学软件理论计算值范围内,表明采用本实验装置测定熔渣中FeO分解电压是可行的.在外加电压条件下可以从SiO2-CaO-Al2O3-MgO-FeO熔渣中电解还原获得金属铁(或铁合金).可控氧流电解还原电流的大小及FeO还原效果与外加电压、ZrO2稳定剂的种类和ZrO2管(阳极)插入熔渣中的深度等因素有关.
Direct electrolysis of molten oxide slag containing iron oxide by using an inert anode is a novel potential route of ironmaking to decrease or even eliminate CO2 emissions. In this paper,an electrolytic cell with a controlled oxygen flow was constructed through a one-end-closed MgOor Y2O3 stabilized ZrO2 solid electrolyte tube loaded with carbon saturated iron melt as an anode: Iron rod | Fe + FeO(slag)| ZrO2(MgOor Y2O3) |[O](Fe + saturated C)|graphite rod. Electrolytic reduction behavior of SiO2-CaO-Al2O3-MgO-FeOmolten slag was studied through using open circuit voltage-time curve,linear scanning volt-ampere curve and potentiostatic electrolytic curve at 1723 K. Microstructure and composition of the residual sample were investigated by means of scanning electron microscope and energy spectrum analysis. The results showed that: under the experimental condition, the decomposition voltage of the FeOin the SiO2-CaO-Al2O3-MgO-FeOslag is about-0. 25 V. The measured results are in range of the theoretically calculated values from the Fact Sage thermodynamic softw are,indicating that it is feasible to employ the experimental device to measure the decomposition voltage of FeOin the molten slag. By adding a voltage,a metallic iron(or an iron alloy) could be obtained from the SiO2-CaO-Al2O3-MgO-FeOslag through the electrolytic reduction. C urrent of electrolytic reduction with a controlled oxygen flow and effect of the FeOreduction were associated with some factors such as the adding voltage,type of the ZrO2 stabilizer,and the depth of ZrO2 tube(anode) inserted into the slag,etc.
出处
《材料与冶金学报》
CAS
北大核心
2015年第2期114-120,130,共8页
Journal of Materials and Metallurgy
基金
国家自然科学基金项目51174148资助