【摘要】 提出了以MnO2-Fe2O3为原料经一步熔盐电解得到FeMn4粉末工艺,具有工艺流程短、低能耗、无环境污染等特点。采用850℃的NaCl-CaCl2混合熔盐体系,以烧结后的MnO2-Fe2O3片作为阴极,高密度石墨碳棒作阳极,在一定槽电压下进行电解。记录电解过程中电流变化,利用X射线衍射仪分析电解产物的成分,扫描电子显微镜观察电解产物形貌,激光粒度分析仪测定粉末的粒度。研究了不同的烧结温度、电解电压、电解时间、粒度对电脱氧反应的影响。结果表明,采用熔盐电解固体MnO2-Fe2O3直接制备出高纯度的立方体晶格FeMn4粉末(平均粒径D50为16.95μm),其适宜工艺条件为:球磨3 h(平均粒径D50为6.454μm),成形压力20 MPa,烧结温度800℃,烧结时间5 h,3.20 V的槽电压、850℃的CaCl2-NaCl熔盐中电解18 h。更多还原

【Abstract】 FeMn4 was prepared by electro-deoxidation from MnO2-Fe2O3 in NaCl-CaCl2 melt at 850℃,as a method of short flow,low energy cost and no environmental impact.MnO2-Fe2O3 powder was compacted into pellets and sintered to form an assembled cathode,electrolyzed under constant cell voltage,with a high density graphite anode.The current change during electrolysis process was recorded.XRD was used to determine the composition of the product.SEM was used to analysis the morphology of the product.The particle size of powder was determined by means of laser particle size analyzer.The influence of sintering temperature,electrolysis voltage and electrolysis time,particle size on electro-deoxidation reaction was investigated.The results show that high purity FeMn4 powder with average grain size of 16.95μm was obtained by direct electrochemical reduction of solid MnO2-Fe2O3,and the proper conditions are:ball-milling for 3 h(for obtaining average grain size of 6.454 μm),pressing under 20 MPa,sintering at 800℃ for 5 h,electrolysis under 3.20 V cell voltage in 850℃ CaCl2-NaCl melt for 18 h.更多还原