论文部分内容阅读
FFC(熔盐电脱氧)工艺是一种用电化学还原法从混合金属氧化物制备Ti-Fe合金的新工艺,具有短流程、低能耗的特点。选择合适的阴极制备工艺对后续的电化学还原至关重要。采用模压成型和烧结的工艺制备TiO2-Fe2O3混合氧化物阴极,研究了阴极片的成型压力、造孔剂种类及用量、烧结温度等阴极成形和烧结过程中的主要因素对阴极孔隙率和微观结构的影响。用SEM及EDS对阴极片的微观结构和元素分布进行分析。结果表明,用碳酸氢氨作造孔剂时,阴极片的孔隙率受温度的影响较大;随着温度的升高和造孔剂含量的增多,烧结的阴极片颗粒直径不断增大,并且在孔隙周边的颗粒直径相对于其他部位要更大些;随着温度的等幅度增加,颗粒直径在造孔剂含量高时随温度升高而增长的幅度较大。对烧结片局部氧元素含量分布不均的现象进行了分析,其原因是高温下物质的内能较高,当能量达到反应活化能时会发生氧化物的分解反应,分解出的氧气通过孔隙向周围扩散,使得局部的氧含量较高。
FFC (Molten Salt Electrodeoxidation) process is a new electrochemical reduction process for preparing Ti-Fe alloy from mixed metal oxides with short process and low energy consumption. Choosing a suitable cathode preparation process is crucial for subsequent electrochemical reduction. The cathode of TiO2-Fe2O3 mixed oxide was prepared by compression molding and sintering. The effects of forming pressure and pore-forming agent, sintering temperature and other factors on cathode porosity and microstructure Impact. The microstructure and elemental distribution of the cathode sheet were analyzed by SEM and EDS. The results show that the porosity of the cathode sheet is greatly affected by the temperature when ammonia bicarbonate is used as pore forming agent. With the increase of temperature and the content of pore former, the diameter of the sintered cathode sheet increases. The diameter of the particles around the pores is larger than that of other parts. With the increase of the temperature, the diameter of the particles grows with the increase of the temperature when the content of the pore former is high. The reason for the uneven distribution of the oxygen content in the sintered sheet was analyzed. The reason is that the internal energy of the material at high temperature is high. When the energy reaches the reaction activation energy, the decomposition reaction of the oxide occurs. The decomposed oxygen passes through the pores Diffusion around, making the local high oxygen content.