Fe对(Cu-Ni-Fe)-xNiFe_2O_4复合惰性阳极低温铝电解成膜机制的影响

Influence of Fe on film-forming mechanism of (Cu-Ni-Fe)-xNiFe_2O_4 composite inert anode for aluminum electrolysis in low temperature electrolyte

以高温固相合成的NiFe_2O_4和Cu,Ni,Fe金属粉为原料,采用冷压烧结法制备不同合金相含量的(Cu-Ni-Fe)-xNiFe_2O_4(x=50,60,70,80,质量分数/%,下同)金属基复合惰性阳极材料,研究合金相中Fe元素对(Cu-Ni-Fe)-xNiFe_2O_4金属基复合惰性阳极材料烧结和电解过程中基体成分与微观组织的影响,发现合金相中的Ni,Fe及NiFe_2O_4陶瓷相在烧结和电解过程中发生了可逆的氧化还原反应,使得NiFe_2O_4相发生解离和再生成。对(Cu-Ni-Fe)-xNiFe_2O_4金属基复合惰性阳极材料进行了低温电解性能测试,研究其在电解过程中的成膜过程和腐蚀行为。结果表明:(Cu-Ni-Fe)-xNiFe_2O_4金属基复合惰性阳极材料电解过程中电压稳定,铝液杂质含量低于0.7%(质量分数),有望解决金属陶瓷阳极热稳定性差的问题,是理想的惰性阳极材料。

Several(Cu-Ni-Fe)-:rNiFe2O4(r=50,60,70,80,mass fraction/%)composite inert anodes with different contents of alloy phase were prepared using Cu,Ni,Fe and high-temperature synthetic NiFe2 O4 by cold-pressing sintering method.The effect of Fe on the composition and microstructure of the(Cu-Ni-Fe)-xNiFe2O4 composite inert anodes during sintering and electrolysis process was studied.It is found that the redox reaction between Ni/Fe and NiFe2O4 phase occurs,leading to the disso ciation and regeneration of NiFe2O4.In addition,the tilm-forming process and corrosion behavior of the(Cu-Ni-Fe)-xNiFe2O4 anodes were studied through low-temperature aluminium electrolysis test.The results indicate that the cell voltage is stable during electrolysis and the impurities in the produced aluminium are less than 0.7%(mass fraction),which indicates that(Cu-Ni-Fe)-xNiFe2O4 composite inert anode is one of the most promising inert anode materials,and the poor thermal stability of the ceramic anode s expected to be solved.