双室电解槽中电解质渗透行为的研究

Research on osmosis behaviors of aluminum electrolyte in double-compartment cell

利用双室电解槽研究了冰晶石-氧化铝对炭阴极的渗透。研究发现,阴极室内的液面变化不明显,而阳极室内的液面变化很大,阳极室内的电解质在电场力的作用下,穿过多孔的中间壁渗透到阴极室。随着电流密度的增大,阴阳极室的液面差增大,电渗速度与电流密度成正比。利用EDX分析发现,渗透到槽壁中的物质主要是冰晶石和氟化钠,钠和铝的含量很少,并且阴极壁中的含量要大于阳极壁,电解质是向阴极渗透的。

The research on osmosis of cryolite-alumina to the carbon cathode using double-compartment cell has discovered that almost no change of liquid level occurs in the cathode compartment, but great change of liquid level occurs in the anode compartment, and the electrolyte inside the anode compartment, under the action of electric fields, penetrates porous mid wall and permeates to the cathode compartment; furthermore, the liquid level difference between the cathode compartment and the anode compartment increases along with increase of the current density, showing that the electro-osmosis speed is proportional to the current density. EDX analysis has shown that the material osmosized to the cell wall is dominated by cryolite and sodium fluoride, with trace of sodium and aluminum, and the content of cryolite and sodium fluoride in the cathode wall is higher than that in the anode wall, indicating that the electrolyte is osmosized toward the cathode.