Current efficiency of recycling aluminum from aluminum scraps by electrolysis  

电解废旧铝合金回收铝的电流效率(英文)

作　　者：徐君莉[1] 张净[2] 石忠宁[3] 高炳亮[3] 王兆文[3] 胡宪伟[3] 

机构地区：[1]东北大学理学院,沈阳110819 [2]中冶华天工程技术有限公司,马鞍山243005 [3]东北大学材料冶金学院,沈阳110819

出　　处：《Transactions of Nonferrous Metals Society of China》2014年第1期250-256,共7页中国有色金属学报（英文版）

基　　金：Projects(51104042,51074046)supported by the National Natural Science Foundation of China;Project(N120405006)supported by the Fundamental Research Funds for the Central University,China

摘　　要：Extracting aluminum from aluminum alloys in AlCl3-NaCl molten salts was investigated. Al coating was deposited on the copper cathode by the method of direct current deposition using aluminum alloys as anode. The purity of the deposited aluminum is about 99.7% with the energy consumption of 3-9 kW＆#183;h per kg Al, and the current efficiency is 44%-64% when the deposition process is carried out under 100 mA/cm2 for 4 h at 170 ＆#176;C. The effects of experimental parameters, such as molar ratio of AlCl3 to NaCl, cathodic current density and electrolysis time, on the current efficiency were studied. The molar ratio of AlCl3 to NaCl has little effect on the current efficiency, and the increase of deposition temperature is beneficial to the increase of current efficiency. However, the increase of current density or electrolysis time results in the decrease of current efficiency. The decrease of current efficiency is mainly related to the formation of dendritic or powder deposit of aluminum which is easy to fall into the electrolyte.研究在 AlC13-NaCl熔融盐体系中进行电精炼废旧铝合金回收金属铝。以铝合金为阳极，通过直流电沉积在铜阴极上得到铝涂层。在170＆#176;C、电流密度100 mA/cm2下电解4 h，得到的沉积物铝的纯度大约为99.7%，电流效率为44%~64%，每千克铝消耗电能3~9 kW＆#183;h。探讨阴极电流密度、电解质成分和电解时间及温度等对铝沉积电流效率的影响。结果表明：在AlCl3和NaCl摩尔比为1.3~1.9时，AlCl3和NaCl摩尔比对电流效率的影响很小，升高电解温度有利于提高电流效率；但是延长电解时间或增大电流密度会导致电流效率降低。电流效率的降低主要是由于沉积的铝呈现枝状晶或粉化而易从阴极上脱落到电解质中所致。

关 键 词：aluminum recycling aluminum alloy current efficiency ELECTROLYSIS chlorides molten salts 

分 类 号：X705[环境科学与工程—环境工程]