国家的“双碳”目标对铝冶炼工业提出了新要求。针对传统Hall-héroult法生产铝存在高能耗、高排放的问题,我国将严守电解铝4500万吨“天花板”,积极开发铝再生技术,2025年实现再生铝产量由2020年的690万吨增至1150万吨。不论是电解制铝还是铝的再生精炼都需要在高温下进行,亟需低碳节能新技术的开发。离子液体中铝的电沉积能在<100℃下进行,能耗大大降低,且没有二氧化碳以及其他污染气体的排放,有望发展成为铝工业生产的一种新型绿色工艺。本综述按照阳离子结构对用于铝电沉积的离子液体体系进行分类,分别论述了相关研究进展,总结了以不同铝基材料作为阳极在离子液体中电解精炼铝的研究。最后,概括了铝电沉积用离子液体电解质体系的特性,并指出了存在的一些问题。
In 2020, China has already committed to peak carbon dioxide emissions before 2030 and achieves carbon neutrality before 2060. Due to the high energy consumption and carbon emission of the traditional Hall-héroult method of the aluminum electrolysis process, China strictly adheres to the production ceiling of 45 million tons of aluminum and actively develops the recycling technology of aluminum, reaching the output of the recycled aluminum up to 11.5 million tons by 2025 from 6.9 million in 2020. At present, both electrolysis and refining of aluminum are processed at high temperature. Thus, the developments of energy saving processes are required. Electrodeposition of aluminum in ionic liquids can proceed at the temperature below 100℃, which is expected to develop into a novel green technique due to its less energy consumption and no emission of carbon dioxide or other pollutants. In this review, the ionic liquids used for aluminum electrodeposition are classified according to the structure of cations, and the related research progress is reviewed respectively. In addition, the application of different anodes with aluminum as main component in electrolytic refining of aluminum in ionic liquids is also summarized. Finally, the characteristics of ionic liquid electrolyte for aluminum electrodeposition are concluded and some existing problems are pointed out.