China Nonferrous Metallurgy

Aluminum and aluminum alloys have strong corrosion resistance, very low loss and high recycling value. Promoting the recycling of spent aluminum can significantly reduce energy consumption and carbon emissions in the aluminum industry. In this paper, the process of downcycling, equivalent recycling and upcycling of spent aluminum is summarized, and the advantages and disadvantages of each process are analyzed. The traditional spent aluminum remelting degradation regeneration process can not completely remove the alloying elements and metal impurities in aluminum, recycled aluminum can only be degraded, but with the increase of recycled aluminum, the traditional degradation utilization technology will not be able to use so much recycled aluminum. Grade protection recycling can maximize the value of spent aluminum resources, but only a very small number of high-quality spent aluminum alloys can realize its inherent value, and it is difficult to achieve most of the spent aluminum resources. Spent aluminum Upcycling technology can separate aluminum and alloying elements, so that the recovered aluminum can reach the quality level of primary aluminum, and can realize the complete regeneration of spent aluminum, which is the best way to recycle waste aluminum. Molten salt electrolysis is the most promising technology for extracting aluminum from spent aluminum.