Potential low-cost electrochemical recycling of aluminum based on low-temperature AlCl₃–CO(NH₂)₂ electrolyte

Aluminum and aluminum alloys are basic metals widely used in the industry and efficient and upgraded recycling of aluminum alloys is critical to maintain aluminum quality for avoiding the final sink downgraded recycled and utilization. Up to date, the success of aluminum recycling is dependent on the degraded aluminum production based on high temperature and high energy consumption remelting process. To achieve a sustainable upgrading and low energy consumption process, electrochemical refining based on ionic liquid would be a potential strategy, while high cost of ionic liquids has substantially suppressed the industrial progresses. For addressing this issue, here a potential low-cost and low-temperature electrochemical refining of aluminum and aluminum alloys has been demonstrated via employing AlCl₃-CO(NH₂)₂ electrolyte. The optimal cathodes and electrolytes for electrochemical refining are confirmed, allowing for stable electrochemical operation at current density of 30 mA/cm² under temperature of 80℃. The electrochemical refining experiments suggest that such strategy is universal to electrochemical refining different types of aluminum alloys, and the purity of the as-refined aluminum at the cathodes exceeds 99.3wt%. The advantages of this study indicate a potential low-cost, low-temperature, and low-energy consumption strategy for upgrading and recycling spent aluminum and aluminum alloys.