Recent strategies for aluminum production waste recovery: process, environmental impacts, and circular economy...

The primary production of aluminum generates hazardous solid residues, which collectively present a critical challenge involving both environmental toxicity and strategic resource depletion. Current industry reliance on secure landfilling fails to mitigate long-term risks posed by leaching of fluorides, heavy metals, and cyanide. This approach results in significant economic loss by preventing the recovery of essential aluminum and fluorine feedstocks. The high Na/Al impurity ratio and complex chemical composition of this waste severely limit recovery, making the reclaimed compounds unsuitable for purity-sensitive electrolytic reduction. Overcoming these chemical barriers requires a paradigm shift from simple waste stabilization to targeted, high-purity resource recovery to meet both economic and environmental objectives. This paper proposes an integrated upcycling strategy that combines a hydrometallurgical process with separation techniques (e.g., pyro-hydrometallurgy, solvent extraction, nanofiltration membrane) to achieve high-purity material recovery and minimize secondary hazardous wastewater. We critically evaluate the primary waste streams of aluminum production, detailing their transformation from hazardous byproducts into strategic resources. Ultimately, this integrated approach provides a circular economy roadmap that offsets the ecological risks of landfilling while restoring essential feedstocks to the primary production cycle.