Abstract
The strong incentives to increase the total share of recycled aluminium in new products create challenges in the remelting chain to maintain control of alloying elements in the final products. Efficient and improved sorting of scrap has enabled good utilization of scrap from various sources; however, the sorting also yields a significant stream of scrap with alloy contents not suitable for remelting. Today this scrap is discarded, but it should rather be purified and used in remelting. The principles of the Hoopes cell for producing high-purity aluminium was adapted in a laboratory cell with completely new geometry and optimized for high throughput and a purity like primary aluminium metal. 99.5% pure Al was achieved from highly alloyed scrap sources with less than 5 kWh/kg energy usage and no CO₂ emissions. The process can remove any alloying elements.