Aluminum in particular is highly sought after as a scrap metal. Because it is both lightweight and strong, it’s used everywhere from drinks cans to aero planes. Extracting aluminum from its ore, bauxite, is relatively expensive, but salvaging it from scrap uses just five per cent of the energy needed to make new aluminum.
Like plastic bottles, a large percentage of recycled aluminum comes from beverage containers. The process is similar to plastics too. Once 
collected, they’re separated from the other metals by an eddy current separator that splits the non-ferrous aluminum with a powerful magnet. The aluminum is shredded into pieces of uniform size, mechanically cleaned then pressed into blocks to minimize oxidation.
The blocks are loaded into a furnace and heated to around 750 degrees Celsius (1,380 degrees Fahrenheit), at which point it becomes molten. The melted-down aluminum produces a surface scum known in the industry as dross, which is removed, before high-purity aluminum is added to bring the molten aluminum up to the required grade. The furnace is then rolled onto its side and the liquid aluminum poured out. The end product is either atomized aluminum powder or ingots. Because aluminum isn’t transmuted by this process, it’s just as good as the new stuff and can be recycled indefinitely.
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