Rising raw material and energy prices, export dependencies and supply risks strengthen the efforts for more efficient use of resources from an economic and raw material policy perspective. In view of the disproportionate increase in copper demand in the coming years, which will result above all from the rapid expansion of the renewable energies and e-mobility sectors, copper and copper alloy scrap represent an important source of raw materials for the metal-producing industry. The recycling of unsorted scrap takes place predominantly in the copper smelter, where copper and the alloying elements are recovered pyrometallurgically in a multi-stage and comparatively energy-intensive process. If, on the other hand, the scrap is sorted into distinct alloy types, it can be remelted with significantly lower energy and material consumption. This reduces metal losses, saves resources and minimizes CO2 emissions and melting costs. In practice, sorting by type has been carried out up to now exclusively manually with the aid of handheld analyzers and is generally only economical for larger piece sizes. However, there is a lack of automated sorting applications with which comparable purities to manual sorting can be achieved.

Against this background, the recovery of more precisely specified alloy groups was tested on a mixture of copper and copper alloy scrap using an x-ray fluorescence (XRF)-based sorting system in large-scale trials. Through a targeted adjustment of the classification methodology, the common main alloy groups standardized for material production (e.g. brass, red brass, aluminum bronze etc.) and low-alloyed copper could be systematically enriched in the sorting products.