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The supply issue of rare earth elements (REE) has become an increasingly important issue both economically and politically. Their industrial importance continues to increase while most production is located China, which makes the supply potentially vulnerable. As REE are vital for many important electronic products such as electric motors and hard drives, many nations have started looking for alternative supplies of these elements. One potential source that has garnered much attention in developed regions is REE-containing waste, mainly scrapped electronics. In regions such as the EU, electronic waste could in theory cover a significant part of the demand for REE. In addition, recycling of REE should be an important part of a circular economy, especially considering the large resource demands and negative environmental impact of current REE production processes. Though much research has been performed in the area, REE recycling is still very limited. Of the numerous methods for REE recycling from various waste fractions only a few have been tested in a larger scale. These large-scale recycling processes are either hydrometallurgical processes similar to those used in regular REE production or specific methods used to recycle pure waste fractions within a production facility. Most recycling processes that do not use an already pure feedstock aim to produce a REE-containing concentrate that can be fed into existing, commercially available REE separation processes. The dominant separation method is multiple stage solvent extraction; the only other method in commercial use is ion exchange, which is employed where especially high purity is required. REE recycling faces a number of challenges, such as the presence of contaminants in the feedstock, deficiencies in waste collection and processes requiring large amounts of energy and chemicals. The combination of REE recycling with recovery of other valuables from secondary raw materials is a possible synergy. The supply issue of rare earth elements (REE) has become an increasingly important issue both economically and politically. REE recycling faces a number of challenges, such as the presence of contaminants in the feedstock, deficiencies in waste collection and processes requiring large amounts of energy and chemicals. The combination of REE recycling with recovery of other valuables from secondary raw materials is a possible synergy. This report describes methods and synergies. |
