An evaluation of neodymium‑iron‑boron permanent magnets (NdFeB PMs) from different end-of-life products, as a secondary resource of rare-earth elements (REEs), is presented. De-coating of PM was investigate as pre-treatment to facilitate efficient direct magnet recycling. Thus, critical aspects from disassembling to the de-coating of the magnets were addressed. A challenge for the de-coating process is that the magnets have different sizes, weights, and their coating compositions are not known beforehand. It was shown that ammonia-based solutions was thermodynamically suitable to dissolve nickel and zinc coatings selectively, while keeping the bulk magnet stable. Nevertheless, the dissolution of Zn was much faster than the Ni one, and more efficient.

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The demand for lithium-ion batteries (LiBs) is rising, resulting in a growing need to recycle the critical raw materials (CRMs) which they contain. Typically, all spent LiBs from consumer electronics end up in a single waste stream that is processed to produce black mass (BM) for further recovery. It is desired to design a recycling process that can deal with a mixture of LiBs. Hence, this study investigates the structure and composition of battery modules in common appliances such as laptops, power banks, smart watches, wireless earphones and mobile phones. The battery cells in the module were disassembled into cell casing, cathode, anode and separator. Then, the cathode active materials (CAMs) were characterized in detail with XRD-, SEM-, EDX- and ICP-OES-analysis. No direct link was found between the chemistry of the active materials (NMC, LCO, LMO, LFP etc.) and the application. Various BM samples were submitted to a leaching procedure (2 M H2SO4, 50 °C, 2 h, 60 g BM/L) with varying concentration (0–4 vol%) of H2O2 to study the influence of their chemical composition on the dissolution of Li, Ni, Mn and Co. Only a part of the BMs dissolved completely at 4 vol% H2O2, which was attributed to the oxidation state of the transition metals (TMs). Exact determination of H2O2 consumption by redox titration confirmed this hypothesis.@en