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Cobalt is a widely used technology-enabling metal that is dominantly recovered as a by-product of copper and nickel. However, mainly because of its economic importance and high supply risks, it is classified as a critical raw material in Europe, increasing the importance of the utilization of secondary cobalt resources. This work presents a study of the recovery of a pure form of cobalt oxalate from spent low-grade VHS videotapes (0.35 wt% of cobalt). Firstly, depolymerization of the videotape was conducted by alkaline hydrolysis resulting in 94.5% polyethylene (PET) depolymerization yield (T = 150 °C, p = 6.9 bar, [NaOH] = 1 mol L^-1). Secondly, metal-rich residue (2.3 wt% of cobalt, 54.5 wt% of iron) of alkaline hydrolysis was subjected to hydrometallurgical leaching in two acids (H₂SO₄ and H₃PO₄) at 1 M (S/L = 10 g L⁻¹, t = 5 min, T = 80 °C). In the subsequent oxalate precipitation study, 99.9% purity and 98.0 …