Screening dilute sources of rare earth elements for their circular recovery

Metals, including rare earth elements (REE), are the cornerstone of our current and future low-carbon urban infrastructure. This study looks at different waste resources contaminated materials present in setting as REE sources. Wastes other dilute sources such incineration ashes, sediments, mine tailings not only essential achieving a circular, carbon-neutral economy but may be most realistic one. E-waste, being concentrated waste, faces serious reservations regarding handling large-scale facilities, this is generally landfilled. In study, we analyzed total concentrations pH desorption curves ten REE: Ferrochrome slag from South Africa, sediments retrieved form stormwater ponds Denmark, coal fly municipal solid (MSW) wood bottom ashes sewage sludge (ashes sources). After analyzing residues, found that retention pond promising ones. While have highest critical contents studied wastes, collected showed leachability. We can find Nd, Dy, Er – all sediments/soils near highways, bauxite residue. Overall, contain wastes water leachable REE. fact, up to 100% these room temperature low pH. Future resource extraction efforts should account for speciation contents. • Residual, end-of-life (contaminated) Extraction recovery take into complexation wastes. Stormwater acid temperature. Coal