Antimony Recovery and Debromination of Flame-Retardant Electronic Waste Plastics

Antimony oxide is a common synergist for brominated aromatic flame retardants. These are combined in plastic housings for electronics from televisions to computers, as well as plastics used in transportation vehicles such as automobiles, ships and aircraft. Antimony is deemed a critical metal that is insufficiently mined to meet demands; hence, routes for its recovery are essential. Conventional pyrolysis results in substantial antimony loss and toxic emissions, whereas solvent-based recycling relies on time-consuming and hazardous sequential steps of debromination followed by antimony recovery. Here, we introduce isothermal-clamped flash Joule heating (IC-FJH), which generates a spatially isothermal reaction zone and enables simultaneous debromination and Sb recovery within seconds. Ultrafast isothermal heating stabilizes Sb predominantly as the metal, achieving a recovery yield of ~90% and a purity of >97%, reducing losses from vapor-phase transport and from residual solids. At the same time, IC-FJH achieves deep debromination, reducing toxic brominated organic species by 34 to 51%, compared to slow heating conditions. The toxic brominated organics were converted into inorganic streams, predominantly forming HBr with 83% recovery. By life-cycle assessment, IC-FJH reduces resource consumption by 72%, climate change burdens by 65%, water use by 80%, and polycyclic aromatic hydrocarbon formation by 100% compared to conventional pathways. Overall, IC-FJH offers a viable route for the sustainable recovery of antimony and the end-of-life management of e-waste, while advancing cleaner production and a circular economy.