Antimony Trioxide Extraction from E-Waste Brominated Flame-Retardant Laden Plastics by Simultaneous Liquid–Liquid Extraction and Leaching

Abstract

A novel method for extracting antimony from electronic waste (e-waste) plastics was investigated in this work. Antimony trioxide is initially incorporated into these plastics in synergy with brominated molecules, hence their common name “brominated plastics”. This combination offers excellent flame-retardant properties. The mechanical recycling of brominated plastics is prohibited due to the hazardous nature of the molecules that are generated during the process. Therefore, this Review explores the use of a plastic dissolution method combined with liquid–liquid interfacial leaching to remove antimony trioxide while recovering a plastic cleansed of this problematic additive. The primary investigative focus pertained to the refinement of the aqueous extractant solution, while the secondary focus centered on the selection of the dissolution solvent. The process demonstrates high efficiency in antimony extraction, achieving up to 98 mass % recovery, with minimal impact on the structural integrity of the acrylonitrile–butadiene–styrene plastic. By insolubilization of the plastic to recover it, it is also feasible to recover up to 98 mass % of the brominated molecules, thereby ensuring compliance with legal thresholds for the reuse of plastics. This methodology not only addresses the challenge of safely recycling hazardous materials in e-waste but also offers insights for future enhancements in e-waste management and antimony recycling.