Modification of leather debris with poly(p-phenylenediamine) for selective and effective gold(III) adsorption

The recovery of gold from electronic waste (e-waste) is essential for the efficient use of resources and has a positive impact on environmental protection. One effective method for recovering gold from e-waste leachate is through adsorption. To enhance this process, it is crucial to develop efficient and environmentally friendly adsorbents with high selectivity. Herein, we employed a “Treat waste with waste” strategy by developing a novel biomass adsorbent for gold recovery from e-waste leachate. The adsorbent, named PpPD-LF, is poly(p-phenylenediamine)-modified leather fiber fabricated from leather debris. The adsorbent demonstrated excellent adsorption capabilities for Au(III), with a maximum capacity of 1061 mg g⁻¹, alongside good selectivity against other coexisting ions. Notably, PpPD-LF can also directly reduce Au(III) to Au(0) because of the reduction sites present on the leather fiber and PpPD. This work introduces a sustainable and efficient way to handle waste, which has significance for environmental protection, economic cost-saving, and social sustainable development.