A freestanding, hierarchically porous poly(imine dioxime) membrane enabling selective gold recovery from e‐waste with unprecedented capacity

Abstract

The ever-growing depletion of precious metals in modern electronic industry necessitates unremitting exploitation of novel materials for gold recovery from e-waste. Herein, a freestanding poly(imine dioxime) (PIDO) membrane has been successfully fabricated for highly efficient recovery of gold from e-waste. The consummate integration of abundant binding sites and hierarchically porous architecture renders the resulting PIDO membrane with a recordbreaking uptake capacity (9250 mg g À1 ) toward gold, fast adsorption equilibrium time, as well as satisfactory regeneration and reusability. Furthermore, PIDO membrane is also well competent for selective gold recovery from waste central processing unit leachate with remarkable efficiency (>99%). Considering high recovery efficiency, outstanding selectivity, and simple/scalable production process, the proposed PIDO membrane will hold huge prospect in the sustainable recovery of gold from e-waste.

Trash or treasure? Sustainable noble metal recovery

“…Wang et al 123 investigated the new redox reaction rejection mechanism of Au recovery from trace-level solution by the With its excellent multidentate ligand and high nitrogen content, amidoxime has attracted people's attention as a lowbudget adsorbent. Li et al 124 fabricated hierarchically porous poly(imine dioxime) (PIDO) membrane via an evaporationinduced self-assembly technique based on the Marangoni effect. The PIDO membrane exhibited a satisfactory uptake capacity (9250 mg g −1 ) for gold from e-waste, based on a combined adsorption/reduction mechanism.…”

“…Fig.8(a) Schematic diagram of π-π interaction between the MOF and the PU polymer and optimized geometries for the configuration of PU/ UiO-66 122. (b) Energy of binding (E bind ) in sequential adsorption of Au, Pt and Cu-based DFT calculations 124. (c) Schematic diagram of the spontaneous recovery between MoS 2 paper and gold ions 125.…”

Dual-Crosslinking Polydopamine/Poly(imide dioxime) Porous Network Membrane Enables Efficient and Selective Gold Recovery from e-Waste

“…In view of the higher correlation coefficient (0.9998) of the pseudo-secondorder kinetic model over that (0.6277) of the pseudo-firstorder model, the Au(III) adsorption on the PDA/PIDO membrane belongs to a chemical process. 40 Additionally, the kinetics data are also analyzed using an intraparticle diffusion model to identify the primary controlling factors during the adsorption process. As illustrated in Figure S8b, the intraparticle diffusion model also agrees well with the adsorption data, indicative of a multistage adsorption process.…”

Rapid and Selective Gold Stripping from Electronic Waste with Yolk–Shell-Structured Ion-Imprinted Magnetic Mesoporous Nanorobots for Efficient Water Decontamination

“…To date, various recovery techniques such as chemical precipitation, electrochemical techniques, solvent extraction, ion exchange, photocatalysis, membrane filtration, and adsorption have been developed to achieve gold recovery. Among them, adsorption has been recognized as a feasible and environmentally friendly strategy due to its easy operation, low cost, high efficiency, and green process .…”