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A non-solvent-induced phase separation method was used to synthesize easily separable membrane materials from polyether sulfone and polym-phenylenediamine to achieve selective recovery of Au from e-waste solutions. The optimum conditions, adsorption capacity, and selectivity of the polyether sulfone/polym-phenylenediamine membrane were investigated by adsorption experiments. The maximum adsorption capacity of the PES/PmPD membrane to Au(III) within 4 h at 30 °C with optimal pH of 1 was 582.75 mg/g. The adsorption process follows the quasi-second-order adsorption isotherm. The adsorption agent was characterized by XPS and XRD to understand the recovery mechanism of Au(III) by PES/PmPD membrane. In addition, PES/PmPD membranes were single-selective for Au(III) in a variety of natural water bodies and highly acidic conditions. Therefore, the thin membrane material has great potential for recycling Au(III) from waste e-waste. • A kind of macro polyether sulfone/polym-phenylenediamine(PES/PmPD) membrane material was prepared. • PES/PmPD membrane has high selectivity for gold in e-waste solution. • The treatment capacity of PES/PmPD membrane for Au(III) reaches 582.75 mg/g. • PES/PmPD membrane can be regenerated by simple solution washing. [ABSTRACT FROM AUTHOR]

Poly(m-phenylenediamine) has a wide range of applications in adsorption due to its high amino content; however, its nanoparticles tend to aggregate in water and are not easily separated from aqueous solutions. In this research, a soft and easily separable adsorbent material was successfully prepared by cross-linking poly(m-phenylenediamine) and chitosan through hydrogen bonding. Experimental results showed that the prepared chitosan and poly(m-phenylenediamine) hybrid membrane (CS/PmPD) could selectively reduce Au(III) from a mixture of multiple metal ions (Cu2+, Zn2+, Ni2+, Cd2+, and Au(III)). The maximum treatment capacity of Au(III) reached 410 mg g−1 under optimal adsorption conditions (pH = 3.0 and adsorption time of 120 min). The CS/PmPD membrane can be regnerated after rinsing with sodium bisulfite solution, and its performance remains stable after multiple cycles. In addition, the membrane has achieved satisfactory results in treating the actual CPU gold-containing leachate. Therefore, the CS/PmPD membrane has a promising application in gold recovery from electronic wastes. [ABSTRACT FROM AUTHOR]

To quickly and efficiently recover precious metal gold from electronic waste products, we synthesized a novel hollow polym‐phenylenediamine (PmPD) nanosphere using the sacrificial template method and applied this materials to reduce and recover Au(III) in an aqueous solution. Experimental results show that the as‐prepared hollow PmPD has high selectivity and treatment capacity for Au(III), and can selectively reduce Au(III) from mixture metals solutions, including Cu2+, Zn2+, Ni2+, Cd2+, and Au(III) mixed solutions. Under room temperature and solution pH 4.0, the maximum treatment capacity of hollow PmPD for Au(III) reaches 1185.18 mg/g in 10 min of equilibrium time. The reduction ability of hollow PmPD remains stable in a pH range of 1.0 to 10.0 and under an ambient temperature ranging from 0 °C to 50 °C. Hollow PmPD can be regenerated via simple NaHSO3 solution washing, and its performance remains stable after repeated recycling. The satisfactory results obtained in treating the computer CPU leaching solution suggest that the hollow PmPD has broad application prospects in recovering gold from e‐waste. [ABSTRACT FROM AUTHOR]