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The recovery of valuable gold from wastewater is of great interest because of the widespread use of the precious metal in various fields and the pollution generated by gold-containing wastes in water. In this paper, a water-insoluble cross-linked adsorbent material (TE) based on cyanuric chloride (TCT) and ethylenediamine (EDA) was designed and used for the adsorption of Au(III) from wastewater. It was found that TE showed extremely high selectivity (D = 49,213.46) and adsorption capacity (256.19 mg/g) for Au(III) under acidic conditions. The adsorption rate remained above 90% eVen after five adsorption–desorption cycles. The adsorption process followed the pseudo-first-order kinetic model and the Freundlich isotherm model, suggesting that physical adsorption with a multilayer molecular overlay dominates. Meanwhile, the adsorption mechanism was obtained by DFT calculation and XPS analysis, and the adsorption mechanism was mainly the electrostatic interaction and electron transfer between the protonated N atoms in the adsorbent (TE) and AuCl4−, which resulted in the redox reaction. The whole adsorption process was the result of the simultaneous action of physical and chemical adsorption. In conclusion, the adsorbent material TE shows great potential for gold adsorption and recovery. [ABSTRACT FROM AUTHOR]

Abstract: A new LiMnPO4 based material, LiMn0.8Fe0.19Mg0.01PO4/C, is synthesized by a solid state method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical test. The obtained LiMn0.8Fe0.19Mg0.01PO4 crystals with 8wt.% carbon coating are mainly 100–500nm in size, and aggregate into microparticles around 3–5μm. The electrochemical test demonstrates that the obtained LiMn0.8Fe0.19Mg0.01PO4/C has high capacity, good cycleability and quite excellent rate capability in spite of its larger size and less carbon coating as compared to those reported in the previous works. When discharged at a high rate of 10C, the obtained LiMn0.8Fe0.19Mg0.01PO4/C can still deliver a capacity of 115mAhg−1. The results prove that the LiMn0.8Fe0.19Mg0.01PO4/C is a very promising cathode material for lithium ion batteries. [Copyright &y& Elsevier]