LAUSR

Abstract In this paper, a novel ionic liquid ([ACh][Tf2N]) was synthesized and applied for gold separation from secondary resources, which can be employed as both hydrophobic phase and extractant in the extraction process. By modulating various parameters, the extraction behavior of gold(III) under various conditions was investigated. The result shows that it is more suitable for gold(III) extraction with high salinity and lower acidity, whereas the extraction efficiency can reach 98.98% in 5 min. The anion exchange mechanism between [ACh][Tf2N] and gold(III) was proved by UV–vis, FT-IR, 13C NMR and quantum chemical calculations. The gold(III) in organic phase was easily stripped by 1 mL 0.05 M CS(NH2)2/0.1 M HCl. [ACh][Tf2N] also possesses excellent selectivity for gold(III) in the mixed metal solutions. Furthermore, its operating conditions combination: ionic liquid dosage, the concentration of HCl and NaCl were optimized to 0.55 g, 0.5 M and 2.5 M by response surface methodology (RSM), respectively. Hence, the [ACh][Tf2N] was regarded as a potential extractant for gold recovery from secondary resources.