The effective and environmentally friendly recovery of gold from secondary resources has recently received increased attention. Hydrophobic deep eutectic solvent (HDES) composed of ,-di-butylacetamide and 1-decanoic acid was used to construct the liquid-liquid extraction system to extract Au(III) from HCl medium. At first, DSC, TGA, FT-IR, and H NMR were used to describe the evidence of internal hydrogen bond interaction. The above evidence was verified in the molecular dynamics study of HDES. Then, a series of optimization experiments were carried out to investigate the extraction behaviors of HDES. Based on the results of optimization experiments, response surface method was used to explore the best experimental conditions and the results showed that HDES extracted 99% Au(III) under 0.56 mol/L HCl, 2.19 mol/L NaCl, and 5.83 mmol/L Au(III), and the maximum loading reached 77.0 mg/g. Further studies on the kinetics and thermodynamics of the extraction were used to propose an ion association mechanism. In addition, using 0.1 mol/L thiourea as the stripping agent, HDES displayed outstanding Au(III) selectivity and maintained the extraction efficiency in tests which involved 5-cycles. Overall, this study provides a green and efficient Au(III) recovery strategy for secondary resources.

中文翻译：

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二丁基酰胺疏水性低共熔溶剂用于从盐酸介质中选择性萃取 Au(III)


从二次资源中有效且环保地回收黄金最近受到越来越多的关注。采用由 ,-二丁基乙酰胺和 1-癸酸组成的疏水性低共熔溶剂 (HDES) 构建液-液萃取体系，从 HCl 介质中萃取 Au(III)。最初，DSC、TGA、FT-IR 和 H NMR 被用来描述内部氢键相互作用的证据。上述证据在HDES的分子动力学研究中得到了验证。然后，进行了一系列优化实验来研究 HDES 的提取行为。根据优化实验结果，采用响应面法探索最佳实验条件，结果表明，HDES在0.56 mol/L HCl、2.19 mol/L NaCl和5.83 mmol/L条件下提取99% Au(III)。 Au(III)，最大负载量达到 77.0 mg/g。对萃取动力学和热力学的进一步研究提出了离子缔合机制。此外，使用0.1 mol/L硫脲作为反萃剂，HDES表现出出色的Au(III)选择性，并在涉及5个循环的测试中保持了萃取效率。总体而言，本研究为二次资源提供了绿色高效的Au(III)回收策略。