In this study, a novel gemini-type benzimidazole ionic liquid [C₆BIM₂][NTf₂]₂ was synthesized for efficient extract gold(III) from hydrochloric acid medium. Firstly, a series of parameters (e.g., vibrating time, the extractant concentration, acidity and salinity) were optimized and obtained the optimal extraction condition. Under this condition, the extraction efficiency can reach 98.42%, along with the distribution ratio of 186.87. Through the response surface methodology (RSM) model optimization, the amount of [C₆BIM₂][NTf₂]₂ corresponding to different HCl concentration was determined for gold(III) extraction during actual operation. Then, verified the anion exchange mechanism with the aid of Job’s method, UV–vis, FT-IR and ¹³C NMR. Thermodynamic parameters were calculated and implied that the extraction reaction was an exothermic and spontaneous process. Furthermore, organic phase loaded with gold(III) was easy to be completely stripped by CS(NH₂)₂/ HCl solution and its extraction ability was kept constant after 5 cycles extraction experiments. Meanwhile, [C₆BIM₂][NTf₂]₂ has a superb ability to select gold(III) in the multi-metal solution. In general, [C₆BIM₂][NTf₂]₂ showed distinguished selectivity and extraction ability for gold(III) from secondary resources, which was claimed to be a promising new style extractant.

本研究合成了一种新型双子型苯并咪唑离子液体[C ₆ BIM ₂ ][NTf ₂ ] ₂，用于从盐酸介质中有效提取金(III)。首先，对一系列参数（如振动时间、提取剂浓度、酸度和盐度）进行优化，得到最佳提取条件。在此条件下，提取效率可达98.42%，分配比为186.87。通过响应面法（RSM）模型优化，[C ₆ BIM ₂ ][NTf ₂ ] _{2 量}在实际操作中确定了对应于不同 HCl 浓度的金（III）提取。然后，借助Job 法、UV-vis、FT-IR 和¹³ C NMR验证了阴离子交换机制。计算了热力学参数，表明萃取反应是一个放热和自发过程。此外，载有金(III)的有机相很容易被CS(NH ₂ ) ₂ / HCl溶液完全汽提，经过5次循环萃取实验后其萃取能力保持不变。同时，[C ₆ BIM ₂ ][NTf ₂ ] ₂在多金属溶液中具有极好的选择金(III)的能力。一般来说，[C ₆BIM ₂ ][NTf ₂ ] ₂显示出从次生资源中提取金（III）的卓越选择性和提取能力，被认为是一种很有前途的新型提取剂。