In this study, density was measured for hydrophilic deep eutectic solvents based on tetrabutylammonium bromide (as hydrogen bond acceptor) and glycerol (as hydrogen bond donor) in a 1:3 mol ratio with an aqueous heavy metal (Cu/Hg) solution at various concentrations in the temperature range of 298.15–348.15 K at atmospheric pressure. The excess molar volume, partial molar volume, excess partial molar volume, apparent molar volume, excess partial molar volume at infinite dilution, and isobaric expansivity were calculated to study the nonideal behavior of these pseudobinary systems. The obtained excess molar volumes (V_m^E) of 72 systems were then fitted to Redlich–Kister-type polynomial expressions. In addition, the performance of the predictive conductor-like screening model for real solvents (COSMO-RS) model is capable of quantitatively observing the sigma surface, sigma profile, and sigma potential of the individual chemical species and six prepared deep eutectic solvents. The existence of bands was analyzed for hydrogen bond acceptors (HBAs), hydrogen bond donors (HBDs), and used metal salts using Fourier transform infrared (FTIR) spectroscopy. Hydrophobic deep eutectic solvents (DESs) removed heavy metal (HM) ions from the synthetic contaminated water stream. At lower concentrations of Hg²⁺ ions, extraction efficiency showed a higher value of 98.85% with capric acid-based DESs. Similarly, the extraction efficiency for Cu²⁺ ions reached a maximum of 54.25% in this study. Before and after extraction, the concentrations of divalent copper and mercury were analyzed using inductively coupled plasma optical emission spectroscopy (ICP-OES).

中文翻译：

---

Cu(II) 和 Hg(II) 水混合物与{四丁基溴化铵 + 甘油 (1:3)} 低共熔溶剂的体积研究以及{四丁基溴化铵 + 癸酸/油酸} 对二价（Cu 和 Hg）的萃取性能重金属

在这项研究中，测量了基于摩尔比为 1:3 的四丁基溴化铵（作为氢键受体）和甘油（作为氢键供体）与重金属 (Cu/Hg) 水溶液在不同温度下的亲水性低共熔溶剂的密度。大气压下温度范围 298.15–348.15 K 的浓度。计算过量摩尔体积、偏摩尔体积、过量偏摩尔体积、表观摩尔体积、无限稀释时的过量偏摩尔体积和等压膨胀率，以研究这些伪二元系统的非理想行为。然后将获得的 72 个系统的过量摩尔体积 ( V _m ^E ) 拟合到 Redlich-Kister 型多项式表达式。此外，真实溶剂预测类导体筛选模型 (COSMO-RS) 模型的性能能够定量观察单个化学物质和六种制备的低共熔溶剂的西格玛表面、西格玛轮廓和西格玛电位。使用傅里叶变换红外 (FTIR) 光谱分析氢键受体 (HBA)、氢键供体 (HBD) 和使用的金属盐的带的存在。疏水性低共熔溶剂 (DES) 可去除合成污染水流中的重金属 (HM) 离子。在较低浓度的 Hg ²⁺离子下，基于癸酸的 DES 的萃取效率高达 98.85%。^{同样，本研究中Cu 2+}离子的萃取效率最高达到54.25%。萃取前后，使用电感耦合等离子体发射光谱法 (ICP-OES) 分析二价铜和汞的浓度。