Kumar Kishant, Bharti Anand, Mogurampelly Santosh
Department of Chemical Engineering, National Institute of Technology Warangal, Warangal, Telangana, India, 506004.
Department of Chemical Engineering, Birla Institute of Technology Mesra, Ranchi, Jharkhand, India, 835215.
J Mol Model. 2022 Jan 7;28(2):30. doi: 10.1007/s00894-021-05017-3.
Deep eutectic solvents (DESs) emerged as green solvents for new generation technologies owing to their high chemical and thermal stability. Addition of restricted amount of organic solvents into the DESs plays a significant role in the improvement of thermodynamic and the transport properties to work as a potential solvent in process industries. In this paper, molecular dynamics (MD) simulations were performed to understand the thermophysical and transport properties of choline chloride-based DES (reline) and primary alcohol (methanol and ethanol) mixture in relation to microscopic structure. Density, radial distribution function, coordination number, average number of H-bond, diffusion coefficient and spatial distribution function was calculated in order to understand the structure and involvement of H-bond network at an atomic level. H-bond and spatial distribution function analyses revealed that the chloride ion prefers to be spatially distributed around hydroxyl group of alcohol and found to be more pronounced upon increase in alcohol concentration. As a consequence, it was observed that the H-bonds between Cl and urea decreases overall with the loading of alcohol and effect is more pronounced beyond a concentration of 0.4. Self-diffusion values for choline, Cl and urea were found to be increased significantly upon increase in concentration of alcohol from 0.6 to 0.8. Overall, our simulation points to the interplay and interactions between the chloride ions and the solvents in determining the structural and transport properties of choline chloride-based DES.
由于其高化学稳定性和热稳定性，深共熔溶剂（DESs）作为新一代技术的绿色溶剂而出现。向DESs中添加适量的有机溶剂对于改善热力学和传输性质起着重要作用，使其能够在过程工业中作为潜在溶剂使用。在本文中，进行了分子动力学（MD）模拟，以了解基于氯化胆碱的DES（reline）与伯醇（甲醇和乙醇）混合物的热物理和传输性质与微观结构之间的关系。计算了密度、径向分布函数、配位数、氢键平均数、扩散系数和空间分布函数，以便在原子水平上了解氢键网络的结构和参与情况。氢键和空间分布函数分析表明，氯离子倾向于在醇的羟基周围进行空间分布，并且随着醇浓度的增加，这种现象更加明显。因此，可以观察到，随着醇的加入，Cl与尿素之间的氢键总体上减少，并且在浓度超过0.4时，这种影响更加明显。当醇的浓度从0.6增加到0.8时，发现胆碱、Cl和尿素的自扩散值显著增加。总体而言，我们的模拟表明，氯离子与溶剂之间的相互作用和相互影响决定了基于氯化胆碱的DES的结构和传输性质。
