State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, Hebei, 066004, PR China; School of Electrical Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, PR China.
School of Electrical Engineering, Yanshan University, Qinhuangdao, Hebei, 066004, PR China.
Chemosphere. 2023 Jan;311(Pt 1):137011. doi: 10.1016/j.chemosphere.2022.137011. Epub 2022 Oct 27.
In this article, molecular dynamics simulations were used to examine the feasibility of capacitive deionization (CDI) system combined with a functionalized nanoporous graphene (NPG) membrane for removing methanol from water. The radial distribution function of electrode-methanol and methanol-water, the self-diffusion coefficient of methanol and water, the water density near the membrane, the interaction energy between methanol and membrane, the hydrogen bond structure between methanol and water, and the 2D density map of methanol molecules near the membrane under different electric field (EF) (to simulate the effect of capacitance) were examined to evaluate the separation performance of NPG membranes with hydrogen-passivated pores for methanol. The findings show that an EF with appropriate strength can decrease the amount of water molecules near methanol, increase the self-diffusion coefficient of methanol and water, increase hydrophobicity of hydrogenated pores, decrease the interaction between the NPG membrane and methanol, and weaken hydrogen bond interaction between water and methanol molecules. All these findings suggest that an appropriate EF can improve the NPG membrane's permeability to methanol, and verify the feasibility of CDI system combined with hydrogenated NPG membrane to remove methanol from water. This study is expected to propose a potential CDI application technology, and also give a novel idea for the removal of small organic molecules in water by functionalized NPG membrane.
本文采用分子动力学模拟研究了功能化纳米多孔石墨烯（NPG）膜与电容去离子（CDI）系统结合去除水中甲醇的可行性。考察了电极-甲醇和甲醇-水的径向分布函数、甲醇和水的自扩散系数、膜附近的水密度、甲醇与膜之间的相互作用能、甲醇与水之间氢键结构以及不同电场（EF）（模拟电容效应）下膜附近甲醇分子的二维密度图，以评估具有氢化孔的 NPG 膜对甲醇的分离性能。研究结果表明，适当强度的 EF 可以减少甲醇附近的水分子数量，增加甲醇和水的自扩散系数，增加氢化孔的疏水性，降低 NPG 膜与甲醇之间的相互作用，并减弱水分子和甲醇分子之间的氢键相互作用。所有这些发现表明，适当的 EF 可以提高 NPG 膜对甲醇的渗透性，验证了 CDI 系统与氢化 NPG 膜结合去除水中甲醇的可行性。本研究有望提出一种潜在的 CDI 应用技术，也为功能化 NPG 膜去除水中小分子提供了新的思路。
