蒙脱石(001)晶面水化作用的分子动力学模拟  

Molecular dynamics simulations to the hydration of montmorillonite surface(001)

作　　者：戴敏 刘炳鑫 肖纯 卞恒智 荣嵘 彭昌盛 DAI Min;LIU Bing-xin;XIAO Chun;BIAN Heng-zhi;RONG Rong;PENG Chang-sheng(School of Environmental and Chemical Engineering,Zhaoqing University,Zhaoqing 526061,China;College of Environmental Science and Engineering,Ocean University of China,Qingdao 266100,China;School of Chemical and Environmental Engineering,Anhui Polytechnic University,Wuhu 241000,China)

机构地区：[1]广东省环境健康与资源利用重点实验室,肇庆学院环境与化学工程学院,广东肇庆526061 [2]中国海洋大学环境科学与工程学院,山东青岛266100 [3]安徽工程大学化学与环境工程学院,安徽芜湖241000

出　　处：《化学研究与应用》2025年第3期624-630,共7页Chemical Research and Application

基　　金：广东省普通高校创新团队项目(2021KCXTD005)资助。

摘　　要：通过分子动力学模拟,探究了环境温度、离子种类、浓度和表面电荷对蒙脱石表面水化作用的影响。模拟结果显示,温度由280 K升至330 K,蒙脱石表面水化膜密度及蒙脱石与水分子之间的吸附能逐渐降低,水分子的自扩散系数逐渐增加,但水化膜的厚度基本没有变化;阳离子与水分子在蒙脱石表面存在竞争吸附,离子的加入增加了蒙脱石表面水化膜的厚度,但降低了水化膜的密度,而且水化膜出现位置后移现象。二价阳离子与蒙脱石的相互作用大于一价阳离子,离子浓度的增加会降低蒙脱石与水分子的吸附能。表面电荷对蒙脱石表面水化作用的影响最为显著,蒙脱石与水分子之间的吸附能随表面电荷的升高而增大,水化膜厚度也从1.11 nm升高至1.44 nm,增加约30%。The molecular dynamics simulations were used to explore the effects of temperature,ion species and concentration,and surface charge on the hydration of montmorillonite.The results show that the density of the hydration layers on the montmorllonite surface and the adsorption energy between montmorllonite and water molecules gradually decrease with the increasing temperature from 280 K to 330 K,while the self-diffusion coefficient of water molecules gradually increases.The thickness of the hydration layers remains at 1.11 nm.Cations and water molecules have competitive adsorption on the surface of montmorillonite.The addition of cations increases the thickness but decreases the density of the hydration layers of montmorillonite.The hydration film position is shifted back.The interaction between montmorillonite and divalent ions is stronger.The increase in ion concentration decreases the adsorption energy between montmorillonite and water molecules.The surface charge has the most significant effect on the surface hydration of montmorillonite.The adsorption energy between water molecules and montmorillonite increases with the increasing surface charge.The thickness of the hydration film increases from 1.11 nm to 1.44 nm with an increase of about 30%.

关 键 词：蒙脱石 水化膜 影响因素 分子模拟 吸附能 

分 类 号：TQ170.12[化学工程—硅酸盐工业]