Interfacial Tension and Liquid Viscosity of Binary Mixtures of n-Hexane, n-Decane, or 1-Hexanol with Carbon Dioxide by Molecular Dynamics Simulations and Surface Light Scattering
Interfacial Tension and Liquid Viscosity of Binary Mixtures of n-Hexane, n-Decane, or 1-Hexanol with Carbon Dioxide by Molecular Dynamics Simulations and Surface Light Scattering
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DOI：
10.1007/s10765-019-2544-y
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发表时间：
2019-07
影响因子：
2.2
通讯作者：
T. Koller;Shaomin Yan;Corina Steininger;Tobias Klein;A. Fröba
中科院分区：
文献类型：
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作者：
T. Koller;Shaomin Yan;Corina Steininger;Tobias Klein;A. Fröba
用分子动力学(MD)模拟和表面光散射(SLS)研究了正己烷、正庚烷和正己醇与二氧化碳(CO2)二元混合物的界面张力和液体粘度。应用后一种技术，实验研究了溶解CO2对正己烷与CO2二元混合物界面张力和液体粘度的影响，实验温度为303.15℃，饱和压力高达5 Mpa，对应于液相中CO2摩尔分数高达0.75时。在汽液平衡条件下，测定了该体系的液体粘度和界面张力，平均相对扩展不确定度(k= 2)分别为1.8%和1.3%。在正己烷、正庚烷或正己醇与二氧化碳的二元混合物的平衡MD模拟中，预测了CO_2摩尔分数在(303.15,333.15和363.15)℃至0.52时的汽液平衡，包括饱和密度和界面张力。对于正己烷和二氧化碳的二元混合物，粘度和界面张力的测量数据与模拟数据吻合较好。通过分子动力学模拟，研究了链长和羟基化对界面张力的影响。模拟结果表明，表面张力越大的溶剂，气液界面上CO2的浓缩程度越明显。
In the present study, the interfacial tension and liquid viscosity of binary mixtures ofn-hexane,n-decane, or 1-hexanol with carbon dioxide (CO2) were investigated by molecular dynamics (MD) simulations and surface light scattering (SLS). The latter technique was applied to study experimentally the influence of dissolved CO2on the interfacial tension and liquid viscosity of binary mixtures ofn-hexane with CO2at 303.15 K and saturation pressures up to 5 MPa corresponding to a CO2mole fraction in the liquid phase up to 0.75. For this system at vapor–liquid equilibrium, the liquid viscosity and interfacial tension were determined with average relative expanded uncertainties (k= 2) of (1.8 and 1.3) %. In equilibrium MD simulations for binary mixtures ofn-hexane,n-decane, or 1-hexanol with CO2, the vapor–liquid equilibria including saturated densities as well as the interfacial tensions were predicted at temperatures of (303.15, 333.15, and 363.15) K for CO2mole fractions in the liquid phase up to 0.52. For the binary mixtures ofn-hexane with CO2, agreement between the measured and simulated data for viscosity and interfacial tension was found. With the three mixtures investigated by MD simulations, the influence of chain length and hydroxylation on the interfacial tension could be demonstrated. The simulations showed that the magnitude of CO2enrichment at the vapor–liquid interface is more pronounced for solvents with larger surface tensions.