离子对CO2-盐水系统界面特性的影响  

Ion effect on interfacial properties of CO_2-brine system

作　　者：季佳圆 赵伶玲[1] 李偲宇 

机构地区：[1]东南大学能源与环境学院,能源热转换及其过程测控教育部重点实验室,江苏南京210096

出　　处：《化工学报》2017年第1期223-229,共7页CIESC Journal

基　　金：国家自然科学基金项目(51106027)~~

摘　　要：应用分子动力学模拟的方法对不同浓度及组分比例的CO_2-NaCl、CO_2-CaCl_2和CO_2-(NaCl+CaCl_2)等CO_2-盐水系统的界面张力进行了研究,从分子层面上分析了不同种类的盐离子对界面张力的影响。结果表明,盐离子的存在会增加CO_2-纯水的界面张力,界面张力增量主要由阳离子电荷数导致,其余则由阳离子兰纳-琼斯势参数、原子质量等原子特性参数引起;3种系统的界面张力增量均与离子强度呈线性关系,且其曲线的斜率和盐溶液种类无关,为IFT预测提供理论指导。Interfacial tension of CO2-NaCl, CO2-CaCl2 and CO2-（NaCl＋CaCl2） solution systems was studied at different salt concentration and ratio by molecular dynamics simulation, in order to understand influence of different salt ions at molecular level. The results showed that the presence of salt ions increased interfacial tension between CO2 and water, which majority was caused by number of cationic charges and the rest was by cation atomic properties such as Lennard Jones potential parameters and atomic mass. The interfacial tension increment of these three systems were all linearly dependent on ionic strength, but the slope had no relationship to types of salt solutions. This founding would provide theoretical guidance for IFT prediction.

关 键 词：CO2-盐水系统 界面张力 分子模拟 原子特性参数 离子强度 

分 类 号：TQ021.2[化学工程]