非水相液体（NAPLs）的多介质界面行为与迁移转化是当前环境化学领域研究的重点和难点。本项目聚焦于NAPLs污染场地的表面活性剂强化修复过程，从微观尺度上研究NAPLs在土壤-水界面的行为、迁移及力学机理。具体地，①研究NAPLs在土壤-水界面的润湿-去润湿行为、NAPLs乳滴的吸附-脱附行为，考察表面活性剂、环境介质等对NAPLs微观界面行为的影响；②采用表面力分析仪等手段测量NAPLs-土壤、表面活性剂-NAPLs之间的水下相互作用力，结合理论计算和分子模拟，剖析NAPLs-土壤-水相互作用机理，揭示NAPLs微观界面行为内在机制；③结合实验和仿真模拟，研究NAPLs乳滴在土壤-水多孔介质微环境中的迁移行为，建立NAPLs迁移动力学模型，阐明NAPLs界面行为与迁移的内在联系。本项目预期成果可为阐明NAPLs在土壤-水界面的微观界面行为、迁移及力学机理提供方法学基础和实验理论依据。

Multi-media interfacial behavior, transport and transformation of non-aqueous phase liquids (NAPLs) are the key issues in the field of environmental chemistry. In this proposal, we focus on removal of NAPLs from aquifer by surfactant-enhanced remediation, and plan to investigate the micro-scale interfacial behavior and transport of NAPLs at the soil-water system and the corresponding mechanical mechanism. Specifically, 1) we plan to study the wetting-dewetting behavior of NAPLs at the soil-water interface, the adsorption-desorption behavior of NAPLs emulsion droplets at the soil-water interface. The effects of surfactants and environmental media (e.g., soil, water) on the micro scale interfacial behavior of NAPLs will be investigated; 2) we plan to measure the underwater interaction force between NAPLs and soil (NAPLs-soil), and surfactant-NAPLs by surface force apparatus (SFA). According to the experimental results, together with the theoretical calculation and molecular simulation, we try to understand the mechanism of NAPLs-soil-water interaction and thus reveal the intrinsic mechanism on micro-scale interfacial behavior of NAPLs; 3) Combined with experimental research and analogue simulation, we plan to study the transport behavior of NAPLs emulsion droplets in the soil-water porous media (micro-environment), establish the transport dynamics model of NAPLs, and thus make clear the intrinsic relationship between the micro-scale interfacial behavior and transport of NAPLs. The results of this project will provide the methodology and the experimental and theoretical evidences for illustrating the micro-scale interfacial behavior, transport and mechanical mechanism of NAPLs at the soil-water interface.