不同类型表面活性剂在石英表面和油/水界面吸附行为的分子动力学模拟

低渗透油藏开采中表面活性剂在岩石和油/水界面的吸附对岩石表面和油/水界面性质的影响,是低渗透油藏渗吸增强驱油技术的关键问题.本文运用分子动力学模拟方法研究了十八烷基二甲基羟丙基磺基甜菜碱(OHSB)、聚氧乙烯辛基苯酚醚-10(OP-10)、阳离子双子表面活性剂(12-4-12)、十二烷基苯磺酸钠(SDBS)和鼠李糖脂(...

Molecular Dynamics Simulation of Adsorption Behavior of Different Surfactants on Quartz Surface and Oil/water Interface

The adsorption behavior of surfactants on the rock and oil/water interface and its influence on the properties of the rock surface and the oil/water interface are the key issues in producing low permeability reservoirs of imbibition enhanced oil displacement technology in low permeability reservoirs. In this paper, molecular dynamics simulation methods are used to study the octadecyl dimethyl hydroxypropyl sultaine (OHSB), polyoxyethylene octyl phenol ether-10 (OP-10), Gemini surfactant (12-4-12), sodium dodecylbenzene sulfonate (SDBS), and rhamnolipid (RH-2DA), five types of surfactants adsorption behavior of on the quartz (101) surface and the oil/water interface. The study results show that among the five surfactants, the electrostatic attraction between the Gemini surfactant12-4-12 and the negatively charged quartz surface is the strongest, and the electrostatic repulsion between the SDBS and the quartz surface is the strongest. 12-4-12 and RH-2DA can spontaneously adsorb on the quartz surface and reduce the wettability of the quartz surface. The adsorption energy of five surfactants on the quartz surface from small to large is 12-4-12 < RH-2DA < OHSB < OP -10 < SDBS. All five surfactants can be adsorbed on the surface of the oil phase spontaneously, and the order of adsorption strength on the surface of the oil phase is OP-10 > RH-2DA > OHSB > 12-4-12 > SDBS. The adsorption of the five surfactants at the oil/water interface can all enhance the oil/water interface's stability.