对水+气+固体系统在不同温度和压力下的流体-固体界面张力的分子洞察
Yafan Yang1,2, Jingyu Wan1, Xiangyu Shang1
1State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China.
The Journal of chemical physics
|September 1, 2023
概括
液体-固体界面张力对于地质资源回收和碳储存至关重要. 分子动力学模拟显示温度和压力显著影响界面张力,影响地质应用.
科学领域:
- 地质物理学 地质物理学
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 液体-固体界面张力对于温室气体的地质储存和增强地质资源回收至关重要.
- 了解这些特性对于优化地下过程至关重要.
- 然而,液体-固体界面行为尚未得到广泛研究.
研究的目的:
- 在多组件系统中研究液体-固体界面特性.
- 为了确定温度,压力和湿度对界面张力的影响.
- 为地质应用相关的界面现象提供见解.
主要方法:
- 进行了广泛的分子动力学 (MD) 模拟.
- 模拟涵盖了三相系统:H2O + 气体 (H2,N2,CH4,CO2) + 刚性固体.
- 条件各不相同:温度 (298403 K),压力 (0100 MPa) 和可湿性 (水友性,中性,疏水性).
主要成果:
- 当流体-固体相互作用强烈或接触角度接近90°时,蒸汽-固体界面张力是显著的.
- 温度上升降低H2O液体-固体界面张力,但增加H2O蒸气-固体界面张力.
- 在CH4或CO2系统中,压力显著影响H2O-固体的界面张力,但在H2或N2系统中没有影响.
- 气体-固体界面张力随着压力和气体-固体相互作用而增加,但随着温度升高而下降.
- 气体对接触角度的影响依次:H2 < N2 < CH4 < CO2.
结论:
- 界面张力行为是复杂的,高度依赖于系统组成,温度和压力.
- 在诺伊曼方法中假设压力独立的界面张力需要对具有强烈气体固体相互作用的非水友表面进行仔细考虑.
- 结果为建模和优化涉及流体-固体接口的地质过程提供了关键数据.
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