Molecular dynamic simulations of methane hydrate formation between solid surfaces: Implications for methane storage

Accurate determination of the wetting characteristics on mineral surfaces is critical for many natural processes and industrial applications where multiphase flow in porous media is involved. The wetting behaviors on mineral surfaces are controlled by water-mineral interactions, giving rise to various wetting characteristics, including contact line advancement, formation of precursor films, etc. However, a fundamental understanding of wetting characteristics on different mineral surfaces is still lacking at the molecular level. Here, utilizing a comprehensive set of molecular dynamics simulations, we investigate the wetting characteristics of water on various mineral surfaces and obtain the corresponding water-mineral interaction properties (including the areal density of water-mineral interaction energy and the work of adhesion of the water-mineral interface), mineral wettability, and structural and diffusion properties of water molecules near the surface. We show that the diffusion properties of water molecules on mineral surfaces play an important role in wetting characteristics. We find that the contact line tends to advance forward in the jumping mode or the rolling mode during the wetting process, which depends on the diffusion capacity of the water molecules on mineral surfaces. The corresponding evolution of the solid-liquid friction coefficient during dynamic spreading is also analyzed. We further demonstrate the strong impact of isomorphic substitution and charge-balancing counterions on wetting characteristics on the surfaces of clay minerals. It is shown that the introduction of charge-balancing counterions can shift the mineral surface from strongly hydrophilic to strongly hydrophobic and lead to completely different wetting characteristics. Our results provide a clearer picture of the molecular underpinnings in mineral wetting phenomena and deepen the understanding of the control of water-mineral interactions on the wetting properties.

Molecular Origin of Wetting Characteristics on Mineral Surfaces.

Editorial: Introduction to the Special Issue on Interface-Structural Materials for Catalysis and Energy

Adsorption layer of complex oil components in organic-rich shale: A molecular dynamics simulation study

Mechanism for the effects of surface chemical composition and crystal face on the wettability of α-quartz surface

Crystal face dependent wettability of α-quartz: Elucidation by time-of-flight secondary ion mass spectrometry techniques combined with molecular dynamics.

Water molecules confined in a microporous metal–organic framework (MOF) UiO-66 are characterized by a low-field 1H nuclear magnetic resonance (NMR) spectroscopy. Measurements are performed of the l...

Qianhong Wu

Papers

Crystal face dependent wettability of α-quartz: Elucidation by time-of-flight secondary ion mass spectrometry techniques combined with molecular dynamics.

Low-field 1H NMR relaxometry of water molecules confined in microporous UiO-66