Research on coal wettability and CH4 adsorption/desorption and diffusion characteristics based on nano-SiO2 synergistic surfactant

Xiaona Yang, Peng Xiao, Yu Shi, Bo Zhao, Xiaoxiao Liu, Xiaosheng Huang and Zixi Chen

Energy, 2025, vol. 330, issue C

Abstract: To clarify the effects of nano-SiO2 synergistic surfactant (cetyltrimethyl ammonium bromide, CTAB) on coal wettability and CH4 adsorption/desorption and diffusion, different systems of coal-nanoparticles-surfactant composite models were constructed using molecular simulation in Materials Studio. Detailed investigations were conducted on equilibrium adsorption configuration, interaction energy, CH4 adsorption configuration and adsorption amount, diffusion coefficient and relative concentration distribution, revealing the mechanism by which the nano-SiO2 synergistic surfactant enhances coal wettability and promotes gas desorption. The results indicate that the CTAB-modified nano-SiO2 to promotes the binding and adsorption of coal and water, altering its wettability. The interaction energy of system 1 and system 2 are −3.709 kcal/mol and −3.187 kcal/mol, respectively, demonstrating that CTAB-modified nano-SiO2 weakens the interaction between coal and water adsorbed with CTAB. The aggregation of CTAB-modified nano-SiO2 within the coal is pronounced, occupying the CH4 adsorption site, thereby reducing CH4 adsorption. In system 4 and system 5, the gas diffusion is affected by CTAB, nano-SiO2 and pressure, which restricts the free movement of CH4 within the slit pores. When the relative concentration of CH4 increases due to CTAB-modified nano-SiO2, the CH4 diffusion is hindered and weakened.

Keywords: Nano-SiO2; Surfactant; Adsorption; Diffusion; Wettability; Molecular simulation (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544225026416
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:330:y:2025:i:c:s0360544225026416

DOI: 10.1016/j.energy.2025.136999

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().