[This article belongs to Volume - 54, Issue - 09]
Gongcheng Kexue Yu Jishu/Advanced Engineering Science
Journal ID : AES-13-11-2022-403

Title : Influence Mechanism of Nonionic Surfactant on Coal Wettability Based on Molecular Dynamics Simulation
ZHANG Jianguo, LIU Yiting, WANG Man, WANG Yingwei, LI Hongmei, XIE Jing, ZHAO Yun, ZHOU Weiqi, YE Siqi,LI Luming, QI Rui,

Abstract :

The coal dust disaster is serious in deep mining of coal mine. The use of nonionic surfactant can effectively improve the wettability of coal dust and inhibit the generation and diffusion of coal dust. In order to explore the wetting process and mechanism of different surfactants on coal dust surface, the effects of nonionic surfactants lauryl glucoside (APG) and Triton X–100 on the wettability of coal dust surface were studied by molecular dynamics simulation and experiment. Three coal–water interface adsorption system models were established based on benzene ring carbon skeleton structure. Analysis the adsorption equilibrium configurations and spatial distribution of the surfactant on surface of coal were calculated on the basis of the interaction energy between coal/surfactant/water and energy changes, looked at the two kinds of surfactants and the ability of water molecules to form hydrogen bond. The coal samples from three groups of coal seams in Pingdingshan mining area in Henan Province were tested, the experiments of sedimentation and contact angle were carried out, and the surface free energy composition of the coal samples was calculated. The simulation results were verified, the characteristics of aromatic hydrocarbon groups in the coal samples and the interaction mechanism between Triton X–100 and coal molecules were tested by Fourier infrared spectroscopy (FT–IR). The results showed that when the adsorption equilibrium state is reached, the non-ionic surfactant molecules are connected with each other through alkyl chains to form an aggregation state, which is distributed at the coal water interface and the water gas interface. Triton X–100 can promote the adsorption of water molecules on the coal surface by enhancing the interaction with water molecules, which has a great impact on the wettability of the coal surface. The indoor test results showed that the wetting effect of Triton X–100 on the coal surface is better than APG, and the effect is the best at the critical micelle concentration. The higher the content of aromatic hydrocarbons in coal dust, the better the adsorption of Triton X–100. The research results provided a theoretical support and guidance for scientific and efficient dust suppression in deep mining