The effect of microemulsion on coal wetting characteristics and physicochemical structure

Abstract To study the effect of microemulsion on the wettability and physicochemical structure of coal, various experiments (contact angle, Fourier infrared spectroscopy, scanning electron microscope) were conducted to study the mechanism of physicochemical structure on wettability. The results show that the microemulsion exhibited stronger wetting properties than traditional wetting agents such as water and sodium lauryl sulfate solution (SDS). The contact angles of the three-phase microemulsions were relatively small, among which the W/O type had better wettability. The increase in area percentage of benzene ring with one adjacent H, CH structure, OH…N structure had a tendency to inhibit coal wetting while the increase in area percentage of benzene ring with three adjacent H, CH3 structure, OH…π structure exhibited a tendency to promote coal wetting. Microemulsion could significantly increase the wettable area of coal. The research results have important practical significance for the configuration of mining wetting agents, reducing coal dust pollution, and diminishing coal mine disasters.