| In order to further analyze the wetting performance and mechanism of sodium dodecyl benzene sulfonate (SDBS) on coking coal, the wetting characteristics of clear water, 0.005%, 0.05% and 0.5% SDBS solutions were determined by contact angle and reverse osmosis tests with Huainan coking coal, and then use Materials Studio molecular simulation software establishing the water-coal and water-surfactant-Coal models to investigate the wetting process of SDBS on the coal surface. The results show that SDBS solution can significantly improve the wetting property of clear water, and the contact angle of 0.5% SDBS solution is the smallest, 16.52°, and the amount of moisture absorption is the largest, 261mg, with the most obvious wetting effect; the simulation results show that the adsorption configuration of the hydrophobic tail chain adsorption of SDBS molecules on the surface of coal, hydrophilic headgroups towards the water can reduce the interfacial tension between water and coal. The addition of surfactant SDBS decreased the intermolecular non-bonding energy, and the larger the mass fraction of SDBS, the stronger the intermolecular adsorption. With the increase of SDBS mass fraction, the contact surface between SDBS and coal is larger, the spatial distribution range of alkyl chains is wider, and the Mean Square Displacement (MSD) and diffusion coefficient of water molecules increase, so that the wetting effect of coal is stronger. |
