Experimental and molecular dynamics simulation study of the effect of composite surfactants on wetting of coal dust

To improve surfactant wetting action on coal dust in the process of mine spray dust reduction, this paper adopts a combination of experiments and molecular simulation to study the wetting properties and mechanism of different kinds of active agents on coal dust and selects the compounded surfactants with better dust reduction effect. The results show that: fatty alcohol polyoxyethylene ether can reduce the surface tension to 34.16 mN center dot m- 1, which is 35.84 mN center dot m- 1 comparatively less than that of pure water; dodecylphenol polyoxyethylene ether and poly(ethylene glycol) octyl phenyl ether have the maximum electrostatic potentials of 0.0892 a.u and 0.0908 a.u, which exceed that of water molecules, which indicate that the nonionic active agents are the most polar, and it is easy for them to form the hydrogen bonding with water, and the ability to reduce surface tension is superior to other types of active agents; molecular simulation results show that the non + anionic complex system can form a tighter adsorption layer between coal and water, so that the water molecules move more vigorously, moving from the molecules of water to those of coal, thus producing a better wetting effect than the monomer active agent. In addition, dust settling experiments and particle size experiments were conducted to verify the reasonableness of the microscopic simulation. The study's findings can provide a reference for identifying and designing compounded surfactants with excellent wetting performance to improve the dust reduction effect.