To address the problem of the high viscosity of current composite dust suppressants, which results in spray droplet sizes that are not optimal for capturing respirable dust, a low viscosity, proactive coal-adhesive, long-lasting spray dust suppressant, XG-AOS/Tre, has been developed. The suppressant utilizes xanthan gum (XG) from microbial fermentation, with α-olefin sulfonate grafted onto its hydroxyl groups to form a copolymer (XG-AOS), reducing its viscosity while maintaining the surface activity of the hydrocarbon chain and its affinity for coal dust. It has a weighted average molecular weight of 398341, a surface tension of 26.1 mN/m, a viscosity of 1.59 mPa·s, and a contact angle of 48° with coal cake. The suppressant achieves a total dust suppression rate of 85.7 % and a respirable dust suppression rate of 85.9 %. Because of its surface activity and high molecular weight, it efficiently wets and settles coal dust. It retains 47.3 % of the water in its solution 24 h after being sprayed and forms an adhesive film upon complete evaporation, providing the coal dust with resistance to wind erosion. The dust suppressant improves the dust suppression rate for dust control in coal mining. Its properties contribute to the sustainable development and environmental protection of the coal industry.
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