Synergistic oxidative modification and covalent cross-linking for the construction of sesbania gum-based high efficiency dust suppression foam sols.

To effectively utilize sesbania gum in coal dust control and address the limitations of excessive viscosity and mediocre strength, oxidation treatment was used to improve its fluidity. Polyvinyl alcohol (PVA) and sodium trimetaphosphite (STMP) were used to enhance oxidized sesbania gum OSG, and crosslinking technology was used to improve its mechanical stability. This study developed a novel foam dust suppressant OSG-PVA/SDBS by response surface design, and the optimized dust suppressant material exhibited excellent adhesion and curing properties. It was found that sulfonic acid groups (-SOH) of SDBS gradually congregate to occupy the binding site on the OSG-PVA polymer chain, bolstering the water-locking capacity of the liquid film and the foam stability. Concurrently, the hydrophobic tail chains in SDBS adsorb onto the hydrophobic points on the coal surface, establishing a dual adsorption mechanism. Simulation revealed that the thickness of water molecule absorption layer increased by 11.3 Å under this dual adsorption, strengthening the interaction between coal and water. After repeated wind erosion and rain washing, the coal samples sprayed with OSG-PVA/SDBS exhibited low wind erosion rate (22.64 %) and rain erosion rate (23.22 %). Moreover, the dust suppression rate surpassed 95 % following outdoor application of the suppressant foam. These results offer innovative perspectives and strategies for the research and mitigation of coal dust pollution.