The synthesis, performance, and functional mechanism of an eco-friendly suppressant derived from hydroxyethyl cellulose for the mitigation of coal dust pollution

Abstract

To address fugitive dust pollution during coal transportation and stockpiling, this study develops an efficient and environmentally friendly polymer consolidating agent, HEC-AM-IA, through the synthetic modification of hydroxyethyl cellulose (HEC). Fourier-transform infrared spectroscopy confirms the successful grafting of functional groups, while thermal analysis reveals excellent stability. Scanning electron microscopy-energy dispersive spectroscopy reveals a dense crosslinked structure crucial for dust suppression. The uniaxial compressive strength of coal treated with HEC-AM-IA is 2.8 times that of unmodified HEC, demonstrating enhanced bonding and cohesion. HEC-AM-IA also exhibits superior wettability, with a lower contact angle, enabling faster spreading and deeper infiltration into the coal matrix, as well as strong water retention that delays evaporation and maintains film integrity. Molecular dynamics simulations corroborate the enhanced wetting with larger contact areas and stronger interfacial interactions. Mechanistically, modification increases the electrostatic potential differences and uneven charge distribution, whereas polar groups enhance hydrogen bonding, adsorption on coal, and water molecule activity. Frontier orbital analysis indicates higher molecular reactivity, supporting stable interfacial interactions that improve spreading, coverage, and binding. Wind erosion tests verify that HEC-AM-IA forms coal crusts with superior integrity and stability under high winds, showing significantly less mass loss than water or HEC.