Optimization of acid modifier and its effect on the wettability of anthracite coal.

This research aimed to investigate the influence of free radicals on the wettability of Guizhou anthracite coal. The best acid modifier was selected through quantum chemistry and sedimentation experiments. Infrared spectroscopy (FTIR), paramagnetic resonance spectroscopy (EPR), and wetting heat experiments were carried out to investigate the effect of acid modifiers on the wetting properties of coal. The results of the study show that, among the three modifiers tested (APG, AEO3, and NP-10), alkyl glycoside (APG) exhibited the best wetting performance and strongest reactivity with the coal molecules. The best wetting effect was achieved with 1% APG + 6% HF. The acid modifier increased the concentration of hydrophilic functional groups and free radicals. Under the action of the acid modifier, the hydrophobic functional groups in the coal samples break off to form active sites (free radicals) and then continue to be converted into hydrophilic functional groups, which in turn improves the wettability of the coal samples. The measured wetting heat of the post-modified experimental coal sample increased by 14.86%, which proved that the acid modifier could improve the wettability of the coal. This study provides theoretical insights into the quantum chemical optimization of modifiers, gas disaster prevention, and dust management of anthracite coal.