Dependence of the water wettability of the surfaces of fossil coals on their structure and properties

Abstract

The dependence of the water wettability of coal surface on the structure and properties of coals of different stages of diagenesis and metamorphism was studied based on the evaluation of the angles of contact. It was found that the caking coals of Zh and K ranks exhibited maximum hydrophobic properties. Hydrophilic properties were most pronounced in brown coals and low-rank black coals with the highest concentrations of hydroxyl and carboxyl groups and a developed porous structure.