Wetting of powdered coals by alkanol-water solutions and other liquids

Molecular Model of Xishan Bituminous Coal Surface and Its Wetting Properties

“…This may explain why the computed heat of wetting of coal in methanol is smaller than the measured one. Unlike methanol, which is a good medium to wet coal, 31 water can reach only a portion of the coal pores in the wetting experiment. 34 However, in the present simulation, the coal model surface was completely exposed to water molecules, which cannot be achieved in the calorimetric experiment.…”

“…It can be found that the heat evolutions in water and in methanol are 0.021 and 0.069 J/m 2 , respectively. In general, hydrophobic coals are characterized by a higher heat value for immersion in methanol than in water. , Thus, this coal surface model should be classified as a predominantly hydrophobic one because the exothermic heat in water is remarkably lower than that in methanol. This is consistent with its properties of high rank bituminous coal …”

Characterization of the Wetting and Dewetting Behavior of Powders

“…Also there are differences in the manner in which time of wetting was measured. Some investigators have determined the time for the last trace of powder to be wetted 32,36) whereas others have determined the time for the vast majority of the particles to sink 34) . The sink time method has been used by investigators to measure the wettability of a wide variety of solids: organic chromium pigment 37,38) flour sulfur and molybdenite 39) .…”

Flotation and flocculation chemistry of coal and oxidized coals

“…Glanville and Wightman [52] have shown that the heats of immersion of pow- It is clear from the published literature that heat of wetting studies can be used to characterize surfaces and provide a potential approach to the study of coal surface heterogeneity. 26 3.4…”