Characterization of the Wetting and Dewetting Behavior of Powders

Abstract

Abstract

Depressing effect of flocculants on molybdenite flotation

“…At pH 4, the contact angle was determined to be about 150°, in alkaline solutions it decreased to 100°, and so these measurements turned out to be much more sensitive to pH (to electrical charge at solid/liquid interface). In the further analysis of these data, Chander et al (2007) showed an excellent correlation between molybdenite oil flotation recovery and oil/water contact angle of molybdenite ( Fig. 6) (in oil flotation an oil phase is substituted for the gaseous phase).…”

“…Also plotted is the effect of pH on the oil/water contact angle of molybdenite, expressed in terms of the flotation dewetting relation ð1 À cos hÞ(Chander et al, 2007).…”

Plasma polymerization of sulfur-rich and water-stable coatings on silica particles

“…The water adsorption tests and water contact angle (WCA) evaluations of uncoated and PPT-coated silica particles were carried out according to the Washburn capillary rise method [40]. A dynamic contact angle meter (DCAT21, Dataphysics) equipped with a Wilhelmy balance controlled by SCAT software was utilized.…”

“…Prior to each measurement, the cell was ultrasonicated in acetone and hexane and rinsed with Milli-Q water followed by drying at 100°C for 1 h. The packed cell with 4 g of particles was placed in close contact with water, and the mass of water adsorbed into the bed of particles was recorded as a function of time. Weight square (m 2 ) values of adsorbed water versus time (t) were plotted and utilized to calculate the WCA of particles according to the Washburn equation [40]:…”

“…The capillary constant (C), which is mainly dependent on the porous architecture of the packed bed, was determined using n-Hexane as a probe liquid providing a contact angle of 0° [40,41].…”