Comparison of surface energy and adhesion energy of surface-treated particles

The mineral industry uses tremendous amounts of water every year in the processing ores. Sustainable practices associated with ores are, therefore, critical importance. project described herein is first step toward producing a dry, particle-separation process based upon control and exploitation adhesive forces. In this research, goal to determine surface energy particles, further, whether solid can be used understand adhesion between these particles surface-modified substrates. Glass spheres were chosen represent silicate minerals, most abundant type minerals found deposits. was by using contact angle measurements applying van Oss-Good-Chaudhury (VOGC) method. VOGC method utilizes three-liquid triads Lifshitz-van der Waals, Lewis acid base components. Surface energies from plasma-cleaned glass 40.2 60.2 mJ/m2; for same hydrophobic chemical treatment, trichloro(octadecyl)silane (TCOD), 20.8 20.9 hydrophilic treatment (n1-(3-trimethoxysilylpropyl) diethylenetriamine (TMPA)) 46.3 61.6 mJ/m2. particle-substrate also measured mechanical impact tester. disks beads used, cleaned treated TCOD TMPA. A custom horizontal tester designed measure force disk substrate. Impact disk/particle puck causes particle removal as tensile forces act on particles. detachment are equal at size. Johnson-Kendall-Roberts (JKR) theory interfacial surface. average plasma glass, TMPA 44.8 mJ/m2, 21.6 40.1 respectively. These values good agreement literature determined above, demonstrating that two approaches compare favorably, despite dramatically different methods (molecular vs mechanical) utilized.