Surface Modification of Particles in Fluidised Beds at Atmospheric Conditions

In this study, a method to uniformly functionalize the surface of particles using self-limiting vapor-phase deposition of silanes is presented. The deposition process is carried out at atmospheric pressure in a fluidized bed reactor and the correlation between surface energy and the electrostatic properties of the resulting particulate materials was studied. Glass beads were functionalized with a fluorine-containing silane to change their cohesion properties and therefore inter-particle forces. This demonstrates the potential use of fluidized beds as an alternative route to wet processes producing less wastes with a solvent-free process and achieving more selectivity with shorter processing times. Characterization techniques such as SEM, XPS, TGA, Surface energy and Free energy analysis as well as a method for assessing the electrostatic properties and the polarity of charged glass beads used in this study.