Article ID Journal Published Year Pages File Type
238311 Powder Technology 2009 5 Pages PDF
Abstract

The dispersion of powders in liquids is an operation used in many industries, which depends on parameters involving both the process (stirring power, temperature and reactor geometry) and the material (the powder, the liquid and the powder/liquid interface). Even though dispersion operations have been the object of several investigations, the importance of the various parameters and especially the physicochemical properties is rarely treated. This paper presents an experimental study of the kinetics of talc dispersion in water based on prior determination of powder properties (particle size, density, surface area and surface free energy), which are used to calculate the different work functions involved in dispersion (adhesion, immersion and spreading). Experiments are presented using an optical fibre sensor to determine the dispersion kinetics of talc in water as a function of stirring power and powder concentration. These results are found to correlate with the energy calculated to be required to cross the liquid–gas interface.

Graphical abstractThis paper presents a study of the kinetics of talc dispersion in water. The results show a relation between the optimal power agitation and the total work of dispersion calculated from the surface tension of the water, the dynamic contact angle between the talc and the water and the total surface of the particles.Figure optionsDownload full-size imageDownload as PowerPoint slide

Related Topics
Physical Sciences and Engineering Chemical Engineering Chemical Engineering (General)
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