NONEQUILIBRIUM ELECTROKINETIC PROPERTIES OF MAGNESITE AND DOLOMITE DETERMINED BY THE LASER-DOPPLER ELECTROPHORETIC LIGHT-SCATTERING (ELS) TECHNIQUE - A SOLIDS CONCENTRATION-EFFECT

Zeta potential histograms of finely ground magnesite and dolomite susp ended in water, determined by the laser-Doppler electrophoretic light scattering technique, have been found to be modified by increasing the solids concentration from 100 to 5000mg l(-1). The zeta potential pea k was continuously shifted from -20 to +15mV with a reversal at a soli ds content of 2000mg l(-1) for magnesite and 800mg l(-1) for dolomite. For magnesite, this effect seems to be less pronounced, but for dolom ite it resembles the pattern for calcite published in the literature.