Review of the measurement of zeta potentials in concentrated aqueous suspensions using electroacoustics.

This paper reviews the technique of electroacoustics as it has been applied to aqueous suspensions of inorganic particles. It starts by charting the development of the technique from its earliest beginnings in the 1930s to the present day. The technique has become well established in the last decade with the advent of the Acoustosizer and the Acoustosizer II. Illustrations of how the technique can be used are given based on the author's own experience, especially the measurement of iso electric points, the adsorption of polyelectrolytes, the effect of ionic strength, the effect of powder surface area and the dissolution of material from powders. Some new data on (a) the adsorption of different molecular weights of polyacrylic acid onto alumina and (b) titanium dioxide suspensions are also presented.