Electroacoustic Measurement of Zeta Potential in Aqueous Colloids

Abstract

An electroacoustic probe was developed for measuring acoustic impedance and Zeta potential in colloids simultaneously. Meanwhile, a set of experimental device was established and its stability verified to be good after repeated experiments. Measured acoustic impedance by multiple echo method was incorporated into a theoretical model to calculate Zeta potential. The measurements of Zeta potential in the colloids of nano-loess and nano-titanium dioxide were -52.69 and -16.09 mV, respectively. Zeta potential trend of 5%～30% volume concentration colloids of silica sol was measured and analyzed, showing that the method can be used for high concentration plastic body measurement. The comparison with the results of Malvern Zeta potential measurement instrument yielded a small and accepted deviation. This method is expected to achieve on-line measurement.