ZETA POTENTIAL IN POROUS MATERIAL

Electroacoustics offers unique possibility of characterizing both types of heterogeneous systems: porous material and particulates with the same device. Model DT-330 is such Universal Zeta potential Probe, whereas Model DT-350 was designed for porous materials exclusively. Similar measurement can be conducted with the Model DT-1202 if it is equipped with Option OP0014.

The main principles of Electroacoustics in porous material are presented in ISO Standard 13099, Parts 1 and 3: 2012. Colloidal systems – Methods for Zeta potential determination.

All details of these instruments are described in the US Patent by Dukhin, Goetz and Thommes from 2012 “Method for determining porosity, pore size and zeta potential of porous bodies”.

Zeta potential probe designed by Dispersion Technology Inc has a flat face. Therefore it can be simply placed on the top of the porous body, as shown below with a sandstone core.

Then we can change pH of the liquid that saturates porous material and observe how surface charge of the pores varies with pH. Such pH titration of Berea SS sandstone core is shown below.

Some examples of these measurements can be found in the following papers:

• • Dukhin, A.S., Swasey, S. and Thommes M. “A method for pore size and porosity analysis of porous materials using electroacoustics and high frequency conductivity“, Colloids and Surfaces, 437, pp. 127-132 (2013)

  • Dukhin, A.S., Goetz, P.J., and Thommes M. “Seismoelectric effect.: A non-isochoric streaming current. 1. Experiment“, J. Colloid and Interface Science, 345, p.547-553 (2010)

  • Dukhin, A.S. and Shilov, V.N. “Seismoelectric effect.: A non-isochoric streaming current. 2. Theory“, J. Colloid and Interface Science, 346, p.248-253 (2010)

  • Dukhin, A.S. and Parlia, S. “ Studying homogeneity and zeta potential of membranes using electroacoustics “, J. of Membrane Science, vol. 415-415, pp. 587-595 (2012)