Electrostatic Properties in Non-aqueous Media

The role of electrostatic repulsion in the stability of suspensions of particles in non-aqueous media is not yet clear. In order to attempt to apply theories such as the DLVO theory (to be introduced in Section 5.2) one must know the electrical potential at the surface, the Hamaker constant, and the ionic strength to be used for the non-aqueous medium these are difficult to estimate. The ionic strength will be low so the electric double layer will be thick, the electric potential will vary slowly with separation distance, and so will the net electric potential as the double layers overlap. For this reason the repulsion between particles can be expected to be weak. A summary of work on the applicability or lack of applicability of DLVO theory to non-aqueous media has been given by Morrison [268], 

and Schramm, L.L. (1989) Fuel Process. Technol, 23, 215-231. Hunter, R.J. (1981) Zeta Potential in Colloid Science, Academic Press, New York. 

Masliyah, J.H. (1994) Electrokinetic Transport Phenomena, Alberta Oil Sands Technology and Research Authority, Edmonton. 

Isaacs, E.E. and Chow, R.S. (1992) in Emulsions, Fundamentals and Applications in die Petroleum Industry (ed. L.L. Schramm), American Chemical Society, Washington, DC, pp. 51 -77. 

Hunter, R.J. (1993) Introduction to Modem Colloid Science, Oxford University Press, Oxford. 

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