Electrokinetic measurements by electroacoustical methods

• Published in: Advances in colloid and interface science 1989, Vol.30 (1-2), p.111-151
• Main Authors: Babchin, A.J., Chow, R.S., Sawatzky, R.P.
• Format: Article
• Language: English
• Subjects: Chemistry; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; Physical and chemical studies. Granulometry. Electrokinetic phenomena
• ISSN: 0001-8686; 1873-3727
• DOI: 10.1016/0001-8686(89)80005-3

A new electroacoustic technique for the application of electrokinetic measurements is considered from theoretical, experimental, and applied points of view. Chapter II reviews the physical principles of the electroacoustical measurements. The two modes of measurements that are possible, ultrasound vibration potential (UVP) and electrokinetic sonic amplitude (ESA), are described and their relation to electrophoretic mobility using alternating electric fields is demonstrated. The contents of Chapter III include a fluid mechanical overview of the oscillation of a spherical colloid particle under the influence of a sound wave that is propagating through the colloidal system. Electrophoretic mobility using alternating electric fields, including an expression for the high frequency electrophoretic mobility is considered in Chapter IV. The derived expression for the high frequency mobility takes into account inertia effects in full and demonstrates the sensitivity of electroacoustical methods not only to the zeta potential of the colloid particles, but also to coagulation/coalescence processes. Along with the review of some experiments, which prove the consistency between the electroacoustical and classical electrophoretic measurements, new experimental results are presented in Chapters V and VI for the application to oil-in-water and water-in-oil emulsions. The main advantages of the new electroacoustical technique are its capability of providing electrokinetic data in nontransparent and nonpolar media along with its ability to monitor coagulation/coalescence processes.