caa a22 4500 605489319 CHVBK 20210128100459.0 cr unu---uuuuu 210128e20151101xx s 000 0 eng 10.1134/S1061933X15060046 doi (NATIONALLICENCE)springer-10.1134/S1061933X15060046 Electrosurface properties of kaolin and bentonite particles in solutions of electrolytes and surfactants [Elektronische Daten] [S. Barany, R. Meszaros, R. Taubaeva, K. Musabekov] The influence of pH and KCl, CaCl2, AlCl3, sodium dodecyl sulfate, and cetyltrimethylammonium bromide (CTAB) concentrations on electrokinetic potential ζ of particles and the electrical conductivity of aqueous kaolin and bentonite suspensions has been studied. At "natural” pH values of the suspensions (7.2-7.4), the ζ potential of bentonite is much higher (-45 mV) than that of kaolin (-20 mV), and this difference takes place in a wide pH range (2-11). In both cases, a rise in pH leads to an increase in the absolute values of ζ due to the enhanced dissociation of surface OH groups. Charge reversal is observed at pH of approximately 2 and pH 2.5 for kaolin and bentonite, respectively. The dependence of the ζ potential of the particles on KCl concentration passes through a maximum, while the addition of CaCl2 and AlCl3 causes a substantial reduction in ζ and particle charge reversal, respectively. An increase in CTAB concentration C in a suspension leads to a decrease in the negative ζ values followed by particle charge reversal, with the ζ(C) curve tending to reach a plateau. It has been shown that the initial regions of the dependences of the relative electrical conductivities of the suspensions on the volume fraction of the solid phase are almost linear, with their slopes decreasing with a rise in electrolyte concentration. Hence, the contribution of the surface conductivity to the total suspension conductivity decreases with a rise in the ionic strength of a solution. The values of the electrokinetic charge calculated from the data on the ζ potential, i.e., the charge of the slipping plane, have appeared to be one to two orders of magnitude lower than the surface charges of the minerals. This finding suggests that counterions are predominantly located in the hydrodynamically motionless part of the electrical double layer. Pleiades Publishing, Ltd., 2015 Barany S. Institute of Chemistry, University of Miskolc, 3515, Miskolc-Egyetemvaros, Hungary aut Meszaros R. Institute of Chemistry, University of Miskolc, 3515, Miskolc-Egyetemvaros, Hungary aut Taubaeva R. Taraz State Pedagogical Institute, Tole be street 62, Taraz, Kazakhstan aut Musabekov K. Al-Farabi Kazakh State University, pr. Al-Farabi 71, 050040, Almaty, Kazakhstan aut Colloid Journal Pleiades Publishing 77/6(2015-11-01), 692-697 1061-933X 77:6<692 2015 77 10595 https://doi.org/10.1134/S1061933X15060046 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1134/S1061933X15060046 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Barany S. Institute of Chemistry, University of Miskolc, 3515, Miskolc-Egyetemvaros, Hungary aut NATIONALLICENCE 700 1- Meszaros R. Institute of Chemistry, University of Miskolc, 3515, Miskolc-Egyetemvaros, Hungary aut NATIONALLICENCE 700 1- Taubaeva R. Taraz State Pedagogical Institute, Tole be street 62, Taraz, Kazakhstan aut NATIONALLICENCE 700 1- Musabekov K. Al-Farabi Kazakh State University, pr. Al-Farabi 71, 050040, Almaty, Kazakhstan aut NATIONALLICENCE 773 0- Colloid Journal Pleiades Publishing 77/6(2015-11-01), 692-697 1061-933X 77:6<692 2015 77 10595