Surface Chemical Aspects of Coagulation, Deposition, and Filtration Processes: Variation of Electrokinetic Potential at Metal Oxide-Water and Organic-Water Interfaces in the $Na^+$ and $Ca^{2+}$ Ion Solutions

  • Kim, Sung-Jae (Department of Marine Environmental Engineering Institute of Marine Industry College of Marine Science Gyongsang National University)
  • Published : 2000.09.01

Abstract

This study measured the zeta potential of both latex colloidal particles with carboxylate surface groups and glass beads (collectors) with silanol surface group employing various solution with different chemical characteristics. The results have been compared with the surface chemistry theory. The zeta potential of the particle and collector increased with increasing pH up to 5.0 regardless of the solution chemistry. For a monovalent electrolyte solution(sodium chloride solution) the zeta potential steadily increased until the pH reached 9.5. In contrast, little change in zeta potential was made between 5.0 and 9.5 for a divalent electrolyte solution (sodium chloride solution) the zeta potential steadily increased until the pH reached 9.5. In contrast, little change in zeta potential was made between 5.0 and 9.5 for a divalent electrolyte solution (calcium chloride solution). In other words, the more the pH decreases, the larger the effect of neutral salts, such as NaCl and CaCl$_2$, have on the ζ-potential values. In this study, the PZPC(point of zero proton condition) of the particle and collector occurred below a pH of 3.1, H(sup)+ and OH(sup)- acted as a PDI (potential determining ion), and Na(sup)+ acted as an IDI(indifferent ion). The magnitude of the negative ζ-potential values of the particle and collector monotonically increased as the concentrations of Na(sup)+ or Ca(sup)2+([Na(sup)+] or [Ca(sup)2+]) decreased (the values of pNa or pCa increased). In the case of latex particles, the ζ-potential should aproach zero (isoelectric point; IEP) asymptotically as the pNa approaches zero, while in the case of calcium chloride electrolyte, ζ-potential reversal may be expected to occur around 3.16$\times$10(sup)-2MCaCl$_2$(pCa=1.5). pH, valance and ionic strength can be used in various ways to improve the water treatment efficiency by modifying the charge characteristics of the particle and collector. Predictive capability is far less certain when EDL(electrical double layer) repulsive forces exist between the particle and collector.

Keywords

References

  1. Journal of Colloid and Interface Science v.31 Stability of Colloidal Silica : Ⅰ. Effect of Simple Electrolytes Allen, L. H.;Matijevic, E.
  2. Journal American Water Works Association v.82 Surface Chemistry in Water Treatment : Reactions at the Solid-Liquid Interface Bales, R. C.
  3. Report AC-8-84, W.M.Keck Laboratory, California Institute of Technology Surface Chemical and Physical Behavior of Chrysotile Asbestos in Natural Waters and Water Treatment Bales, R. C.
  4. Geochim. Cosmochim. Acta. v.45 Adsorption of Natural Organic Matter at the Oxide/Water Interface Davis, J. A.
  5. The Geochemistry of Natural Waters Drever, J. I.
  6. Journal of Hydraulic Engineering v.113 Adsorption of Inorganic Pollutants in Aquatic Systems Dzombak, D. A.;Morel, F. M. M.
  7. Ph. D. dissertation, Harvard University Mechanisms of Particle Capture in Water Filtration FitzPatrick, J. A.
  8. Transactions of the American Institute of Mining, Metallurgical, and Petroleum Engineers v.202 Quartz Flotation with Anionic Collectors Gaudin, A. M.;Fuerstenau, D. W.
  9. Ph. D. dissertation, University of London Molecular Forces and Electrokinetic Effects in Filtration Gregory, J.
  10. Particulates in Water, Advances in Chemsitry Series v.189 Characterization of Surface Chemical Properties of Oxides in Nautral Waters : The Role of Specific Adsorption in Determining the Surface Charge Hohl, H.;Sigg, L.;Stumm, W.;M. C. Kavanaugh(ed.);J. O. Leckie(ed.)
  11. Nature v.282 The Surface Charges of Suspended Particles in Estuarine and Coastal Waters Hunter, K. A.;Liss, P. S.
  12. Zeta Potential in Colloid Science : Principles and Applications Hunter, R. J.
  13. The Chemistry of Silica Iler, R. K.
  14. Journal of Colloid and Interface Science v.40 Computer Simulation of the Conductometric and Potentiometric Titrations of the Surface Groups on Ionizable Latexes James, R. O.;Davis, J. A.;Leckie, J. O.
  15. Surface and Colloid Science v.12 Characterization of Aqueous Colloids by Their Electrical Double-Layer and Intrinsic Surface Chemical Properties James, R. O.;Parks, G. A.;Matijevic, E.(ed.)
  16. Journal of Colloid and Interface Science v.49 The Electrokinetic Potential of Glasses in Aqueous Electrolyte Solutions Jednacak, J.;Pravdic
  17. Ph.D. Dissertation, Auburn University Factors Influencing Colloidal Particle Transport in Porous Media Kim, S. J.
  18. Journal of the Chemical Society, Faraday Transactions Ⅱ v.75 Particle Adhesion and Removal in Model Systems.-Part 1. Monodispersed Chromium Hydroxide on Glass Kowlakowski, J. A.;Matijevic, E.
  19. Colloidal Dispersions Fundamentals of Electrical Double Layers in Colloidal Systems Lyklema, J.;J. W. Goodwin(ed.)
  20. Surface Science v.5 Electrokinetic and Adsorption Studies on Quartz Li, H. C.;De Bruyn, P. L.
  21. Water Resources Research v.22 Particle Transport Through Porous Media McDowell-Boyer, L. M.;James, R. H.;Sitar, N.
  22. Chemical Reviews v.65 The Isoelectric Points of Solid Oxides, Solid Hydroxides and Aqueous Hydroxo Complex Systems Parks, G. A.
  23. Advances in Chemical Series v.67 Aqueous Surface Chemistry of Oxides and Complex Oxide Minerals Parks, G. A.
  24. Journal of colloid and Interface Science v.55 Ligand Properties of Surface Silanol Groups: Surface Complex Formation with $Fe^{3+}$, $Cu^{2+}$, $Cd^{2+}$, and $Pb^{2+}$ Schindler, P. W.;Frst, B.;Dick, R.;Wolf, P. U.
  25. Journal of Environmental Science and Technology v.11 Chemical Interaction in Partical Separation Stumm, W.
  26. Aquatic Chemistry(2nd ed.) Stumm, W.;Morgan, J. J.
  27. Electroanalytical Chemistry and Interfacial Electrochemistry v.22 The Electrical Double Layer on Silica in the Presence of Bivalent Counter-ions Tadros, Th. F.;Lyklema, J.
  28. Ph.D. Dissertation, Johns Hopkins University Physicochemical Aspects of Particle Deposition in Porous Media Tobiason, J. E.