Influence of solution pH on stability of aluminum oxide suspension in presence of polyacrylic acid
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The effect of solution pH and molecular weight of polyacrylic acid (PAA) on its adsorption as well as on stabilization-floculation properties of the colloidal Al2O3 and electrolyte solution systems was studied.
The measurements showed that at pH = 6, the presence of the polymer of molecular weight 2 000 and 240 000 does not change stability of Al2O3 suspension. However at pH =3 and 9 the effect of polyacrylic acid is significant. At pH = 3 it creates destabilization of the suspension while at pH = 9 PAA it improves significantly the stability of Al2O3.
It was shown that the increase in solution pH affects conformation of adsorbed macromolecules which causes the decrease in PAA adsorbed amount and thickness of polymer adsorption layer.
By comparing the values of diffusion layer and surface charges, main effects responsible for the decrease in surface charge and ζ potential of the solid in the presence of the polymer as well as suspension stability were determined.
KeywordsPolymer adsorption pH influence Polyacrylic acid Suspension stability Alumina
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- Crummett, W.B., Hummel, R.A.: The determination of tracers of polyacrylamides in water. J. Am. Water Works Assoc. 55, 209–219 (1963) Google Scholar
- Drzymała, J., Fuerstenau, D.W.: Adsorption of polyacrylamide, partially hydrolyzed polyacrylamide and polyacrylic acid ferric oxide and silica, process technol. In: Proc., Flocculation in Biotechnology and Separation Science, pp. 45–60 (1987) Google Scholar
- Fleer, G.J., Cohen Stuart, M.A., Scheutjens, J.M.H.M., Cosgrove, T., Vincent, B.: Polymers at Interaces. Chapman & Hall, London (1993) Google Scholar
- Grządka, E., Chibowski, S.: Influence of a kind of electrolyte and its ionic strength on the adsorption and zeta potential of the system PPA/MnO2/electrolyte solution. Physicochem. Probl. Mineral Process. 43, 31–42 (2009) Google Scholar
- Markovic, B.: Adsorption of polyacrilic acid on alumina and silicor carbide. Doctoral Thesis, University of Zagreb, Croatia (1996) Google Scholar
- Napper, D.H.: Polymeric Stabilization of Colloidal Dispersions. Academic Press, New York (1983) Google Scholar
- Pigoń, K., Ruziewicz, Z.: Physical Chemistry. PWN, Warszawa (1980) Google Scholar
- Wiśniewska, M.: Comparative studies of adsorption mechanism and conformation of nonionic polyethylene glycol (PEG) and anionic polyacrylic acid (PAA) macromolecules on the Al2O3 surface; the temperature influence. Ann. UMCS Sect. AA Chem. LXII, 181–193 (2007a) Google Scholar
- Wiśniewska, M.: The temperature influence on the electrokinetical properties of Al2O3 polyacrylic acid solution interface. In: Wilk, K. (ed.) Surfactants and Dispersed Systems in Theory and Practice, pp. 311–314. PALMAPress, Wroclaw (2007b), ISBN 83-7076-125-9 Google Scholar
- Wiśniewska, M.: Temperature dependence of polyacrylic acid adsorption on the alumina surface; free energy of polymer adsorption. Polish J. Chem. 82, 159–169 (2008) Google Scholar