Electrokinetic studies of magnesium hydroxide.
The electrophoretic mobility of magnesium hydroxide was studied as a function of the concentration of its potential-determining ions, namely, of the magnesium ions, and of the hydroxide ions or pH. The zero point of charge was located at approximately 10.8. The zeta-potential of magnesium hydroxide below this pH was positive. The addition of magnesium nitrate to magnesium hydroxide suspensions increased the positive zeta-potential and lowered the pH. The low solubility of magnesium hydroxide in water prevented the attainment of substantial concentrations of magnesium ions in solution. Increasing the hydroxide-ion concentration or the pH produced charge inversion. The largest negative zeta-potential was attained at pH 11.5. Further increases in pH produced no significant increase in the negative value of the zeta-potential.
D055598:Chemical Phenomena; D002621:Chemistry; D004586:Electrophoresis / Q000379:methods; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008274:Magnesium / Q000032:analysis*; D008276:Magnesium Hydroxide / Q000032:analysis*
D008274:Magnesium; D008276:Magnesium Hydroxide