Settling velocity of a sodium montmorillonite floc under high ionic strength

The settling velocity of a single floc of sodium montmorillonite coagulated under a condition of high ionic strength was analyzed as a function of floc diameter to determine the fractal dimension of the floc. The obtained values of the fractal dimension were found to be approximately 2.0 irrespective of ionic strength and pH values. This result clearly demonstrated that the difference of the viscosity of coagulated montmorillonite suspension against ionic strength earlier reported is not affected by the difference of the fractal structure of a floc but by that of the attractive force between individual clay particles in a floc.