INFLUENCE OF TRANSPORT MECHANISM ON ADSORPTION OF INTERACTING COLLOIDPARTICLES

The localized irreversible adsorption of interacting colloid particles on homogeneous liquid/solid interfaces was analysed. The Monte Carlo and Brownian dynamics numerical approaches were used for simulating pa rticle adsorption kinetics as a function of the effective interaction range and the transport mechanism of the particles towards the interfa ce. The theoretical methods were used for interpreting the experimenta l results obtained in direct microscope observation cells under condit ions of electrostatic attraction between particles and interfaces. Mon odisperse suspensions of polystyrene and melamine latex particles (in the micrometre size range) were used in these experiments, with mica s heets as the adsorbing surface. It was found that the particle transpo rt mechanism exerts a profound effect on the structure of the adsorbed layer characterized by the pair correlation function. The experimenta l results were well accounted for by the Brownian dynamics simulation method. The simple random sequential adsorption model often used previ ously was found to be suitable for moderate flow rates. Our results sh owed also that the Langmuir model is not appropriate for describing th e localized adsorption of particles on homogeneous surfaces.