ADSORPTION OF NONIONIC AND CATIONIC SURFACTANTS FROM AQUEOUS BINARY-MIXTURES ONTO THE SOLID/LIQUID INTERFACE

The effect of the cationic surfactant cetyltrimethylammonium bromide (CTAB) on the adsorption of the nonionic surfactant iso-nonilphenol ethoxylate with an average polyethylene oxide chain length of about 25 at the limestone/ solution interface was studied. The adsorption and effect of individual and mixed solutions of surfactants on the wetting behaviour of limestone surface was also studied. The results indicated that only CTAB was adsorbed onto the limestone surface from solutions of mixture surfactants. The results also showed that hydrophobization of the solid surface occurred at a very low concentration and then, as the concentration of surfactants increased it became hydrophilic.