Abstract
Adsorption of surfactants on barite from aqueous solution is of interest for flotation and purification processes. A study of the adsorption of the anionic/nonionic surfactant mixture C-10 H21N2 phi SO3(ANO)/C-9 phi E-(12) (ETH) on barite showed that the adsorption isotherm of the nonionic C-9 phi E-(12) (ETH) was altered by the anionic, C-10 H21N2 phi SO3(ANO). Although the adsorption of the anionic was affected by the nonionic surfactant and enhanced its isotherm. The reason for this is associated with change in the micelle composition. Variations of the surface tension of the anionic/nonionic mixed surfactant systems against mole fraction changes were studied. Physical parameters, particularly maximum adsorption density Gamma(max), area occupied per molecules, activity coefficients, and free energy of micelle were also investigated. The adsorption isotherm was analyzed, these parameters confirm that the synergistic action of mixed micelle as collector for barite depends on its mole fraction. The optimum recovery of barite was obtained with 0.8 mol fraction. The results were discussed according to the obtained physical properties of the system at solution/air and barite/liquid interfaces.