Adsorption of surfactants on mineral oxide surfaces from aqueous solutions: II: Binary mixtures of anionic surfactants

摘要: Abstract Individual surfactant adsorption was measured for well defined mixtures of two isomerically pure alkylbenzene sulfonates adsorbing from aqueous solutions onto both alumina and kaolinite. An model, which includes two-dimensional phase transitions resulting lateral interactions, is shown to describe the observed isotherms. The result in formation mixed hemimicelles (high-density aggregates on surface). environment methylene groups hemimicelle slightly less favorable than that either hemimicelle. For solution compositions below Critical Micelle Concentration (CMC), having least tendency adsorb exhibits greatly increased because presence hemimicelles. greatest not different component adsorption. Since only monomer adsorbs significantly, monomer-micelle equilibrium had be considered simultaneously with model predict results above CMC. Ideal theory a good approximation this equilibrium. Above CMC, conditions are described minima maxima total