Adsorption equilibrium and kinetics on N-lauroyl-N-methylglucamide at air/water interface

Abstract

The adsorption equilibrium and kinetics of N-lauroyl-N-methylglucamide (MEGA-12) aqueous solution were studied. The critical micelle concentration, the maximum surface excess, and the minimum area per molecule of MEGA-12 were obtained as 2.48 × 10−4 mol/l, 4.883 × 10−6 mol/m2, and 0.34 nm2, respectively. The adsorption kinetics of MEGA-12 was studied by the maximum bubble pressure method. The result shows that in the initial stage or at small MEGA-12 concentrations, the adsorption process is diffusion-controlled; however, it changes to become adsorption-controlled at the end of the process. The effects of temperature, inorganic salts, alcohols, and ionic liquid on the adsorption kinetics were also discussed.