Chain length effects on complex formation in solutions of sodium alkanoates and tetradecyl trimethyl ammonium bromide

► Description of the adsorption isotherms of individual and mixed solutions of C14TAB and various alkanoates using Frumkin and Lucassen-Reynders approaches. ► Complexes formation depends on the chain length of the anionic alkanoate. ► Surfactants with short carbon chains act as organic salts. ► 1:1 complexes dominate the whole adsorption behaviour of mixtures.