Rates of Adsorption of Sulphuric Acid by Wool in Presence of Anionic Surfactants

The addition of anionic surfactants to dilute aqueous solutions of sulphuric acid reduces the initial rate of adsorption of acid by wool but increases acid adsorption after a longer period of contact. The magnitude of these effects depends on the molecular weight and concentration of the surfactant, provided the latter is below the critical micelle concentration. An increase in surfactant concentration beyond the critical micelle concentration has little further effect on the rate of acid adsorption. An explanation is offered of the phenomena observed and the technological implications are discussed.