Synthesis and Micellization properties of aquenous anionic surfactants: Sodium Dodecyl Sulfate (A Review)

Sodium Dodecyl Sulfate (SDS) is an organic compound surfactant used in many cleaning and hygiene products. Various parameters such as critical micelle concentration (CMC), surface excess, counter-ion binding constant, surface area studied as well as thermodynamic properties can effect on formation and characterization of anionic micelles. As a case study, synthesize of sodium dodecyl isosorbide sulfates showed 5-0 dodecyl isosorbide sulfate as it’s isomer is more efficient surfactant in comparison with 2-O-dodecyl isosorbide sulfate and It hold in fee simple a much lower critical micelle concentration (CMC) than sodium dodecyl sulfate. CDM 210 Conductometer equipped with conductivity cell was used to determine CMC and Bikerman’s test was used to understand the foaming properties of aqueous solutions of the compounds. The effect of counter-ions of surfactant for study on interfacial properties was possible by measuring foamability. Using various counter-ions, Lithium, Cesium and magnesium in compare with sodium ion show a decrease in Surface tension measurements as follow: LiDS>NaDS>CsDS>Mg(DS)(2). The thermodynamic activation parameters, free energy changed in present of Methanol, Ethanol, n-Propanoland iso-Propano.l A maximum increasing in free energy related to concentration of alcohol and it happens at 0.2-0.3 mole fraction of alcohols. The heights of the maxima are in the order: (iso-Propanol + aqueous SDS)> (n-propanol + aqueous SDS)> (Ethanol + aqueous SDS)> (Methanol + aqueous SDS). This work help to predict the properties of the surfactant solutions and results can enable us to understand the effect of micelaization parameters of SDS.

Keywords:

Sodium Dodecyl Sulfate (SDS) , Critical micelle concentration (CMC) , Counter-ion binding constant , Micelazation