Adsorption Characteristics of Surfactant on Slag in Alkali Activated Slag Cement System

Alkali activated slag cement was a new green cementing material with many performances. Whereas, high viscosity and bad workability of the fresh mixture were the matters to embarrass its application. For exploring the special superplasticizer, the adsorption characteristics of surfactant on slag was studied, by UV Vis Absorption Spectrum Method. The results showed, first, the adsorbed amount of cationic surfactant [CH3(CH2)11N(CH3)3]Cl was the highest value among the five surfactants, 12.8 mg/g. Second, the effect of alkali on the adsorbed amount of surfactant was complex. Cationic surfactant had cooperativity with alkali. But, adding water glass, the adsorbed amounts of the surfactants on slag were negative, because it was both colloid property and alkali solution property. Finally, the retarder of YP-3 made the adsorbed amount of ionic surfactant to increase, due to YP-3 contracted electric double layer in the surface of slag.