Porous fly ash geopolymer for the adsorption of anionic surfactant from aqueous solution

Abstract This paper describes the development of a porous geopolymer (PGP) to remove sodium dodecyl benzene sulfonate (SDBS) from model wastewater. The characterization results confirmed the synthesis of geopolymer. The surface of the geopolymer was porous and rough. The adsorbent dose- 0.5 g/L, SDBS concentration- 25 mg/L, pH 2, and 60 minutes of contact time were the optimal adsorption conditions. The Freundlich and Langmuir isotherm models best fit the data, showing that the SDBS adsorbed onto porous geopolymer through a combination of mono and multilayers by homogeneous and heterogeneous adsorption active sites on the geopolymer’s surface. A maximum of 200 mg/g adsorption capacity was obtained. This research confirmed that geopolymers can effectively adsorb anionic surfactants SDBS from aqueous solution.