Adsorption Analyses of Phenol from Aqueous Solutions Using Magadiite Modified with Organo-Functional Groups: Kinetic and Equilibrium Studies

Materials (Basel). 2018 Dec 28;12(1):96. doi: 10.3390/ma12010096.

Abstract

Organically-modified magadiite (MAG⁻CTAB⁻KH550) was synthesized via ion-exchange method and condensation reaction in the presence of pure magadiite (MAG), cetyltrimethylammonium bromide (CTAB) and γ-aminopropyltriethoxysilane (KH550) in aqueous solution in this research. This new adsorbent material was studied using scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), and N₂ adsorption/desorption isotherms process. It was found that the MAG⁻CTAB⁻KH550 has high Brunaur-Emmet-Teller (BET) specific surface area and mesoporous pore size distribution which enhanced its ability to remove phenol in aqueous solution; and, the value of pH has a relatively large impact on the adsorption behavior of the sorbent. Finally, the adsorptive behavior of the mesoporous material on phenol was followed pseudo-second-order kinetic adsorption model. In contrast, the adsorption equilibrium isotherm was better performed Langmuir isotherm model than the Freundlich isotherm model; in addition, the results also showed that the MAG⁻CTAB⁻KH550 had a better adsorption capacity and removal efficiency than MAG.

Keywords: adsorption; adsorption isotherms; adsorption kinetics; magadiite; phenol.