Kinetics and equilibrium studies of methylene blue adsorption on 2D nanolamellar Fe3O4

ABSTRACT

Nanolamellar Fe₃O₄ as magnetic adsorbents was prepared using sodium dodecyl sulfonate as a template. Thermogravimetric measurements characterisation showed that the as-synthesised product contained about 6 wt% sodium dodecyl sulfonate. The adsorption performance of nanolamellar Fe₃O₄ for the removal of organic dye from aqueous solution was evaluated using methylene blue as a model dye. The product exhibited an excellent ability to adsorb methylene blue from aqueous solutions with a maximum methylene blue removal rate of 96.8%. The adsorption kinetics can be described by a pseudo-second-order equation, and the adsorption isotherm agreed well with Langmuir adsorption equation. Furthermore, the dye saturated nanolamellar Fe₃O₄ could be regenerated using acidic ethanol solution, and the nanolamellar Fe₃O₄ showed excellent reusability. The results indicate the potential use of the adsorbent for the removal of methylene blue from aqueous solution.