Synthesis and isotherm studies of nGO@nFe3O4 decorated with ZIF-8 for methylene blue removal

As the use of dyes in various industries has increased, environmental pollution has also increased due to the discharge of their wastewater into the waters. Here, the nanographene oxide@nano Fe3O4 (nGO@nFe3O4) decorated with ZIF-8 was synthesized to remove methylene blue from aqueous solutions. Physicochemical, thermal, morphological, and magnetic properties of ZIF-8@nGO@nFe3O4 nanocomposite adsorbent were characterized by standard analyses. SEM analysis show a porous structure and superposition of the layered structure of nGO@nFe3O4 which ZIF-8 was dispersed uniformly on or between the layers. Fine synthesis of the adsorbent was also confirm by FTIR. Results demonstrate the suitable growth of ZIF-8 on the surface of nGO@nFe3O4. The adsorbent possessed the appropriate magnetic ability and easily separated by a magnet. In addition, isotherm models of Langmuir, Freundlich, Temkin, and Redlich-Peterson were studied. Results show that Langmuir isotherm is the better model for describing the adsorption process, so, the adsorbent possesses a homogeneous surface, and the adsorption process is monolayer.