Magsorbents: Potential candidates in wastewater treatment technology - A review on the removal of methylene blue dye

In recent years, several industries release varying concentrations of dye-containing wastewater directly into the ecosystem and become the foremost environmental concern. The adsorption method has been recognized to be one of the most effective techniques for the remediation of wastewater. The great efforts have been made by scientists to produce highly selective, discerning, and effective adsorbents. The introduction of magnetic iron oxide nanoparticles to adsorbents has led to a new avenue in resolving water pollution problems and found to have predominant significance in the elimination of dyes more efficiently compared to traditional adsorbents. Due to their unique physicochemical properties, magnetized adsorbents (magsorbents) display high removal efficiency along with easy and fast separation of adsorbent from aqueous media simply by applying an external magnetic field. Such a facile route of separation is crucial to increase the overall efficiency of operation and has great importance for practical application. This review summarizes the notable works carried out on the application of magsorbents for the adsorptive removal of cationic methylene blue (MB) dye from wastewater. The detailed information on the BET surface area, point of zero charge, operational conditions, and results on isotherm, kinetic and thermodynamics as reported on different magsorbents have been compiled. The present paper was planned with the prime objective to make the scientists up-to-date and to provide the valuable information of the developments that have been made as yet for the elimination of MB dye from aqueous solution by employing a variety of magsorbents.