Magnetic composite an environmental super adsorbent for dye sequestration – A review

• Extensive literature information on dye removal using magnetic composites (MCs) and magnetic nanocomposites (MNCs).
• Adsorption reaction kinetics, isotherms and diffusion models were reviewed.
• Outline of preparation techniques, magnetic behavior and characteristic features of MCs and MNCs were discussed.
• The outlook for potential applications was also discussed.

Adsorption is the most extensively used technique for dye sequestration. Magnetic separation of toxic pollutant is becoming a potential method in waste water purification and found to have predominant significance in the removal of dyes more effectively compared to conventional method of treatments. Numerous natural and synthetic adsorbents were used, out of which magnetic composites (MCs) and magnetic nanocomposites (MNCs) have gained much attention presently in the removal of dyes from aqueous solution. Abundant references are existing pertaining to synthesis of various magnetic composites and its application in adsorption of dyes. This report displays the exploitation of MCs and MNCs for adsorption of dyes, hazards posed by dyes, sorption mechanism, preparation methods, magnetic behavior and characteristics of magnetized particles with the relevant literature on the basic principle of adsorption using MCs and MNCs for separation of dyes under optimum physicochemical condition. Adsorption reaction model, diffusion model and isotherms which facilitate in understanding the reaction mechanism between adsorbent and adsorbate are concisely discussed.