Equilibrium and kinetics of Safranin O dye adsorption on MgO decked multi-layered graphene

• MgO decked multi-layered graphene (MDMLG) is prepared by simple combustion process.
• MDMLG acts as an excellent adsorbent to remove Safranin O (SO) dye from water.
• Chemisorption is the major mode of adsorption of SO dye onto MDMLG.
• MDMLG is reusable and aids in SO dye regeneration.
• MDMLG is also found to remove a mixture of dyes from a real textile effluent.

MgO decked multi-layered graphene (MDMLG) is synthesized using a rudimentary combustion process involving ignition of Mg in the presence of dry ice. MDMLG is used as an adsorbent to remove Safranin O (SO) dye from water. Adsorption related experimental data is best fitted to Langmuir adsorption isotherm indicating that adsorption of SO dye onto MDMLG is uniform. Mono layer adsorption capacity of MDMLG is ∼3.92 × 10−4 mol/g. Mean adsorption energy is ∼36.23 kJ/mol indicating that chemisorption is the major mode of adsorption. Pseudo 2nd order rate equation best describes the adsorption kinetics of SO dye onto MDMLG. Regeneration of SO dye in ethanol is ∼73.5%, which also indicates chemisorption type adsorption. MDMLG is also found to remove a mixture of dyes from a real textile effluent.

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