Controllable synthesis of cubic magnetic MgFe2O4 derived from MgFe-LDHs for efficient removal of methyl orange

A novel cubic magnetic MgFe2O4 derived from MgFe-layered double hydroxides (MgFe-LDHs) has been constructed by a combination of facile urea hydrothermal method and calcinations method and applied for the efficient removal of methyl orange (MO) with a maximum adsorption capacity of 535 mg g(-1) . The studies of formation mechanism of cubic MgFe-LDHs demonstrate the type of ferric salt and reaction time are two most important parameters influencing their cubic structures. Besides, calcinations temperature can not only decide magnetic performance of MgFe2O4, but also not change its cubic structure. Then the structural and surface properties of cubic magnetic MgFe2O4 were investigated by various characterization techniques. In addition, batch adsorption experiments were carried out to investigate the effects of different parameters such as the initial concentration of MO, pH, temperature and time on the adsorption behavior of MO on MgFe2O4. The kinetics, isotherm and thermodynamics of the adsorption of MO by MgFe2O4 were studied in detail. Moreover, adsorption mechanism of MO by MgFe2O4 was studied deeply. At last, MO could be desorbed from MgFe2O4 by 0.1 M NaOH solution and reused at least three times, indicating cubic magnetic MgFe2O4 is an effective and promising adsorbent for the removal of dye pollutants.

Automated summary

The novel cubic magnetic MgFe2O4 prepared from MgFe-layered double hydroxides showed high adsorption capacity for methyl orange (MO) removal. The formation mechanism, structural and surface properties, as well as adsorption behavior of the material were thoroughly studied. The adsorption kinetics, isotherm, thermodynamics, and desorption process of MO on MgFe2O4 were investigated, confirming its effectiveness as a promising adsorbent for dye pollutants removal.