Removal of nitrobenzene from aqueous solution using manganese ferrite nanoparticles

Abstract

Magnetic manganese ferrite (MnFe2O4) nanoparticles were successfully synthesized via a chemical co-precipitation route. The samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopies (SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and N2 adsorption-desorption isotherms. MnFe2O4 nanoparticles showed effective adsorption of nitrobenzene from an aqueous solution. The Langmuir and D-R models were well-described adsorption isotherms. The maximum adsorption capacity (qmax) of nitrobenzene onto MnFe2O4 was found to be 64.37 mg/g. The pseudo-second model was the most suitable for the fitting of the experimental kinetic data. The equilibrium adsorption capacity (qe) of MnFe2O4 was 50 mg/g. Thermodynamics data showed nitrobenzene adsorption was spontaneous, and exothermic, with decreased randomness. The regeneration cycle showed that the prepared sample has 80% adsorption capacity after five times adsorption–desorption cycles. MnFe2O4 nanoparticles can be used as a low-cost alternative to commercial for the adsorption of nitrobenzene from an aqueous solution.