Synthesis of DNPH/SDS/Fe3O4 Nanoparticles for Removal of Cr (VI) Ions From Aqueous Solution

In this study, sodium dodecyl sulfate (SDS) coated magnetite modified with 2, 4-Dinitrophenylhydrazine was used to remove Cr (VI) ions from aqueous solution. The modified magnetite nanoparticles were characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and SEM–EDXS measurement. The synthesized nanoparticles exhibited a high surface area of 75.5 m² g⁻¹ and were of 20 - 35 nm in particle size. The effects of parameters, including pH, dose of adsorbent, temperature and contact time were investigated to find the optimum adsorption conditions. Adsorption data fits well with the Langmuir isotherm model with a maximum adsorption capacity (q_m) and a Langmuir adsorption equilibrium constant (b) of 169.5 mg g^-1 and 0.168 L mg^-1, respectively. The adsorption kinetic agrees well with pseudo-second-order model.