Removal of malachite green from aqueous solution by magnetic CuFe2O4 nano‑adsorbent synthesized by one pot solution combustion method

In the present investigation nano copper ferrite, CuFe2O4 (CF) is synthesized by one pot energy saving solution combustion synthesis. The combustion derived copper ferrite nanoadsorbent is characterized by powder X-ray diffraction, Fourier transform infra-red spectroscopy, scanning electron microscopy, transmission electron microscopy and UV–Vis spectroscopy. The magnetic behavior is studied by Vibrating sample magnetometer measurements and the results shows it’s a soft ferromagnet with low saturation magnetization and coercive effect. CF nanopowder is used as good magnetically separable nanoadsorbent. Adsorption property is evaluated by the removal of malachite green, a dye which is widely used by many industries, from its aqueous solution. Various parameters like contact time (5–30 min), adsorbent loading (0–45 mg) are investigated systematically by batch experiments. Adsorption isotherms and kinetic studies also conducted which shows that the adsorption follows pseudo second order mechanism. The experimental data fitted well with the Langmuir isotherm (R2 = 0.978), yielding a maximum adsorption capacity of 22 mg/g. The optimum adsorbent dose was found to be 40 mg/L and stirring time experiment reveals that 85% of decolourization was observed for 30 min of stirring at neutral pH which is much more efficient than those reported in literature.