Chemical Co-precipitation Synthesis of Manganese Ferrite (MnFe2O4) and Evaluation of Its Applications in Copper Removal from Aqueous Solutions

This study investigated the removal of copper from aqueous solutions using manganese ferrite (MnFe2O4) nanoparticles as a suitable and new adsorbent. For this purpose, manganese ferrite nanoparticles were synthesized by the co-precipitation method, and the effect of pH parameter, contact time, adsorbent concentration, as well as the influence of initial concentration on the copper adsorption process in the batch system were studied. To determine the properties of manganese ferrite nanoparticles, a scanning electron microscope, X-ray diffraction device, and infrared spectrometer were used. The results showed that the average size of these nanoparticles was between 30 and 50 nm. Moreover, it was indicated that by increasing the pH of the aqueous solution from 3 to 7, the adsorption capacity of copper increased so that at an optimal pH of 7, the adsorption rate reached more than 99%. Furthermore, increasing the contact time and the amount of adsorbent increased the removal efficiency, and the results revealed that with increasing the concentration of copper, the adsorption capacity increased. In the study of adsorption isotherms, the experimental data showed more agreement with the Freundlich model with an adsorption capacity of more than 199 mg/g. In addition, the data obtained for the adsorbent indicated that the copper adsorption follows the pseudo-second-order kinetic model. In general, the results of this study showed that the use of manganese dioxide nanoparticles is a suitable method with a high potential for removing copper from aqueous solutions.