An efficient and green method to separate iron and manganese from ferromanganese ore by suspension magnetization roasting and magnetic separation

Abstract

Despite the rich reserves of ferromanganese ore, it can only be discarded as waste rock due to the difficulty of its development and the unavailability of conventional methods. In this study, suspension magnetization roasting (SMR) and low-intensity magnetic separation (LIMS) were used to process ferromanganese ore. Under the optimum conditions, magnetic products with an iron grade of 69.66% at an iron recovery of 98.17% and nonmagnetic products with a manganese grade of 51.60% at a manganese recovery of 88.48% were obtained. X-ray diffraction (XRD), vibrating sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy and energy-dispersive spectrometry (SEM–EDS) were used to analyze the process mechanism. The data show that the newly generated products had greatly enhanced magnetic properties and that the surface became rougher and more porous after SMR-LIMS. Finally, hematite was transformed into magnetite in the magnetic product, and other minerals were transformed into the nonmagnetic product, realizing no tailing recycling or utilization.