Significantly Improved Separation Efficiency of Refractory Weakly Magnetic Minerals by Pulsating High-Gradient Magnetic Separation Coupling with Magnetic Fluid

Abstract

High-gradient magnetic separation (HGMS) is indispensably applied in the rougher separation stage of refractory weakly magnetic minerals. The most difficult problem while processing refractory weakly magnetic minerals is the low selectivity of HGMS caused by the competing capture of magnetic valuable and gangue minerals. In this study, a paramagnetic fluid is introduced into HGMS and an innovative method, termed highgradient magnetic separation coupling with magnetic fluid (HGMSCMF), with a significantly high selectivity is proposed. A new competing force (magnetic repulsive force) generated by the magnetic fluid will enlarge the force difference of valuable and gangue minerals and improve selectivity. The relative magnetic force acting on the magnetic valuable and gangue minerals can be adjusted by varying the fluid volume susceptibility, with the optimal fluid susceptibility approaching that of gangue minerals. HGMSCMF experiments on an ilmenite ore using paramagnetic MnCl 2 solutions showed that the selectivity was remarkably improved by increasing MnCl 2 concentrations (fluid susceptibility). The TiO 2 grade and mass of magnetic products could be simultaneously improved by increasing the applied induction in HGMSCMF, whereas in conventional HGMS, the TiO 2 grade and recovery decreased and increased, respectively. HGMSCMF is applicable to various matrices (or separators), and a significantly improved TiO 2 grade (close to that of industrial concentrates) could be obtained with only one-stage HGMSCMF. The recycling of magnetic fluid and cost economy of HGMSCMF are also discussed and analyzed. HGMSCMF presents several advantages over conventional HGMS and has great application prospects for realizing the clean and efficient utilization of refractory weakly magnetic minerals or materials.

Biohydrometallurgy: Paving the Way for a Greener Future of Mineral Processing in Indonesia

“…This procedure is designed to enhance the surface area for ensuing the subsequent separation processes and to liberate the valuable minerals entrapped within the gangue materials. The ore subsequently undergoes concentration using techniques such as gravity separation, magnetic separation, flotation, and flocculation (Ankireddy et al, 2023;Diab et al, 2022;Kabatesi et al, 2022;Sanwani et al, 2015a;2015b;2015c;2015d;2015e;2016a;2016b;2021a;2021b;Teniola et al, 2022;Wahyuningsih et al, 2020;Wahyuningsih et al, 2018;Zheng et al, 2022). These methods serve to separate the valuable minerals from the gangue.…”

Novel rare earth separation using magnetic susceptibility difference

“…This work introduces a simple method for magnetic separation of different rare earth metal and oxide particle mixtures using ferrofluid and paramagnetic liquid. When the magnetization of slurry suspended liquid was increased, the paramagnetic TiO2 particles could be separated from other studied paramagnetic particles 11,12 . However, the magnetic separation of liberated rare earth mixtures has not been studied.…”

Effect of the number of magnetic matrices on particle capture in high gradient magnetic separation

“…High gradient magnetic separation (HGMS) is a physical separation method that has been widely used in many scientific research and industrial fields, including but not limited to mineral processing (Chen et al 2021, Xian et al 2022, Zheng et al 2022, pollutant treatment (Okamoto et al 2011, Nishimoto et al 2021, Okumura et al 2022, and biomass separation (Ueda et al 2010, Abdel Fattah et al 2016, Ebeler et al 2018.…”