1918
Efficient Enrichment of Iron Concentrate from Oolitic Hematite
by Minerals Phase Transformation
Haoyuan Ding, Shuai Yuan, Ruofeng Wang, Honghao Zhang, Yanjun Li, Peng Gao
College of Resources and Civil Engineering, Northeastern University, Shenyang, P.R. China
National-local Joint Engineering Research Center of High-efficient exploitation technology for
Refractory Iron Ore Resources, Shenyang, P.R. China
ABSTRACT: Oolitic hematite, a distinctive subset of iron ores with characteristics of micro-fine dissemination,
poses challenges for efficient utilization through traditional beneficiation methods. In this study, the process
of minerals phase transformation and magnetic separation was applied to enrich iron from oolitic hematite.
The optimal conditions of reduction temperature at 540 °C, the reduction time at 40 min, the reductant
concentration at 30%, and hydrogen as a reductant were investigated, in which the iron concentrate was obtained
with an iron grade of 56.84% and iron recovery of 96.31%. The underlying mechanism was investigated
via X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), X-ray Photoelectron Spectroscopy
(XPS), and Vibrating Sample Magnetometer (VSM). The magnetization of the sample increased from 0.2079
A·m2·kg–1 to 28.7436 A·m2·kg–1 after minerals phase transformation. The synergistic regulation of minerals
phase transformation and differential thermal expansion among minerals facilitates the generation of cracks and
fractures that deepen toward the core.
Keywords: Minerals phase transformation Oolitic hematite Magnetic properties Microstructure
INTRODUCTION
With the rapid development of the steel industry (Wenlong,
L., et al., 2022), the steel consumption pattern is on an
increasing trend to meet energy and economic demands
(Yufeng, C., et al., 2021 Xinyu, Z., et al., 2021), leading
to the depletion of high-grade iron ores. Therefore, the uti-
lization of refractory ores is of great significance (Padhi, M.,
et al., 2022.). Oolitic hematite, characterized by micro-fine
dissemination and wrapping with apatite and hematite, is
recognized as one of the most refractory iron ores (Keith,
Q. 2018 Neisiani, A.A., et al., 2023). The distinctive struc-
ture of oolitic hematite hinders the monomer dissociation
of gangue and iron minerals. As a result, developing various
technologies for oolitic hematite is crucial for achieving
effective utilization.
Numerous processes have been devised to enhance iron
enrichment from oolitic hematite (Jianwen, Y., et al., 2017
Hanquan, Z., et al., 2022.). The various beneficiation
methods primarily include traditional beneficiation, hydro-
metallurgy, and pyrometallurgy (Hossein, A.,et al., 2018
Liangping, X., et al., 2023). Zhiqiang, R., et al. (Zhiqiang,
R. et al., 2013) selected a cationic collector comprising
primary, secondary, and tertiary amines for oolitic hema-
tite. The iron concentrate was obtained with an iron grade
of 58.12% and recovery more than 96.04%. However,
achieving monomer dissociation between iron minerals
and gangue remains challenging. Therefore, traditional
Efficient Enrichment of Iron Concentrate from Oolitic Hematite
by Minerals Phase Transformation
Haoyuan Ding, Shuai Yuan, Ruofeng Wang, Honghao Zhang, Yanjun Li, Peng Gao
College of Resources and Civil Engineering, Northeastern University, Shenyang, P.R. China
National-local Joint Engineering Research Center of High-efficient exploitation technology for
Refractory Iron Ore Resources, Shenyang, P.R. China
ABSTRACT: Oolitic hematite, a distinctive subset of iron ores with characteristics of micro-fine dissemination,
poses challenges for efficient utilization through traditional beneficiation methods. In this study, the process
of minerals phase transformation and magnetic separation was applied to enrich iron from oolitic hematite.
The optimal conditions of reduction temperature at 540 °C, the reduction time at 40 min, the reductant
concentration at 30%, and hydrogen as a reductant were investigated, in which the iron concentrate was obtained
with an iron grade of 56.84% and iron recovery of 96.31%. The underlying mechanism was investigated
via X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), X-ray Photoelectron Spectroscopy
(XPS), and Vibrating Sample Magnetometer (VSM). The magnetization of the sample increased from 0.2079
A·m2·kg–1 to 28.7436 A·m2·kg–1 after minerals phase transformation. The synergistic regulation of minerals
phase transformation and differential thermal expansion among minerals facilitates the generation of cracks and
fractures that deepen toward the core.
Keywords: Minerals phase transformation Oolitic hematite Magnetic properties Microstructure
INTRODUCTION
With the rapid development of the steel industry (Wenlong,
L., et al., 2022), the steel consumption pattern is on an
increasing trend to meet energy and economic demands
(Yufeng, C., et al., 2021 Xinyu, Z., et al., 2021), leading
to the depletion of high-grade iron ores. Therefore, the uti-
lization of refractory ores is of great significance (Padhi, M.,
et al., 2022.). Oolitic hematite, characterized by micro-fine
dissemination and wrapping with apatite and hematite, is
recognized as one of the most refractory iron ores (Keith,
Q. 2018 Neisiani, A.A., et al., 2023). The distinctive struc-
ture of oolitic hematite hinders the monomer dissociation
of gangue and iron minerals. As a result, developing various
technologies for oolitic hematite is crucial for achieving
effective utilization.
Numerous processes have been devised to enhance iron
enrichment from oolitic hematite (Jianwen, Y., et al., 2017
Hanquan, Z., et al., 2022.). The various beneficiation
methods primarily include traditional beneficiation, hydro-
metallurgy, and pyrometallurgy (Hossein, A.,et al., 2018
Liangping, X., et al., 2023). Zhiqiang, R., et al. (Zhiqiang,
R. et al., 2013) selected a cationic collector comprising
primary, secondary, and tertiary amines for oolitic hema-
tite. The iron concentrate was obtained with an iron grade
of 58.12% and recovery more than 96.04%. However,
achieving monomer dissociation between iron minerals
and gangue remains challenging. Therefore, traditional