XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 1925
Magnetic property analysis
The magnetization and magnetic susceptibility of the sam-
ples were examined, as shown in Figure 9(a) and (b). As the
external magnetic field intensity increased to 600 kA·m–1,
the magnetization of the raw ore, concentrate, tailing,
and reduction product increased rapidly and then stabi-
lized, reaching a maximum value. Meanwhile, the specific
magnetization susceptibility of the four samples increased
rapidly and decreased. The magnetization and specific mag-
netization susceptibility of the raw ore reached the maxi-
mum value of 0.2079 A·m2·kg–1, 0.0019×10–3 m3·kg–1,
respectively. With the increase of external magnetic field,
the magnetization and specific magnetization susceptibility
of the reduction product rapidly increased, reaching a maxi-
mal value at 28.7436 A·m2·kg–1 and 0.1975×10–3 m3·kg–1,
respectively. This indicates that weak magnetic iron min-
erals (Fe2O3) were transformed into strong magnetic iron
minerals (Fe3O4) (Qiang, Z., et al., 2022). In comparison
to the reduction product, the concentrate exhibited further
increases in magnetization and specific magnetization sus-
ceptibility at 29.2816 A·m2·kg–1 and 0.2149×10–3 m3·kg–
1, respectively, demonstrating that strong magnetic iron
minerals were further enriched in the concentrate by mag-
netic separation (Zhidong, T., et al., 2022). The tailings,
containing weak magnetic iron minerals (Fe2O3) as identi-
fied by XRD, the magnetization and specific magnetization
susceptibility of the tailing increased at 2.2580 A·m2·kg–1,
0.0148×10–3 m3·kg–1, respectively. The results illustrate
that the magnetic properties of the samples were increased
by minerals phase transformation.
Surface element analysis
To gain an in-depth understanding of the transformation
from hematite to magnetite, the reduction product and
raw ore were performed to characterize the surface chemi-
cal composition and the chemical valence state of iron ele-
ments by XPS, as illustrated in Figure 10.
Figure 10(a) and (b) indicated that the XPS survey
spectra of raw ore and reduction product were identified. As
shown in Figure 10(c) and (d), Fe2p photo-emission lines
from the raw ore indicated that the binding energy of the
Fe2p3/2 peak and Fe2p1/2 peak of the raw ore at 710.80 eV
and 724.00 eV, and that of peaks corresponded to the
Fe3+-O bonds, indicating that the iron minerals on the sur-
face of the raw ore belonged to hematite, which were con-
sistent with the results of XRD containing Fe2O3 (Shuai,
Y., et al., 2023). Due to spin–orbit coupling, each spectrum
was split into two peaks, with an intensity ratio close to
2/1. The binding energy of the Fe2p3/2 peak and Fe2p1/2
peak of the reduction product reached at 709.60 eV and
723.50 eV, showing significant changes compared to the
raw ore. binding energy of the Fe2p3/2 peak and Fe2p1/2
peak of the reduction product demonstrated that the
mixture of states contains Fe2+, It indicated that Fe3+ was
transformed to Fe2+ during minerals phase transformation
(Wentao, Z., et al., 2021). XPS analysis indicate that iron
element in the raw ore and reduction product exist in the
form of hematite (Fe2O3), magnetite (Fe3O4), respectively,
indicating that hematite was transformed into magnetite by
minerals phase transformation, and this was corresponded
to the results of the experiment
Figure 9. Magnetic analysis of products at different stages: magnetization (a) magnetic susceptibility (b)
Magnetic property analysis
The magnetization and magnetic susceptibility of the sam-
ples were examined, as shown in Figure 9(a) and (b). As the
external magnetic field intensity increased to 600 kA·m–1,
the magnetization of the raw ore, concentrate, tailing,
and reduction product increased rapidly and then stabi-
lized, reaching a maximum value. Meanwhile, the specific
magnetization susceptibility of the four samples increased
rapidly and decreased. The magnetization and specific mag-
netization susceptibility of the raw ore reached the maxi-
mum value of 0.2079 A·m2·kg–1, 0.0019×10–3 m3·kg–1,
respectively. With the increase of external magnetic field,
the magnetization and specific magnetization susceptibility
of the reduction product rapidly increased, reaching a maxi-
mal value at 28.7436 A·m2·kg–1 and 0.1975×10–3 m3·kg–1,
respectively. This indicates that weak magnetic iron min-
erals (Fe2O3) were transformed into strong magnetic iron
minerals (Fe3O4) (Qiang, Z., et al., 2022). In comparison
to the reduction product, the concentrate exhibited further
increases in magnetization and specific magnetization sus-
ceptibility at 29.2816 A·m2·kg–1 and 0.2149×10–3 m3·kg–
1, respectively, demonstrating that strong magnetic iron
minerals were further enriched in the concentrate by mag-
netic separation (Zhidong, T., et al., 2022). The tailings,
containing weak magnetic iron minerals (Fe2O3) as identi-
fied by XRD, the magnetization and specific magnetization
susceptibility of the tailing increased at 2.2580 A·m2·kg–1,
0.0148×10–3 m3·kg–1, respectively. The results illustrate
that the magnetic properties of the samples were increased
by minerals phase transformation.
Surface element analysis
To gain an in-depth understanding of the transformation
from hematite to magnetite, the reduction product and
raw ore were performed to characterize the surface chemi-
cal composition and the chemical valence state of iron ele-
ments by XPS, as illustrated in Figure 10.
Figure 10(a) and (b) indicated that the XPS survey
spectra of raw ore and reduction product were identified. As
shown in Figure 10(c) and (d), Fe2p photo-emission lines
from the raw ore indicated that the binding energy of the
Fe2p3/2 peak and Fe2p1/2 peak of the raw ore at 710.80 eV
and 724.00 eV, and that of peaks corresponded to the
Fe3+-O bonds, indicating that the iron minerals on the sur-
face of the raw ore belonged to hematite, which were con-
sistent with the results of XRD containing Fe2O3 (Shuai,
Y., et al., 2023). Due to spin–orbit coupling, each spectrum
was split into two peaks, with an intensity ratio close to
2/1. The binding energy of the Fe2p3/2 peak and Fe2p1/2
peak of the reduction product reached at 709.60 eV and
723.50 eV, showing significant changes compared to the
raw ore. binding energy of the Fe2p3/2 peak and Fe2p1/2
peak of the reduction product demonstrated that the
mixture of states contains Fe2+, It indicated that Fe3+ was
transformed to Fe2+ during minerals phase transformation
(Wentao, Z., et al., 2021). XPS analysis indicate that iron
element in the raw ore and reduction product exist in the
form of hematite (Fe2O3), magnetite (Fe3O4), respectively,
indicating that hematite was transformed into magnetite by
minerals phase transformation, and this was corresponded
to the results of the experiment
Figure 9. Magnetic analysis of products at different stages: magnetization (a) magnetic susceptibility (b)