XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3217
In all three samples, significant upgrading beyond the
tests without pre-treatment were found. This indicates that
selectivity and final C(T) recovery may not be dependent
on the sample chemical composition. Rather, the improved
flotation response may be due to improve liberation by
removing the binder with heat treatment prior to flotation.
This is indicated by: i) a higher rougher concentrate grade
found in both Sample A and C, ii) reduced cleaner losses
between stages, iii) increased upgrading by the cleaner
stages, and iv) significant reduction in cathodic metal
recoveries.
FLOTATION PRODUCT
CHARACTERIZATION
The 3rd cleaner concentrate and rougher tailings from
Sample B were subjected to particle size analysis and quali-
tatively observed using Hitachi SU5000 (Hitachi, Tokyo,
Japan) scanning electron microscope (SEM) operated at
20kV and equipped with an Oxford Instruments X-MaxN
80 mm energy dispersive X-ray (EDX) spectrometer.
Particle Size Analysis
Particle size analysis of the final concentrate and rougher
tailings with and without pre-treatment for Sample B is
shown in Figure 8 and Figure 9, respectively. Without pre-
treatment, finer particles were recovered as evidence by the
final concentrate having 80% passing 30µm where as the
rougher tailings exhibit a bi-modal particle distribution
potentially indicating finer graphite particles that were not
recovered and coarser but unliberated particles. In contrast,
both the final concentrate and rougher tailings with pre-
treatment exhibit similar particle size distribution. The final
concentrate and rougher tailings were found to be 80%
passing 67µm and 45µm, respectively. This indicates that
the binder was successfully removed with pre-treatment,
liberating the coarser particles joined by the binder.
Scanning Electron Microscopy
Scanning electron microscope was used to qualitatively
observed the final concentrate and rougher tailings without
pre-treatment from Sample B. As seen in Figure 10 and
Figure 11, the 3rd cleaner concentrate appeared to contain
less impurities to the rougher tailings, corresponding to
the elemental mass balance. Significant amount of impuri-
ties can still be found in the final concentrate. Beyond the
cathodic metals, connectors (both Al and Cu) were found
along with the steel casing as evidence by the presence of
Fe. These impurities may result in issues of anode fabrica-
tion or electrochemical performance. Further purification is
required in order for the graphite to be re-used in a battery.
CONCLUSIONS
The flotation response of three commercial lithium-ion
battery (LIB) recycled black mass, Sample A, B, and C,
were compared. The chemical composition varied sig-
nificantly where the as-received samples graded 37.1%
C(T) and 36.5% C(T) in Sample A and B, respectively.
Correspondingly, the total cathodic metals (Co, Li, Mn,
0
10
20
30
40
50
60
70
80
90
100
0
2
4
6
8
10
12
Diameter, μm
Sample B As-Is 3rd Cl Conc Sample B As-is Ro Tls
Sample B As-Is 3rd Cl Conc Sample B As-is Ro Tls
Figure 8. Particle size analysis of flotation products without pre-treatment (sample B)
0.51 0.766 1.151 1.729 2.599 3.905 5.867 8.816 13.246 19.904 29.907 44.938 67.523 101.46 152.453 229.075 344.206 517.2 777.141 1167.725
Cumulative
Passing
(%)
Fraction
(%)
In all three samples, significant upgrading beyond the
tests without pre-treatment were found. This indicates that
selectivity and final C(T) recovery may not be dependent
on the sample chemical composition. Rather, the improved
flotation response may be due to improve liberation by
removing the binder with heat treatment prior to flotation.
This is indicated by: i) a higher rougher concentrate grade
found in both Sample A and C, ii) reduced cleaner losses
between stages, iii) increased upgrading by the cleaner
stages, and iv) significant reduction in cathodic metal
recoveries.
FLOTATION PRODUCT
CHARACTERIZATION
The 3rd cleaner concentrate and rougher tailings from
Sample B were subjected to particle size analysis and quali-
tatively observed using Hitachi SU5000 (Hitachi, Tokyo,
Japan) scanning electron microscope (SEM) operated at
20kV and equipped with an Oxford Instruments X-MaxN
80 mm energy dispersive X-ray (EDX) spectrometer.
Particle Size Analysis
Particle size analysis of the final concentrate and rougher
tailings with and without pre-treatment for Sample B is
shown in Figure 8 and Figure 9, respectively. Without pre-
treatment, finer particles were recovered as evidence by the
final concentrate having 80% passing 30µm where as the
rougher tailings exhibit a bi-modal particle distribution
potentially indicating finer graphite particles that were not
recovered and coarser but unliberated particles. In contrast,
both the final concentrate and rougher tailings with pre-
treatment exhibit similar particle size distribution. The final
concentrate and rougher tailings were found to be 80%
passing 67µm and 45µm, respectively. This indicates that
the binder was successfully removed with pre-treatment,
liberating the coarser particles joined by the binder.
Scanning Electron Microscopy
Scanning electron microscope was used to qualitatively
observed the final concentrate and rougher tailings without
pre-treatment from Sample B. As seen in Figure 10 and
Figure 11, the 3rd cleaner concentrate appeared to contain
less impurities to the rougher tailings, corresponding to
the elemental mass balance. Significant amount of impuri-
ties can still be found in the final concentrate. Beyond the
cathodic metals, connectors (both Al and Cu) were found
along with the steel casing as evidence by the presence of
Fe. These impurities may result in issues of anode fabrica-
tion or electrochemical performance. Further purification is
required in order for the graphite to be re-used in a battery.
CONCLUSIONS
The flotation response of three commercial lithium-ion
battery (LIB) recycled black mass, Sample A, B, and C,
were compared. The chemical composition varied sig-
nificantly where the as-received samples graded 37.1%
C(T) and 36.5% C(T) in Sample A and B, respectively.
Correspondingly, the total cathodic metals (Co, Li, Mn,
0
10
20
30
40
50
60
70
80
90
100
0
2
4
6
8
10
12
Diameter, μm
Sample B As-Is 3rd Cl Conc Sample B As-is Ro Tls
Sample B As-Is 3rd Cl Conc Sample B As-is Ro Tls
Figure 8. Particle size analysis of flotation products without pre-treatment (sample B)
0.51 0.766 1.151 1.729 2.599 3.905 5.867 8.816 13.246 19.904 29.907 44.938 67.523 101.46 152.453 229.075 344.206 517.2 777.141 1167.725
Cumulative
Passing
(%)
Fraction
(%)