8
previous research by Yano, 2012, Steadman et al., 2021,
and Corchado &Alagha, 2023 suggested that Te, Au, Ag,
Cu, and other valuables are 90% locked within larger pyrite
grains as less than 20 µm in CT [26,33,34]. Therefore, this
research investigated the froth flotation process for pyrite
and other sulfides in CT using conventional reagents [31].
Subsequent baseline flotation experiments for pyrite
concentration improved recovery rates and established a
foundation for optimization research into other flotation
parameters. The most efficient reagent combinations were
identified, with 150 g/t SIPX and 50 g/t OREPREP X-237
yielding a 92.18% recovery for Te at a grade of 1.4 ppm,
demonstrating substantial improvement. Tellurium, gold,
and silver enrichments for the 150 g/t SIPX and 50 g/t
OREPREP X-237 were 3.08, 2.59, and 1.98, respectively.
Table 7 shows Te, Au, and Ag enrichment for the efficient
collector and frother combinations from the pyrite baseline
flotation experiments.
The introduction of a combination of gravity separa-
tion (GS) and froth flotation led to significant improve-
ments in the pyrite concentration process. GS effectively
removed gangue materials and enhanced the floatability
of pyrite, suggesting that valuable elements locked within
were enriched. Results indicated that the GS-C+M stream
should be used as the flotation feed for the subsequent flo-
tation experiments.
In the flotation experiments, remarkable improve-
ments were observed in Fe, Cu, and S recovery rates and
grades, taken as an indicator of major sulfide concentration
(pyrite and chalcopyrite). For instance, the GS 2-C+M had
the highest enrichment of 2.18, 6.77, and 4.94 for Fe, Cu,
and S, respectively. Therefore, these results suggested that
GS 2-C+M would have a higher enrichment in pyrite, chal-
copyrite, and associated Te-Au-Ag-bearing minerals. Table
8 shows the Fe, Cu, and S enrichment for preconcentration
and flotation experiments.
These results highlighted the success of the geometal-
lurgical research approach in enhancing the recovery and
the enrichment of Te, Au, and Ag from copper tailings,
potentially transforming previously discarded material into
a valuable resource.
0
10
20
30
40
0
20
40
60
80
100
Fe Cu S
Flotation -GS 2
Recovery Grade
Figure 6. Flotation recovery and grade of the concentrate
and middlings of gravity separation with a 1:10 S/L ratio.
0
10
20
30
40
0
20
40
60
80
100
Fe Cu S
Flotation -GS 3
Recovery Grade
Figure 7. Flotation recovery and grade of the concentrate
and middlings of gravity separation with a 1:5 S/L ratio
Table 7. Enrichment for Te, Au, and Ag for efficient collector and frother combinations
Baseline Flotation Conditions Te Au Ag
EXP300422 (120g/t) +MIBC (50g/t) 2.25 1.57 1.42
EXP300422 (150g/t) +MIBC (50g/t) 2.00 1.41 1.27
EXP300422 (150 g/t) +terpineol (50g/t) 3.00 1.28 1.74
EXP300422 (150 g/t) +OREPREP X-237 (50g/t) 3.25 2.46 1.82
SPIX (30g/t) +MIBC (50g/t) 2.05 1.96 1.32
SPIX (90 g/t) +OREPREP X-237 (50g/t) 3.50 1.90 2.26
SPIX (150 g/t) +OREPREP X-237 (50g/t) 3.08 2.59 t
SPIX (90 g/t) +terpineol (50g/t) 2.88 1.49 1.85
Table 8. Enrichment for Fe, Cu, and S for preconcentration
and flotation experiments
Gravity Separation and
Flotation Experiments Fe Cu S
Flotation -GS 1 -C+M 1.55 3.01 2.19
Flotation -GS 2 -C+M 2.18 6.77 4.94
Flotation -GS 3 -C+M 1.98 5.80 3.14
Grade
(wt.%)
Recovery
(%)
Grade
(wt.%)
Recovery
(%)
previous research by Yano, 2012, Steadman et al., 2021,
and Corchado &Alagha, 2023 suggested that Te, Au, Ag,
Cu, and other valuables are 90% locked within larger pyrite
grains as less than 20 µm in CT [26,33,34]. Therefore, this
research investigated the froth flotation process for pyrite
and other sulfides in CT using conventional reagents [31].
Subsequent baseline flotation experiments for pyrite
concentration improved recovery rates and established a
foundation for optimization research into other flotation
parameters. The most efficient reagent combinations were
identified, with 150 g/t SIPX and 50 g/t OREPREP X-237
yielding a 92.18% recovery for Te at a grade of 1.4 ppm,
demonstrating substantial improvement. Tellurium, gold,
and silver enrichments for the 150 g/t SIPX and 50 g/t
OREPREP X-237 were 3.08, 2.59, and 1.98, respectively.
Table 7 shows Te, Au, and Ag enrichment for the efficient
collector and frother combinations from the pyrite baseline
flotation experiments.
The introduction of a combination of gravity separa-
tion (GS) and froth flotation led to significant improve-
ments in the pyrite concentration process. GS effectively
removed gangue materials and enhanced the floatability
of pyrite, suggesting that valuable elements locked within
were enriched. Results indicated that the GS-C+M stream
should be used as the flotation feed for the subsequent flo-
tation experiments.
In the flotation experiments, remarkable improve-
ments were observed in Fe, Cu, and S recovery rates and
grades, taken as an indicator of major sulfide concentration
(pyrite and chalcopyrite). For instance, the GS 2-C+M had
the highest enrichment of 2.18, 6.77, and 4.94 for Fe, Cu,
and S, respectively. Therefore, these results suggested that
GS 2-C+M would have a higher enrichment in pyrite, chal-
copyrite, and associated Te-Au-Ag-bearing minerals. Table
8 shows the Fe, Cu, and S enrichment for preconcentration
and flotation experiments.
These results highlighted the success of the geometal-
lurgical research approach in enhancing the recovery and
the enrichment of Te, Au, and Ag from copper tailings,
potentially transforming previously discarded material into
a valuable resource.
0
10
20
30
40
0
20
40
60
80
100
Fe Cu S
Flotation -GS 2
Recovery Grade
Figure 6. Flotation recovery and grade of the concentrate
and middlings of gravity separation with a 1:10 S/L ratio.
0
10
20
30
40
0
20
40
60
80
100
Fe Cu S
Flotation -GS 3
Recovery Grade
Figure 7. Flotation recovery and grade of the concentrate
and middlings of gravity separation with a 1:5 S/L ratio
Table 7. Enrichment for Te, Au, and Ag for efficient collector and frother combinations
Baseline Flotation Conditions Te Au Ag
EXP300422 (120g/t) +MIBC (50g/t) 2.25 1.57 1.42
EXP300422 (150g/t) +MIBC (50g/t) 2.00 1.41 1.27
EXP300422 (150 g/t) +terpineol (50g/t) 3.00 1.28 1.74
EXP300422 (150 g/t) +OREPREP X-237 (50g/t) 3.25 2.46 1.82
SPIX (30g/t) +MIBC (50g/t) 2.05 1.96 1.32
SPIX (90 g/t) +OREPREP X-237 (50g/t) 3.50 1.90 2.26
SPIX (150 g/t) +OREPREP X-237 (50g/t) 3.08 2.59 t
SPIX (90 g/t) +terpineol (50g/t) 2.88 1.49 1.85
Table 8. Enrichment for Fe, Cu, and S for preconcentration
and flotation experiments
Gravity Separation and
Flotation Experiments Fe Cu S
Flotation -GS 1 -C+M 1.55 3.01 2.19
Flotation -GS 2 -C+M 2.18 6.77 4.94
Flotation -GS 3 -C+M 1.98 5.80 3.14
Grade
(wt.%)
Recovery
(%)
Grade
(wt.%)
Recovery
(%)