2
sites. However, despite this loss, these sources currently
make a minor contribution to the overall global Te supply.
To address both the scarcity of Te resources and the issue
of tailing pollution, there is a need for viable, efficient, and
cost-effective technologies for the recovery of Te from mine
tailings.
Over 90% of the global Te supply is derived from
anode slimes, a byproduct generated during the electrolytic
refining of copper [19]. In this process, an electric potential
is applied to copper anodes (99% pure copper), releas-
ing Cu2+ cations into the electrolyte. These cations migrate
and deposit on the cathode, resulting in the production of
copper metal with a purity exceeding 99.99%. Meanwhile,
insoluble impurities settle at the bottom of the tank, form-
ing anode slimes. A significant portion of Te, more than
98%, in the anode is insoluble in the electrolyte and, con-
sequently, is found in the anode slimes along with other
insoluble impurities [19, 20]. To evaluate how much Te
production can be enhanced, it is crucial to calculate how
much is potentially available from copper operations in
which Te is present but currently not recovered.
While several recent studies have discussed the recovery
of some critical minerals in tailing streams, [21, 22], there
is a conspicuous absence of comprehensive review reports
encompassing the existing techniques for extracting and
recovering tellurium from tailings generated during the
copper concentration and extractive metallurgy processes.
Hence, it is necessary to contribute to Te research by pro-
viding a comprehensive study that explores essential aspects
such as production, primary applications, available sources,
and separation techniques for extracting Te. This review
aims to provide a concise overview of the present status of
tellurium recovery from tailing streams, with a focus on the
latest and most notable achievements in this field. It also
covers challenges and opportunities in Te recovery, offering
a valuable reference for the full exploitation and utilization
of tailings and industrial development.
TAILING STREAMS OF COPPER
CONCENTRATION, SMELTING, AND
REFINING PROCESSES
Copper sulfides constitute the primary source of metal-
lic copper, comprising 80% of copper resources [23]. The
major copper sulfide ores include chalcopyrite (CuFeS2),
bornite (Cu5FeS4), covellite (CuS), and chalcocite (Cu2S).
Pyrite (FeS2) is the most abundant sulfide mineral and is
considered a gangue mineral in the flotation of copper sul-
fides. It gains significance only when associated with pre-
cious metals such as gold. Typically, copper concentrate
from sulfide ores is generated through comminution, clas-
sification, and flotation operations and it is subsequently
subjected to pyrometallurgical or hydrometallurgical pro-
cesses to remove impurities and extract the pure copper
metal [24]. Tailings are the solid and fluid products gener-
ated in mine, mineral processing, and extractive metallurgy
operations [25]. Figure 1 shows a generalized flowsheet of
the processing of copper sulfide ores.
The initial tailings generated in open pit and under-
ground mining operations consist of discarded rocks, over-
burden, and discharged water. Copper sulfide minerals are
typically concentrated through flotation processes, result-
ing in tailings that contain mainly gangue minerals [26].
Tailings are produced in extractive metallurgical processes
including slags, flue dust, slimes, and electrolyte solution.
They are generated during the extraction of pure copper
metal from high-grade copper concentrate [26].
As the metal markets continue to grow in both scope
and scale, the waste products and residues generated during
the entire extraction process evolved into valuable sources
of critical metals like Te. Reprocessing these waste materials
not only contributes to meeting the increasing demand for
critical metals in the future but also aligns with the broader
goal of transitioning the mining industry towards a circular
economy system.
Figure 1. Generalized flowsheet of different processes utilized to recover copper from copper
sulfide ores.
sites. However, despite this loss, these sources currently
make a minor contribution to the overall global Te supply.
To address both the scarcity of Te resources and the issue
of tailing pollution, there is a need for viable, efficient, and
cost-effective technologies for the recovery of Te from mine
tailings.
Over 90% of the global Te supply is derived from
anode slimes, a byproduct generated during the electrolytic
refining of copper [19]. In this process, an electric potential
is applied to copper anodes (99% pure copper), releas-
ing Cu2+ cations into the electrolyte. These cations migrate
and deposit on the cathode, resulting in the production of
copper metal with a purity exceeding 99.99%. Meanwhile,
insoluble impurities settle at the bottom of the tank, form-
ing anode slimes. A significant portion of Te, more than
98%, in the anode is insoluble in the electrolyte and, con-
sequently, is found in the anode slimes along with other
insoluble impurities [19, 20]. To evaluate how much Te
production can be enhanced, it is crucial to calculate how
much is potentially available from copper operations in
which Te is present but currently not recovered.
While several recent studies have discussed the recovery
of some critical minerals in tailing streams, [21, 22], there
is a conspicuous absence of comprehensive review reports
encompassing the existing techniques for extracting and
recovering tellurium from tailings generated during the
copper concentration and extractive metallurgy processes.
Hence, it is necessary to contribute to Te research by pro-
viding a comprehensive study that explores essential aspects
such as production, primary applications, available sources,
and separation techniques for extracting Te. This review
aims to provide a concise overview of the present status of
tellurium recovery from tailing streams, with a focus on the
latest and most notable achievements in this field. It also
covers challenges and opportunities in Te recovery, offering
a valuable reference for the full exploitation and utilization
of tailings and industrial development.
TAILING STREAMS OF COPPER
CONCENTRATION, SMELTING, AND
REFINING PROCESSES
Copper sulfides constitute the primary source of metal-
lic copper, comprising 80% of copper resources [23]. The
major copper sulfide ores include chalcopyrite (CuFeS2),
bornite (Cu5FeS4), covellite (CuS), and chalcocite (Cu2S).
Pyrite (FeS2) is the most abundant sulfide mineral and is
considered a gangue mineral in the flotation of copper sul-
fides. It gains significance only when associated with pre-
cious metals such as gold. Typically, copper concentrate
from sulfide ores is generated through comminution, clas-
sification, and flotation operations and it is subsequently
subjected to pyrometallurgical or hydrometallurgical pro-
cesses to remove impurities and extract the pure copper
metal [24]. Tailings are the solid and fluid products gener-
ated in mine, mineral processing, and extractive metallurgy
operations [25]. Figure 1 shows a generalized flowsheet of
the processing of copper sulfide ores.
The initial tailings generated in open pit and under-
ground mining operations consist of discarded rocks, over-
burden, and discharged water. Copper sulfide minerals are
typically concentrated through flotation processes, result-
ing in tailings that contain mainly gangue minerals [26].
Tailings are produced in extractive metallurgical processes
including slags, flue dust, slimes, and electrolyte solution.
They are generated during the extraction of pure copper
metal from high-grade copper concentrate [26].
As the metal markets continue to grow in both scope
and scale, the waste products and residues generated during
the entire extraction process evolved into valuable sources
of critical metals like Te. Reprocessing these waste materials
not only contributes to meeting the increasing demand for
critical metals in the future but also aligns with the broader
goal of transitioning the mining industry towards a circular
economy system.
Figure 1. Generalized flowsheet of different processes utilized to recover copper from copper
sulfide ores.