3434 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
recovery of high purity manganese, say either chemically
such as by selective precipitation, or electrolytically.
Like other parts of this work, this part has generated
substantial data that would be useful in optimising this step
of the process. And like other parts of the work, there are
significant uncertainties in the analytical data owing to the
limitations of the analytical instruments, which were for
routine metallurgical testwork only. Notwithstanding, this
work has generated substantial data that would be useful in
developing an optimum flowsheet for producing HPMSM
with 4N purity.
POSSIBLE FLOWSHEET
Building on the present work, further testwork would be
carried out as part of an effort to develop an optimum
flowsheet. The following flowsheet (Figure 5) was reported
by Element 25 in 2023 from their feasibility study. We are
looking at simplifying this by incorporating precipitation,
re-leaching, solvent extraction and a number of crystalliza-
tion stages.
CONCLUSIONS
The work described herein is the first step in developing a
processing route for extracting and purifying the manga-
nese from a Pilbara manganese ore to produce a high purity
(99.99%) manganese sulfate monohydrate (4N HPMSM)
product. It explored the extraction of manganese from its
ore by reductive leaching and followed several separation
techniques to purify the resulting pregnant liquor stream.
The ore sample, which was a composite of several lots of
samples taken from the tenement contained mainly manga-
nese (40%), iron (12%) and Si (4.8%), which is equivalent
to 64% MnO2, 18% Fe2O3 and 10% SiO2. Following are
the major findings:
• Reductive leaching of the composite using sulfur
dioxide (SO2) as reductant yielded more than 99%
manganese dissolution but generated a highly con-
taminated pregnant liquor solution (PLS) with iron
(11.3 g/L) and aluminium (1.9 g/L) constituting the
bulk of the impurities. Thus, the purifying step will
determine the viability of the process.
• An attempt to precipitate the iron at low temperature
as hematite yielded essentially complete precipitation
Figure 5. Flowsheet for producing HPMSM (https://www.element25.com.au/site/content/)
recovery of high purity manganese, say either chemically
such as by selective precipitation, or electrolytically.
Like other parts of this work, this part has generated
substantial data that would be useful in optimising this step
of the process. And like other parts of the work, there are
significant uncertainties in the analytical data owing to the
limitations of the analytical instruments, which were for
routine metallurgical testwork only. Notwithstanding, this
work has generated substantial data that would be useful in
developing an optimum flowsheet for producing HPMSM
with 4N purity.
POSSIBLE FLOWSHEET
Building on the present work, further testwork would be
carried out as part of an effort to develop an optimum
flowsheet. The following flowsheet (Figure 5) was reported
by Element 25 in 2023 from their feasibility study. We are
looking at simplifying this by incorporating precipitation,
re-leaching, solvent extraction and a number of crystalliza-
tion stages.
CONCLUSIONS
The work described herein is the first step in developing a
processing route for extracting and purifying the manga-
nese from a Pilbara manganese ore to produce a high purity
(99.99%) manganese sulfate monohydrate (4N HPMSM)
product. It explored the extraction of manganese from its
ore by reductive leaching and followed several separation
techniques to purify the resulting pregnant liquor stream.
The ore sample, which was a composite of several lots of
samples taken from the tenement contained mainly manga-
nese (40%), iron (12%) and Si (4.8%), which is equivalent
to 64% MnO2, 18% Fe2O3 and 10% SiO2. Following are
the major findings:
• Reductive leaching of the composite using sulfur
dioxide (SO2) as reductant yielded more than 99%
manganese dissolution but generated a highly con-
taminated pregnant liquor solution (PLS) with iron
(11.3 g/L) and aluminium (1.9 g/L) constituting the
bulk of the impurities. Thus, the purifying step will
determine the viability of the process.
• An attempt to precipitate the iron at low temperature
as hematite yielded essentially complete precipitation
Figure 5. Flowsheet for producing HPMSM (https://www.element25.com.au/site/content/)