XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3155
flotation performance of chalcopyrite, providing a founda-
tion for tailoring flotation strategies based on controlled
pulp chemistry conditions. The observed trends underscore
the significance of understanding noble character dynam-
ics in optimizing mineral separation processes, with poten-
tial implications for enhancing efficiency in chalcopyrite
recovery.
Implication of Galvanic Interactions and Pulp
Chemistry Influence on the Optimization of
Chalcopyrite Flotation
Achieving optimum flotation response of chalcopyrite
requires a comprehensive examination of several physi-
cochemical factors such as galvanic interactions and pulp
chemistry. A detailed consideration of these factors pro-
vides fundamental understanding of the selective separa-
tion mechanisms in chalcopyrite flotation. The results of
this study elucidate the combined influence of galvanic
interactions with pyrrhotite superstructures and change in
pulp chemistry (pH and ORP) on the flotation behaviour
of chalcopyrite. A key indicator was the observed correla-
tion between alterations in pulp chemistry and the type of
pyrrhotite present in the processing stream, showcasing the
potential to influence and predict chalcopyrite response
using pulp chemistry. The intrinsic noble character altera-
tion of chalcopyrite, along with the modification of its sur-
face species, leads to noticeable changes in its interaction
with the collector, ultimately resulting in an adverse impact
on flotation performance.
Such nuanced exploration of the galvanic interactions
and pulp chemistry helps make an in-depth understand-
ing of the underlying mechanisms and thus makes neces-
sary precise and optimally targeted modifications to the
metallurgical operation conditions. Fine tuning of pulp
chemistry emerges as an underpinning in the process where
adjustments of parameters like pH and oxidation reduction
potential (ORP) plays a critical role. For good chalcopy-
rite flotation performance, some proposal can be made that
there should be a balance between factors discussed early at
pH 9.5 with an ORP of –165 mV. Furthermore, our study
illustrates that the practical implications on how operators
identify and mitigate the distinct impact of the various pyr-
rhotite types on the chalcopyrite flotation. Monoclinic pyr-
rhotite, shows the greatest hindrance towards chalcopyrite
recovery. To that effect, it becomes imperative that strate-
gies are tailored towards minimizing their presence or miti-
gating the adverse effects of monoclinic pyrrhotite. This can
be achieved through selective ore blending, processing of a
selected part of ore grade, or invention of special reagents
that would counteract deleterious effect of monoclinic
pyrrhotite. Overcoming those problems with chalcopyrite
flotation at the source will enable enhancement of efficiency
and general performance of a chalcopyrite flotation process
by the operators.
Despite the optimization of pulp chemistry, the need
for dedicated measures to address the persistent influence
of galvanic interactions is evident. Hence those techniques
that would modify collector formulations or introduce def-
inite additives special for counteraction to galvanic effects
can be considered. Recognition of this prompts a paradigm
shift towards encouraging operators to view galvanic inter-
actions not merely as an inherent by-product but rather as
a controllable variable that can be strategically managed
for improved flotation outcomes. The practical implica-
tions are not confined within theoretical understanding but
extend over a roadmap to implement tangible and targeted
strategies in the field for efficacious and sustainable chalco-
pyrite flotation processes in application aspects.
CONCLUSION
This study offers improved theoretical understanding of the
complex processes influencing chalcopyrite flotation under
various pulp chemistry conditions in the presences of dif-
ferent pyrrhotite superstructures. Based on observations
from different experimental tests evaluating flotation per-
formance, collector adsorption, and electrochemical behav-
iour, the study draws the following conclusions:
1. Optimization of chalcopyrite flotation requires a
detailed understanding of optimum pulp chemis-
try variables such as pH and redox potential, as
minor alterations in these variables show a procliv-
ity to impact performance.
2. Mineralogical characteristics of associated sulphide
minerals (such as pyrrhotite) in pulp played a sig-
nificant role due to variations in the influence of
galvanic interactions as a function of the type of
pyrrhotite superstructure present.
3. Even at the established optimum pulp chemistry
variables (pH and redox potential), the presence
of pyrrhotite negatively impacted chalcopyrite flo-
tation performance, with monoclinic pyrrhotite
being more deleterious than hexagonal pyrrhotite.
4. Both a decrease in pulp chemistry (to pH 9 and
redox potential of –275 mV) and the presence of
monoclinic pyrrhotite induce the greatest reduc-
tion of the noble character of chalcopyrite, ulti-
mately increasing its rate of oxidation.
5. The correlation between flotation performance and
electrochemical behaviour suggests that consider-
ing both pulp chemistry and galvanic interactions
flotation performance of chalcopyrite, providing a founda-
tion for tailoring flotation strategies based on controlled
pulp chemistry conditions. The observed trends underscore
the significance of understanding noble character dynam-
ics in optimizing mineral separation processes, with poten-
tial implications for enhancing efficiency in chalcopyrite
recovery.
Implication of Galvanic Interactions and Pulp
Chemistry Influence on the Optimization of
Chalcopyrite Flotation
Achieving optimum flotation response of chalcopyrite
requires a comprehensive examination of several physi-
cochemical factors such as galvanic interactions and pulp
chemistry. A detailed consideration of these factors pro-
vides fundamental understanding of the selective separa-
tion mechanisms in chalcopyrite flotation. The results of
this study elucidate the combined influence of galvanic
interactions with pyrrhotite superstructures and change in
pulp chemistry (pH and ORP) on the flotation behaviour
of chalcopyrite. A key indicator was the observed correla-
tion between alterations in pulp chemistry and the type of
pyrrhotite present in the processing stream, showcasing the
potential to influence and predict chalcopyrite response
using pulp chemistry. The intrinsic noble character altera-
tion of chalcopyrite, along with the modification of its sur-
face species, leads to noticeable changes in its interaction
with the collector, ultimately resulting in an adverse impact
on flotation performance.
Such nuanced exploration of the galvanic interactions
and pulp chemistry helps make an in-depth understand-
ing of the underlying mechanisms and thus makes neces-
sary precise and optimally targeted modifications to the
metallurgical operation conditions. Fine tuning of pulp
chemistry emerges as an underpinning in the process where
adjustments of parameters like pH and oxidation reduction
potential (ORP) plays a critical role. For good chalcopy-
rite flotation performance, some proposal can be made that
there should be a balance between factors discussed early at
pH 9.5 with an ORP of –165 mV. Furthermore, our study
illustrates that the practical implications on how operators
identify and mitigate the distinct impact of the various pyr-
rhotite types on the chalcopyrite flotation. Monoclinic pyr-
rhotite, shows the greatest hindrance towards chalcopyrite
recovery. To that effect, it becomes imperative that strate-
gies are tailored towards minimizing their presence or miti-
gating the adverse effects of monoclinic pyrrhotite. This can
be achieved through selective ore blending, processing of a
selected part of ore grade, or invention of special reagents
that would counteract deleterious effect of monoclinic
pyrrhotite. Overcoming those problems with chalcopyrite
flotation at the source will enable enhancement of efficiency
and general performance of a chalcopyrite flotation process
by the operators.
Despite the optimization of pulp chemistry, the need
for dedicated measures to address the persistent influence
of galvanic interactions is evident. Hence those techniques
that would modify collector formulations or introduce def-
inite additives special for counteraction to galvanic effects
can be considered. Recognition of this prompts a paradigm
shift towards encouraging operators to view galvanic inter-
actions not merely as an inherent by-product but rather as
a controllable variable that can be strategically managed
for improved flotation outcomes. The practical implica-
tions are not confined within theoretical understanding but
extend over a roadmap to implement tangible and targeted
strategies in the field for efficacious and sustainable chalco-
pyrite flotation processes in application aspects.
CONCLUSION
This study offers improved theoretical understanding of the
complex processes influencing chalcopyrite flotation under
various pulp chemistry conditions in the presences of dif-
ferent pyrrhotite superstructures. Based on observations
from different experimental tests evaluating flotation per-
formance, collector adsorption, and electrochemical behav-
iour, the study draws the following conclusions:
1. Optimization of chalcopyrite flotation requires a
detailed understanding of optimum pulp chemis-
try variables such as pH and redox potential, as
minor alterations in these variables show a procliv-
ity to impact performance.
2. Mineralogical characteristics of associated sulphide
minerals (such as pyrrhotite) in pulp played a sig-
nificant role due to variations in the influence of
galvanic interactions as a function of the type of
pyrrhotite superstructure present.
3. Even at the established optimum pulp chemistry
variables (pH and redox potential), the presence
of pyrrhotite negatively impacted chalcopyrite flo-
tation performance, with monoclinic pyrrhotite
being more deleterious than hexagonal pyrrhotite.
4. Both a decrease in pulp chemistry (to pH 9 and
redox potential of –275 mV) and the presence of
monoclinic pyrrhotite induce the greatest reduc-
tion of the noble character of chalcopyrite, ulti-
mately increasing its rate of oxidation.
5. The correlation between flotation performance and
electrochemical behaviour suggests that consider-
ing both pulp chemistry and galvanic interactions