1874
Recovery of Nickel and Copper from Nickel Sulfide Flotation
Tailings: Optimization of Effective Parameters
Sabinus Essel Arthur, Emmanuel Atta Mends, Angela Manka Tita,
Shokrullah Hussaini, Pengbo Chu
Department of Mining and Metallurgical Engineering, University of Nevada, Reno, NV, USA
ABSTRACT: This study proposes an efficient approach for the recovery of nickel and copper from nickel sulfide
flotation tailings while establishing the effect of ferric chloride (FeCl3) catalyst on recovery. The effect of four
leaching parameters leaching time, leaching temperature, H2SO4 concentration, and the particle size dependent
on and expressed in terms of the grinding time on recovery of metals was investigated and optimum conditions
using the central composite design (CCD) and response surface methodology (RSM) optimization technique
determined. Preliminary leaching studies indicated that HNO3 acid yielded the best recoveries for nickel under
the same leaching conditions as HCl and H2SO4. However, H2SO4 was selected for practical and economic
justifications. The chloride-based catalyst dosage and leaching temperature were established as the most critical
parameters influencing nickel and copper recovery. The validation leaching tests performed considering the best
process conditions and recoveries from the multiple response optimization for set desirability of 98% recovery
yielded 98.92% and 93.68% recoveries for nickel and 99.14% and 98.72% recoveries for copper. This study
further investigated the kinetics of dissolution, and it was established that the dissolutions of these metals were
internal diffusion controlled with apparent activation energies of 19.17KJ/mol and 15.54KJ/mol for nickel and
copper, respectively.
Keywords: Nickel, Copper, Leaching, Response Surface Methodology, Sulfide Flotation Tailings
INTRODUCTION
In recent years, the growing global population, techno-
logical advancements, and the imperative for sustainabil-
ity have significantly increased the demand for essential
raw materials. The push to phase out fossil fuels, a signifi-
cant contributor to greenhouse gas emissions and climate
change, has heightened demand for minerals (Midilli et
al., 2006). Renewable energy technologies such as wind,
geothermal, solar, biomass, and hydroelectric power offer
environmentally friendly alternatives to meet the escalat-
ing global energy needs. However, the transition to green
energy sources comes with a challenge: the production of
these technologies relies heavily on critical minerals. In
comparison to their fossil-based counterparts, green energy
sources necessitate a greater amount of these minerals.
According to the International Energy Agency (IEA), an
electric vehicle, for instance, requires six times the mineral
inputs of a conventional car, while an offshore wind plant
demands 13 times more mineral resources than a gas-fired
plant of similar size. Current global reserves of critical min-
erals fall short of anticipated future needs to phase out fos-
sils (Karppinen et al., 2024). This underscores the crucial
Recovery of Nickel and Copper from Nickel Sulfide Flotation
Tailings: Optimization of Effective Parameters
Sabinus Essel Arthur, Emmanuel Atta Mends, Angela Manka Tita,
Shokrullah Hussaini, Pengbo Chu
Department of Mining and Metallurgical Engineering, University of Nevada, Reno, NV, USA
ABSTRACT: This study proposes an efficient approach for the recovery of nickel and copper from nickel sulfide
flotation tailings while establishing the effect of ferric chloride (FeCl3) catalyst on recovery. The effect of four
leaching parameters leaching time, leaching temperature, H2SO4 concentration, and the particle size dependent
on and expressed in terms of the grinding time on recovery of metals was investigated and optimum conditions
using the central composite design (CCD) and response surface methodology (RSM) optimization technique
determined. Preliminary leaching studies indicated that HNO3 acid yielded the best recoveries for nickel under
the same leaching conditions as HCl and H2SO4. However, H2SO4 was selected for practical and economic
justifications. The chloride-based catalyst dosage and leaching temperature were established as the most critical
parameters influencing nickel and copper recovery. The validation leaching tests performed considering the best
process conditions and recoveries from the multiple response optimization for set desirability of 98% recovery
yielded 98.92% and 93.68% recoveries for nickel and 99.14% and 98.72% recoveries for copper. This study
further investigated the kinetics of dissolution, and it was established that the dissolutions of these metals were
internal diffusion controlled with apparent activation energies of 19.17KJ/mol and 15.54KJ/mol for nickel and
copper, respectively.
Keywords: Nickel, Copper, Leaching, Response Surface Methodology, Sulfide Flotation Tailings
INTRODUCTION
In recent years, the growing global population, techno-
logical advancements, and the imperative for sustainabil-
ity have significantly increased the demand for essential
raw materials. The push to phase out fossil fuels, a signifi-
cant contributor to greenhouse gas emissions and climate
change, has heightened demand for minerals (Midilli et
al., 2006). Renewable energy technologies such as wind,
geothermal, solar, biomass, and hydroelectric power offer
environmentally friendly alternatives to meet the escalat-
ing global energy needs. However, the transition to green
energy sources comes with a challenge: the production of
these technologies relies heavily on critical minerals. In
comparison to their fossil-based counterparts, green energy
sources necessitate a greater amount of these minerals.
According to the International Energy Agency (IEA), an
electric vehicle, for instance, requires six times the mineral
inputs of a conventional car, while an offshore wind plant
demands 13 times more mineral resources than a gas-fired
plant of similar size. Current global reserves of critical min-
erals fall short of anticipated future needs to phase out fos-
sils (Karppinen et al., 2024). This underscores the crucial