TY - JOUR
T1 - A kinetic model to describe the nickel electro-recovery from industrial plating effluents under variable electrolyte conductivity
AU - Hernández-Tapia, J. R.
AU - Vazquez-Arenas, J.
AU - González, I.
N1 - Funding Information:
The authors are indebted to the CONACyT (Mexico) for their financial support to carry out this work, and for the fellowship granted to JRHT to pursue Ph.D. studies.
PY - 2013
Y1 - 2013
N2 - A comprehensive model is developed to account for the kinetics of nickel electro-recovery from industrial plating effluents, typically containing low sulfate (1.25-18.73 mol m-3), chloride (0.49-7.41 mol m-3) and borates concentrations (9.96-150 mol m-3) at pH 4. The model is developed for linear sweep voltammetry considering the mass-transport of six species in solution under stagnant conditions: Ni2+, NiSO 4(aq), H+, Na+, SO4 2- and Cl-, and accounting for the kinetic discharges of Ni2+, NiSO4(aq), H+ and H2O on the substrate. Additionally, the challenges imposed for the analysis of different baths with variable electrolyte conductivities (397-4202 μS cm-1), migration effects and diffusion coefficients depending on ionic strength (Nernst-Hartley equation), are incorporated into the model to simulate the real conditions of the plating effluents. When only one nickel species (Ni2+) is considered in the model, large deviations are observed between the model and the experimental data at intermediate and high overpotentials of the voltammograms. On the other hand, very good fits are obtained when two nickel species (Ni 2+, NiSO4(aq)) are introduced in the model for the experiments conducted at variable electrolyte conductivity. The prediction capabilities of the model are clearly proven by simulating different experimental data generated at constant conductivities, using a single set of kinetic parameters calculated from the fitting stage. The model is developed in a general form such that it can be extended for the robust analysis of other systems or experimental conditions.
AB - A comprehensive model is developed to account for the kinetics of nickel electro-recovery from industrial plating effluents, typically containing low sulfate (1.25-18.73 mol m-3), chloride (0.49-7.41 mol m-3) and borates concentrations (9.96-150 mol m-3) at pH 4. The model is developed for linear sweep voltammetry considering the mass-transport of six species in solution under stagnant conditions: Ni2+, NiSO 4(aq), H+, Na+, SO4 2- and Cl-, and accounting for the kinetic discharges of Ni2+, NiSO4(aq), H+ and H2O on the substrate. Additionally, the challenges imposed for the analysis of different baths with variable electrolyte conductivities (397-4202 μS cm-1), migration effects and diffusion coefficients depending on ionic strength (Nernst-Hartley equation), are incorporated into the model to simulate the real conditions of the plating effluents. When only one nickel species (Ni2+) is considered in the model, large deviations are observed between the model and the experimental data at intermediate and high overpotentials of the voltammograms. On the other hand, very good fits are obtained when two nickel species (Ni 2+, NiSO4(aq)) are introduced in the model for the experiments conducted at variable electrolyte conductivity. The prediction capabilities of the model are clearly proven by simulating different experimental data generated at constant conductivities, using a single set of kinetic parameters calculated from the fitting stage. The model is developed in a general form such that it can be extended for the robust analysis of other systems or experimental conditions.
KW - Electrolyte conductivity
KW - Kinetics
KW - Mass-transport
KW - Modeling
KW - Nickel electrodeposition
KW - Recovery
UR - http://www.scopus.com/inward/record.url?scp=84879057322&partnerID=8YFLogxK
U2 - 10.1016/j.electacta.2013.04.122
DO - 10.1016/j.electacta.2013.04.122
M3 - Comentario/Debate
AN - SCOPUS:84879057322
SN - 0013-4686
VL - 103
SP - 266
EP - 274
JO - Electrochimica Acta
JF - Electrochimica Acta
ER -