Schoeman, LiezlNsiengani, Emmanuel NsandaSole, Kathryn C.Sandenbergh, Roelf2020-12-042020-06Schoeman, L., Nsiengani, E.N., Sole, K.C. et al. 2020, 'Effect of aluminium on polarisation parameters and deposit characteristics in typical nickel sulfate electrolyte for electrowinning applications', Hydrometallurgy, vol. 194, art. 105332, pp. 1-9.0304-386X (print)1879-1158 (online)10.1016/j.hydromet.2020.105332http://hdl.handle.net/2263/77286Impurities present in the sulfate electrolyte during nickel electrodeposition influence the electrowinning process and morphology of deposited nickel metal in various ways. The presence of aluminium can be either detrimental or beneficial, depending on its concentration. Effects of the presence of aluminium in the electrolyte during nickel electrowinning were investigated by evaluation of the relationship between nucleation and plating overpotentials, nickel morphology, deposit contamination, internal stress development, and buffer characteristics of the electrolyte. Results showed that aluminium present at concentrations of lower than 1250 mg/L was unfavourable for the electrowinning process and highly strained nickel deposits of poor morphology were produced; at higher concentrations, the presence of aluminium was advantageous for the morphology and internal stress, and correlated with increased buffer characteristics of the electrolyte.en© 2020 Elsevier B.V. All rights reserved. Notice : this is the author’s version of a work that was accepted for publication in Hydrometallurgy. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. A definitive version was subsequently published in Hydrometallurgy, vol. 194, art. 105332, pp. 1-9, 2020, doi : 10.1016/j.hydromet.2020.105332.Nickel electrowinningAluminium impurityDeposit morphologyNucleation overpotentialPlating overpotentialGalvanodynamic polarisationInternal stressEngineering, built environment and information technology articles SDG-06SDG-06: Clean water and sanitationEngineering, built environment and information technology articles SDG-08SDG-08: Decent work and economic growthEngineering, built environment and information technology articles SDG-09SDG-09: Industry, innovation and infrastructureEngineering, built environment and information technology articles SDG-12SDG-12: Responsible consumption and productionEngineering, built environment and information technology articles SDG-13SDG-13: Climate actionPostprint Article