Ferronickel preparation using Ni-Fe co-deposition process

Abstract

Nucleation mechanism and technological process for Ni-Fe co-deposition with a relatively high Fe²⁺ concentration surrounded were described, and the effects of Fe²⁺ concentration, solution pH, temperature, and sodium dodecyl sulfonate concentration were investigated. Electrochemical experiments demonstrate that iron’s electrodeposition plays a leading role in the Ni-Fe co-deposition process, and the co-deposition nucleation mechanism accords with a progressive nucleation. Temperature increase does favor in increasing nickel content in the ferronickel (Ni-Fe co-deposition products), while Fe²⁺ concentration increase does not. When solution pH is higher than 3.5, nickel content in the ferronickel decreases with pH because of the hydrolysis of Fe²⁺. With the current density of 180 A/m², Na₂SO₄ concentration of 100 g/L and Ni²⁺ concentration of 60 g/L, a smooth ferronickel deposit containing 96.21% Ni can be obtained under the conditions of temperature of 60 °C, Fe²⁺ concentration of 0.3 g/L, solution pH of 3 and sodium dodecyl sulfonate concentration of 40 mg/L.