Journal of Applied Electrochemistry, Vol.31, No.3, 301-305, 2001
Effect of organic extractants on the electrocrystallization of nickel from aqueous sulphate solutions
The effect of the presence of commercial organic extractants LIX 84I, Cyanex 272, D2EHPA, Versatic 10 and TBP with or without Mg2+ on various electrodeposition parameters for nickel deposition on stainless steel cathode from aqueous sulphate solutions was investigated. The parameters included cathodic current efficiency, deposit morphology, crystal orientation and cathodic polarization. There was no significant variation in the current efficiency in the presence of these additives, but changes were observed in the deposit morphologies and crystal orientations even though all the deposits were bright, smooth and coherent. Changes were also observed in the cathodic polarization behaviour during nickel electrocrystallization in the presence of these additives. The effect of the additives on the electrokinetic parameter, exchange current density (i(0)) has also been investigated.
Keywords:current efficiency;electrocrystallization;exchange current density;nickel;nucleation overpotential;organic extractants