Abstract
An examination has been made of the effect of the composition, pH and the temperature of the solution on the deposition of nickel on iron in a fluidized bed that contained iron powder, solution and a fluidizing gas. In certain cases an electric potential was applied to electrodes contained within the bed, but otherwise the deposition process was spontaneous. Three different solutions were studied: nickel chloride, Watt's solution and nickel sulphamate. In the electroless case the highest and lowest deposition rates obtained under a specific set of experimental conditions were associated with the nickel chloride and nickel sulphamate solutions respectively. Even when an electric current was passed through the bed the spontaneous reactions dominated the process. The optimum pH was about 3.6; at other pH values the deposition of nickel was affected adversely by competitive cathodic reactions. The activation energies suggested that the deposition of nickel on iron powder was charge transfer controlled at temperatures below 60° C, but mixed diffusion and charge transfer control were operative at higher temperatures. The morphology of the coating was independent of the experimental conditions used, and always consisted of a nodular deposit giving incomplete coverage of the particles.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Abbreviations
- A :
-
area of deposition surface (m2)
- c :
-
nickel concentration in solution (kg m−3)
- c 0 :
-
initial nickel concentration in solution (kg m−3)
- E o :
-
standard electrode potential (V)
- k :
-
rate constant (m s−1)
- m :
-
slope of Arrhenius plot (K)
- Q :
-
activation energy (J mol−1)
- r :
-
radius of powder particles (m)
- R :
-
gas constant (J mol−1 K−1)
- T :
-
temperature (K)
- V :
-
solution volume (m3)
- A 1 :
-
total surface area of powder (m2)
- A 2 :
-
corrected total surface area of powder (m2)
- h :
-
pit depth (m)
- M t :
-
total mass of coated powder (kg)
- N :
-
number of particles
- N p :
-
number of pits per particle
- r 0 :
-
initial radius of particle (m)
- r 1 :
-
final (uncorrected) radius of particle (m)
- r 2 :
-
final corrected radius of particle (m)
- r p :
-
radius of pits (m)
- V Ni :
-
volume of deposited nickel (m3)
- V 1 :
-
volume of deposited layer (m3)
- Ni :
-
quantity of nickel in coated powder (mass%)
- ρ Ni :
-
density of solid nickel (kg m−3)
References
A. J. Fletcher, S. Jaiswal and R. Cundill, in ‘Modern Perspectives in Powder Metallurgy’, Vol. 12, (edited by H. H. Hausner, H. W. Antes and G. D. Smith) Princeton American Powder Industries Federation, Princeton (1981) p. 177.
J. O'M. Bockris and A. K. N. Reddy, ‘Modern Electrochemistry, Vol. 2, Plenum, New York and London (1970) p. 1267.
I. K. Vetter, ‘Electrochimiques’, Springer, Berlin (1961) p. 610.
V. Annamalai, J. B. Hiskey and L. E. Murr,Hydromet. 3 (1978) 163.
G. P. Power and I. M. Ritchie, in ‘Modern Aspects of Electrochemistry’, Vol. 11 (edited by J. O'M. Bockris and B. E. Conway) Plenum New York and London (1975).
R. S. Rickard and M. C. Furstenau,Trans. Met. Soc. AIME 242 (1968) 1487.
M. E. Wadsworth,ibid. 245 (1969) 1381.
B. J. Sabacky and J. W. Evans,Met. Trans. B,8B (1977) 5.
M. Pourbaix, ‘Atlas de Equilibres Electrochim’ Gauthier-Villars, Paris (1963).
J. D. Miller,Miner. Sci. Eng. 5 (1973) 242.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Cifuentes, L., Fletcher, A.J. Aspects of the deposition of nickel on iron powder in a fluidized bed. J Appl Electrochem 13, 325–335 (1983). https://doi.org/10.1007/BF00941604
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00941604