화학공학소재연구정보센터
Journal of Applied Electrochemistry, Vol.29, No.3, 293-299, 1999
Nickel ferrite as inert anodes in aluminium electrolysis: Part I - Material fabrication and preliminary testing
Dense, sintered samples of nickel ferrite/nickel oxide-copper cermets were produced and characterized. Three compositions were chosen, each with different NiO content. A new method of powder preparation involving no use of water as dispersant resulted in a well-dispersed ceramic phase with smaller metal grains than previously reported. The individual phases in the cermets were analysed quantitatively using energy-dispersive X-ray microanalysis, and significant differences between the materials were found. The electrical conductivity of the materials was measured, showing interesting properties not previously described. Reaction sintering was tried and found to lead to a microstructure different from that obtained with pre-calcined powder. The nickel contamination level in the electrolyte did not reach steady state after 4 h of electrolysis, Iron and copper did seem to reach steady state after some irregular behaviour early in the tests. The total contamination level of anode constituents in the deposited metal was as low as 0.116 wt%. These encouraging results seemed to be partly related to the cell configuration giving very slow mass transfer from the electrolyte into the metal.