University of Zimbabwe Publications

DOI: 10.5897/UJ-JASSA

New sampling method on nickel sheet-cathodes, manufactured by the Outokompu process

DOI: 10.5897/UJ-JASSA.17.004.2   |   Article Number: 1E4A933A4   |   Vol.22 (2) - December 2016

Authors:  Wakandigara A. , Mafodya J. and Musarandoga S.

Keywords: Nickel sheet-cathode, Distribution pattern, Sampling method

Obtaining a representative sample from electrometallurgically- generated nickel sheet-cathodes, to determine concentrations of trace elements, has always been a challenge, due to the heterogeneous distribution of such impurities in the sheet. Knowledge about the distribution patterns of impurities in the nickel cathodes is scanty and studies concerning appropriate sampling methods for nickel sheet-cathodes are not extensive. 
An investigation was done on the distribution patterns of cobalt, copper, iron and zinc in nickel cathodes and various sampling methods were tested on an isolated-and-profiled nickel cathode. It was observed that the distribution of the four above-mentioned impurities did not follow a consistent pattern and in all cases random sampling produced more accurate results than the current sampling methods. A new random-based sampling technique was then designed. 

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