| The overall objective of this thesis was to study glue, Tembind, thiourea, chloride and reclaimed acid, and determine how their presence (in typical industrial concentrations), alone and in combination, in synthetic electrolyte affects the cathodic overpotential and copper cathode deposit morphology. It was hoped that a solution could be found to permit an increase in copper cathode production at the tankhouse by employing higher current density. The first part of the thesis gives an overview of copper electrorefining, its theoretical fundamentals as well as its practical use in industry. The experimental part of the thesis consists of three major sections: laboratory electrorefining tests, cathodic polarization tests and reclaimed acid characterization.; The laboratory electrorefining tests were done using laboratory scale electrorefining cells that could simulate the CCCR electrorefining operation. The lab scale cathode deposits were judged by naked eye observation, by microscopy of polished cathode sections, and by hardness measurements. Microscopic evaluation of deposits clarified the macroscopic interpretation and highlighted differences, between the deposits, that were not evident to the naked eye. (Abstract shortened by UMI.)... |
