ETD Collection

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Author: search.filters.author.Rodrigues, Jose Carlos Pereira

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    Modelling the performance of Manganese electrowinning cells
    (2015) Rodrigues, Jose Carlos Pereira
    A comprehensive literature survey was conducted to obtain the available information on the manganese electrodeposition process.Using this information and measurments obtained from an industrial electrowinning plant,a modal was developed where the Interrelations between the most important parameters ware taken into account.Fundamental concepts were used wherever possible,except in a small section where no theoretical data was available. In this case empirical fitting of parameters was resorted to. The trends experienced in practice were all confirmed by the mode1,namely$ (i) the increase of cathodic currant efficiency with increased pH,which la limited by the precipitation of manganese hydroxide t (li) the increased current efficiency with decreased ammonium sulphate concentration; (ill) the existence of an optimum operating temperature for a given current density; (iv) the existence of an optimum current density for a given temperature; (v) the effect of total impurity level on current efficiency, the latter decreasing with increasing impurity level (vi) the steep increase of current efficiency with inorease of feed flow rata,to an upper limit condition at which point manganese hydroxide starts precipitating.