Electrochemical Extraction of Pb and Zn from Raw Mineral …
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pH
τ, min
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0,5M NaOH
T = 25˚C; Current density i = 100 A / m2; S: L (1:10); cathode - SGE; anode - graphite;
Fig. 3 Change in pH of solutions in the process of leaching of the concentrate depending on the
concentration
T = 25˚C; Current density i = 100 A / m2; S:L (1:10); cathode - SGE; anode - graphite;
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EhmS/cm
τ, min
0,1M NaOH
0,5M NaOH
Fig. 4 Change in the electrical conductivity of solutions in the process of leaching of the concentrate
depending on the concentration of NaOH
It is shown that the features of leaching solutions can lead to the reverse deposition
of metals in the precipitate.
Figure 5 shows the change in oxygen concentration in the solution during leaching.
It can be assumed that an increase in the concentration of sodium hydroxide in the
initial solution prevents the oxidation of the metal, which precedes the conversion
of the metal into the solution. A change in the oxygen concentration in the leaching