Lead and Zinc Extractive Metallurgy Research …
425
Fig. 9 Kinetic curves for galena leaching
Work started at the University of Idaho and continued at Colorado School of
Mines, evaluated fluosilicic acid leaching of galena [12]. Example results are shown
in Fig. 9. This demonstrated the need for an oxidizing agent to eliminate the effect
of elemental sulfur coating of the particles on the leach kinetics.
Another project carried over from the University of Idaho was the caustic reduction
of galena [13]. The reaction of interest is:
PbS(s) + Na 2 CO 3 (l) + 3/2 O 2 (g) = Pb(l) + Na 2 SO 4 (l) + CO 2 (g)
Experiments were conducted in a crucible furnace at temperatures between 923
and 1133 K. NaCl was added to help in the fluidity and melting point of the slag. This
work is continuing to evaluate methods to regenerate the sodium carbonate from the
slag. The reactor schematic is given in Fig. 10. Example results are given in Fig. 11.
Conclusion
Examples of current and past research on the extractive metallurgy of zinc and lead
performed by graduate students in the Kroll Institute for Extractive Metallurgy have
been presented.
425
Fig. 9 Kinetic curves for galena leaching
Work started at the University of Idaho and continued at Colorado School of
Mines, evaluated fluosilicic acid leaching of galena [12]. Example results are shown
in Fig. 9. This demonstrated the need for an oxidizing agent to eliminate the effect
of elemental sulfur coating of the particles on the leach kinetics.
Another project carried over from the University of Idaho was the caustic reduction
of galena [13]. The reaction of interest is:
PbS(s) + Na 2 CO 3 (l) + 3/2 O 2 (g) = Pb(l) + Na 2 SO 4 (l) + CO 2 (g)
Experiments were conducted in a crucible furnace at temperatures between 923
and 1133 K. NaCl was added to help in the fluidity and melting point of the slag. This
work is continuing to evaluate methods to regenerate the sodium carbonate from the
slag. The reactor schematic is given in Fig. 10. Example results are given in Fig. 11.
Conclusion
Examples of current and past research on the extractive metallurgy of zinc and lead
performed by graduate students in the Kroll Institute for Extractive Metallurgy have
been presented.