3144 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
between galena and pyrite further decreased. The decrease
of galvanic interaction between galena and pyrite could
be caused by the absorption of NaHA on the mineral sur-
face, which weakened the electron transfer effect of contact
between minerals.
Adsorption Model and Depression Mechanism
Based on the above results, Figure 14 shown the adsorption
mechanism of reagents on the surface of galena and pyrite.
Galena and pyrite had good floatability without depressant.
In the presence of combined depressants, more Ca2+ were
absorbed on the surface of pyrite and the adsorption of
NaHA on pyrite surface was promoted. The adsorption of
NaHA on the surface of mineral could weaken the electron
transfer between galena and pyrite, and then reduce the gal-
vanic interaction between galena and pyrite. After interac-
tion with the combined depressants, the collector could be
adsorbed on the galena surface but the combined depres-
sants hindered the adsorption of the collector on the pyrite
surface. Therefore, combined depressants could effectively
separate galena from pyrite under low alkali conditions.
CONCLUSIONS
CaCl2 and NaHA as combined depressants in the separa-
tion of galena and pyrite and the mechanism were studied
systematically. Micro-flotation results showed that galena
and pyrite could be separated effectively when CaCl2 and
NaHA were used as combination depressants in the pH
range 6~10. The recovery difference of more than 60%
between the galena and pyrite when the CaCl2 concentra-
tion was 4mg/L and NaHA concentration was 50mg/L.
Zeta potential, contact angle and Raman spectroscopy
measurement demonstrated that combined depressants
adsorbed more on pyrite surface compared with galena and
the combined depressants hindered the adsorption of the
collector on the pyrite surface. While that of the galena
adsorbed significant amount of collector even with CaCl2
and NaHA. Adsorption test demonstrated that more Ca2+
were absorbed on the surface of pyrite compared with
galena and Ca2+ could react with NaHA in the solution to
form the complexes, thus improving the depression effect of
NaHA. The electrochemical test illustrated that the adsorp-
tion of NaHA on the surface of mineral could weaken
Figure 14. Schematic of the reagents adsorbed on the surface of galena and pyrite
between galena and pyrite further decreased. The decrease
of galvanic interaction between galena and pyrite could
be caused by the absorption of NaHA on the mineral sur-
face, which weakened the electron transfer effect of contact
between minerals.
Adsorption Model and Depression Mechanism
Based on the above results, Figure 14 shown the adsorption
mechanism of reagents on the surface of galena and pyrite.
Galena and pyrite had good floatability without depressant.
In the presence of combined depressants, more Ca2+ were
absorbed on the surface of pyrite and the adsorption of
NaHA on pyrite surface was promoted. The adsorption of
NaHA on the surface of mineral could weaken the electron
transfer between galena and pyrite, and then reduce the gal-
vanic interaction between galena and pyrite. After interac-
tion with the combined depressants, the collector could be
adsorbed on the galena surface but the combined depres-
sants hindered the adsorption of the collector on the pyrite
surface. Therefore, combined depressants could effectively
separate galena from pyrite under low alkali conditions.
CONCLUSIONS
CaCl2 and NaHA as combined depressants in the separa-
tion of galena and pyrite and the mechanism were studied
systematically. Micro-flotation results showed that galena
and pyrite could be separated effectively when CaCl2 and
NaHA were used as combination depressants in the pH
range 6~10. The recovery difference of more than 60%
between the galena and pyrite when the CaCl2 concentra-
tion was 4mg/L and NaHA concentration was 50mg/L.
Zeta potential, contact angle and Raman spectroscopy
measurement demonstrated that combined depressants
adsorbed more on pyrite surface compared with galena and
the combined depressants hindered the adsorption of the
collector on the pyrite surface. While that of the galena
adsorbed significant amount of collector even with CaCl2
and NaHA. Adsorption test demonstrated that more Ca2+
were absorbed on the surface of pyrite compared with
galena and Ca2+ could react with NaHA in the solution to
form the complexes, thus improving the depression effect of
NaHA. The electrochemical test illustrated that the adsorp-
tion of NaHA on the surface of mineral could weaken
Figure 14. Schematic of the reagents adsorbed on the surface of galena and pyrite