2180 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
that by increasing the pH (and also the ionic strength of
the solution), their long chains partially wrap around them-
selves and, in this way, they have less interaction with the
chalcopyrite particles, reducing their depressant effect.
Induction Time Measurement
Induction time can be used as an indirect measurement of
the hydrophobicity of solid particles. High values indicate
lower hydrophobicity. Therefore, the low recoveries of chal-
copyrite could be correlated with long induction times.
Figures 4, 5 and 6 show the induction time of chalcopyrite
as a function of the dosage of PAM present in the flotation
process for the different flocculant degradation conditions
at pH 7, 9 and 11, respectively. In all of them it is possible
to establish a direct correlation between the induction time
0
10
20
30
40
50
60
70
80
90
100
0 1 2 3 4 5 6 7 8 9 10 11
PAM concentration, mg/L
NS-PAM
MS-PAM
SS-PAM
Figure 1. Chalcopyrite recovery as a function of PAM concentration for the different levels of
mechanical degradation evaluated (NS, MS and SS-PAM) at pH 7 using a 0.01 M NaCl solution
0
10
20
30
40
50
60
70
80
90
100
0 1 2 3 4 5 6 7 8 9 10 11
PAM concentration, mg/L
NS-PAM
MS-PAM
SS-PAM
Figure 2. Chalcopyrite recovery as a function of PAM concentration for the different levels of
mechanical degradation evaluated (NS, MS and SS-PAM) at pH 9 using a 0.01 M NaCl solution
Chalcopyrite
recovery,
%
Chalcopyrite
recovery,
%