1896 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
the different treatments ranged from 64% to 85% As. The
highest As dissolution was obtained at the maximum sol-
vent concentration, finest particle size (P80 of 37 microns)
and minimum solution temperature. Furthermore, based
on Figure 4, solvent concentration is directly proportional
to arsenic dissolution. Increasing the solvent concentration
indicates that more ClO– ions are available for consump-
tion. This trend agrees with other studies (Mitovski et al.
2015 Curreli et al., 2005).
On the other hand, the increase in temperature to 60°C
decreased the arsenic dissolution. This can be attributed
to the possible accelerated decomposition of hypochlorite
0
2
4
6
8
10
12
14
16
-100
0
100
200
300
400
500
600
700
800
0 10 20 30 40 50 60 70 80 90 100 110 120
Time, mins mV pH
Figure 2. Potential – pH graph of NaClO-NaOH leaching of sample ore with P
80 of 37 um, 0.6M
NaClO and 3.5M NaOH at 30°C
0%
20%
40%
60%
80%
100%
0 10 20 30 40 50 60 70 80 90 100 110 120
Time, mins
Figure 3. Arsenic dissolution graph of NaClO-NaOH leaching of sample ore with P80 of 37 um,
0.6M NaClO and 3.5M NaOH at 30°C
Table 2. Arsenic Dissolution for NaClO-NaOH Leaching Treatments
Treatment Concentration Temperature Particle Size
Ave Arsenic
Dissolution, %
A – – – 70.60
B – – +76.88
C – +– 64.38
D – ++72.25
E +– – 80.38
F +– +85.46
G ++– 73.45
H +++79.40
pH
E,
mV
%Arsenic
Dissolution
the different treatments ranged from 64% to 85% As. The
highest As dissolution was obtained at the maximum sol-
vent concentration, finest particle size (P80 of 37 microns)
and minimum solution temperature. Furthermore, based
on Figure 4, solvent concentration is directly proportional
to arsenic dissolution. Increasing the solvent concentration
indicates that more ClO– ions are available for consump-
tion. This trend agrees with other studies (Mitovski et al.
2015 Curreli et al., 2005).
On the other hand, the increase in temperature to 60°C
decreased the arsenic dissolution. This can be attributed
to the possible accelerated decomposition of hypochlorite
0
2
4
6
8
10
12
14
16
-100
0
100
200
300
400
500
600
700
800
0 10 20 30 40 50 60 70 80 90 100 110 120
Time, mins mV pH
Figure 2. Potential – pH graph of NaClO-NaOH leaching of sample ore with P
80 of 37 um, 0.6M
NaClO and 3.5M NaOH at 30°C
0%
20%
40%
60%
80%
100%
0 10 20 30 40 50 60 70 80 90 100 110 120
Time, mins
Figure 3. Arsenic dissolution graph of NaClO-NaOH leaching of sample ore with P80 of 37 um,
0.6M NaClO and 3.5M NaOH at 30°C
Table 2. Arsenic Dissolution for NaClO-NaOH Leaching Treatments
Treatment Concentration Temperature Particle Size
Ave Arsenic
Dissolution, %
A – – – 70.60
B – – +76.88
C – +– 64.38
D – ++72.25
E +– – 80.38
F +– +85.46
G ++– 73.45
H +++79.40
pH
E,
mV
%Arsenic
Dissolution