Laterite Leach Tests

ANSTO Minerals Report C1206 to Lagoon Creek Resources – Westmoreland Deposits
Residue Grade (ppm U 3O 8)
Residue Grade (ppm U 3O 8)
350
300
250
200
150
100
50
0
500
400
300
200
100
0
5 10 15 20 25
Acid Addition (kg/t)
Junnagunna pH 1.3 Junnagunna pH 1.5 Junnagunna pH 1.7 Junnagunna pH 2.0
5 7 9 11 13 15 17 19 21
Acid Addition (kg/t)
Redtree pH 1.3 Redtree pH 1.5 Redtree pH 1.7 Redtree pH 2.0
FIGURE 4.5 Residue Grade as a Function of pH - Junnagunna and Redtree
Ores (40 °C, 500 mV)
(ii) Effect of Temperature
The effect of leaching temperature is shown in Figure 4.6 for Junnagunna and Figure 4.7 for
Redtree. These tests were carried out under similar base case conditions with temperature as
the only variable. As expected, the uranium leaching rate increased with increasing
temperatures from 30 °C to 50 °C. For both ores, leaching at 30 °C significantly decreased the
25