Table 2 Summary of leaching methods

From: Sustainable extraction of rare earth elements from coal fly ash leachates using a recyclable ionic liquid

Leachate type

Liquid: solid ratio (mL/g)

Temperature (°C)

Duration (h)

Reference

12 M HCl

10

85

4

59

15 M HNO3

20

85

4

18

2 M H2SO4

100

80

2

60

0.1 M sodium citrate (pH = 2)

200

25

4

65

Back to article page