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Leaching Reagents
H.Naderi, Mining Engineering Department, Yazd University, 2011
Leaching Reagents
H.Naderi, Mining Engineering Department, Yazd University, 2011
Leaching Reagents
H.Naderi, Mining Engineering Department, Yazd University, 2011
Leaching Reagents
Leaching is usually carried out in Water solutions
Often: Addition of other leaching reagents is required
H.Naderi, Mining Engineering Department, Yazd University, 2011
Acids
Bases
Sulphides
Salts
Combination of these
Leaching Reagent Properties
H.Naderi, Mining Engineering Department, Yazd University, 2011
More ExpensiveNegligible Corrosion problemsMore Selective: Limestone, dolomite etc do not react
Leaching Reagent Properties
H.Naderi, Mining Engineering Department, Yazd University, 2011
Insoluble
Foaming
Acid is consumedSolution contamination with Fe+3
Water
• Water alone maybe used for the leaching of roasted
materials such as sulphates and chlorides.
• In the presence of oxygen, some sulphides may be
leached by means of water under pressure and at
temperatures above 150-200 $ C
H.Naderi, Mining Engineering Department, Yazd University, 2011
Water
H.Naderi, Mining Engineering Department, Yazd University, 2011
Acids
H.Naderi, Mining Engineering Department, Yazd University, 2011
Acids
H.Naderi, Mining Engineering Department, Yazd University, 2011
Acids
H.Naderi, Mining Engineering Department, Yazd University, 2011
Dilute sulphuric acid
•Copper oxide ores
• Zinc Oxide
• Phosphate rock…
Acids
H.Naderi, Mining Engineering Department, Yazd University, 2011
Leaching in a sulphuric acid media under oxidasing
conditions:
Oxygen:
Oxidasion
Easily Soluble metal sulphate
Acids
H.Naderi, Mining Engineering Department, Yazd University, 2011
Leaching in a sulphuric acid media under oxidasing
conditions:
Nitric Acid:
Ferric Sulphate:
Acids
H.Naderi, Mining Engineering Department, Yazd University, 2011
HCl has replaced sulfuric acid in many reactions involving iron oxid:
Leaching of ilmenite
Nitric Acid:
Acids
H.Naderi, Mining Engineering Department, Yazd University, 2011
•The use of nitric acid is limited
•Displacing H2SO4 in some uranium extraction operations: Solve
radium gases problems
Solubilize sulphide minerals:
Acids
H.Naderi, Mining Engineering Department, Yazd University, 2011
Aqua regia:
Bases
H.Naderi, Mining Engineering Department, Yazd University, 2011
NaOH:
Bases
H.Naderi, Mining Engineering Department, Yazd University, 2011
Ammonium hydroxide:
Aqueous Salt Solutions
H.Naderi, Mining Engineering Department, Yazd University, 2011
Aqueous Salt Solutions
H.Naderi, Mining Engineering Department, Yazd University, 2011
Aqueous Salt Solutions
H.Naderi, Mining Engineering Department, Yazd University, 2011
Aqueous Salt Solutions
H.Naderi, Mining Engineering Department, Yazd University, 2011
Aqueous Salt Solutions
H.Naderi, Mining Engineering Department, Yazd University, 2011
Leaching Reagents
H.Naderi, Mining Engineering Department, Yazd University, 2011
