1. Leaching Reagents H.Naderi, Mining Engineering Department, Yazd University, 2011

2. Leaching Reagents H.Naderi, Mining Engineering Department, Yazd University, 2011

3. Leaching Reagents H.Naderi, Mining Engineering Department, Yazd University, 2011

4. 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

5. Leaching Reagent Properties H.Naderi, Mining Engineering Department, Yazd University, 2011  More Expensive  Negligible Corrosion problems  More Selective: Limestone, dolomite etc do not react

6. Leaching Reagent Properties H.Naderi, Mining Engineering Department, Yazd University, 2011 Insoluble Foaming Acid is consumed Solution contamination with Fe+3

7. 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

8. Water H.Naderi, Mining Engineering Department, Yazd University, 2011

9. Acids H.Naderi, Mining Engineering Department, Yazd University, 2011

10. Acids H.Naderi, Mining Engineering Department, Yazd University, 2011

11. Acids H.Naderi, Mining Engineering Department, Yazd University, 2011 Dilute sulphuric acid Copper oxide ores Zinc Oxide Phosphate rock…

12. Acids H.Naderi, Mining Engineering Department, Yazd University, 2011 Leaching in a sulphuric acid media under oxidasing conditions: Oxygen: Oxidasion Easily Soluble metal sulphate

13. Acids H.Naderi, Mining Engineering Department, Yazd University, 2011 Leaching in a sulphuric acid media under oxidasing conditions: Nitric Acid: Ferric Sulphate:

14. 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:

15. 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:

16. Acids H.Naderi, Mining Engineering Department, Yazd University, 2011 Aqua regia:

17. Bases H.Naderi, Mining Engineering Department, Yazd University, 2011 NaOH:

18. Bases H.Naderi, Mining Engineering Department, Yazd University, 2011 Ammonium hydroxide:

19. Aqueous Salt Solutions H.Naderi, Mining Engineering Department, Yazd University, 2011

20. Aqueous Salt Solutions H.Naderi, Mining Engineering Department, Yazd University, 2011

21. Aqueous Salt Solutions H.Naderi, Mining Engineering Department, Yazd University, 2011

22. Aqueous Salt Solutions H.Naderi, Mining Engineering Department, Yazd University, 2011

23. Aqueous Salt Solutions H.Naderi, Mining Engineering Department, Yazd University, 2011

24. Leaching Reagents H.Naderi, Mining Engineering Department, Yazd University, 2011