1. Production of Pb - bluish-white color when freshly cut
- 11,34g/cm3, melting point 327°C (10,69g/cm3)
- boiling point 1740°C (vaporizes at 550°C)
- bad heat and electrical conductor
- very soft, highly malleable

2. - výroba plášťů zemních kabelů
Usage
- výroba plášťů zemních kabelů
- radiation shields
- bullets and shot
- lead-acid batteries
- alloys: PbSb, solder - PbSn,antifriction alloy - PbSnSb- compounds: carbonate, oxides

3. - galena is the most important and widely used
Occurance
only in compounds
galena - PbS
cerussite - PbCO3
anglesite– PbSO4
- galena is the most important and widely used
- the main impurities: Cu, Zn, Sb, Fe, As, Sn, Ag, Bi
a big amount of gangue

4. - selective&collective (PbZn) concentrate: 40-70% Pb
Occurance
only in compounds
galena - PbS
cerussite - PbCO3
anglesite– PbSO4
- selective&collective (PbZn) concentrate: 40-70% Pb
- other source(40%): waste batteries etc.

5. Production
Pb is produced mainly by pyro. way
- Reduction smelting: 90%
- ISP: 5 %
- Others: 5%

6. Production of Pb Reduction smelting
Roasting:removal of S, conversion of sulphide into oxide
Sintering: coarsening agllomerate
Reduction smelting
Purification of lead bullion

7. - Done together on a (Dwight-Lloyd)sintering machine
Roasting and sintering
- Done together on a (Dwight-Lloyd)sintering machine
- providing Pb content under 2% (mixing raw concentrate with returned agglomerate)
- partial removal of Sn and Sb as As2O3 a Sb2O3

8. Reduction smelting in lead blast furnace
Obtain as much as possible lead bullion
Dissolve as much as possible noble metals in Pb
Move all gangue and Zn into slag
Separate Cu off Pb in form of matte

9. Reduction smelting in lead blast furnace
1. zone: under 400°C, drying and warming of charge .2. zone (reduction): °C, removal of water, decomposition of carbonate & sulfate, reduction of oxides, sulfidization of Cu3. zone (melting): above 900°C, streaming down liquid Pb to crucible, dissolution of Au, Ag, Cu, As, Sb, Sn etc. into lead bullion

10. - charge: coke, air, sinter, CaO
Reduction smelting in lead blast furnace
- charge: coke, air, sinter, CaO
PbO + CO = Pb + CO2PbO.SiO2 + CaO = PbO + CaO.SiO2PbO.Fe2O3 = PbO + Fe2O3PbSO4 = PbO + SO3PbS +2PbO = 3Pb + SO2PbSO4 + 4 CO = PbS + 4 CO2PbSO4 + Pb = 2PbO + SO2PbSO4 + SiO2 = PbO.SiO2 + SO3
Main reactions

11. Reduction smelting in lead blast furnace

12. Construction of the furnace
Reduction smelting in lead blast furnace
continuous taping, the principle of connected vessels
Construction of the furnace

13. Products of reduction smelting
- lead bullion90-96% Pb, 0,2-2,5% Cu, 0,5-5% Sb, 0,1-0,8% As, 0,1-1,5% Sn, 0,06-0,5% Ag
- slag % SiO2, % FeO, % CaO, 5 - 8% Al2O3 + MgO, Pb, ZnO ( 30%)
- BF gas
CO, CO2, SO2, vapor, N2, dust (3-50 g/m3, 40-80% Pb, toxic)

14. Refining of lead bullion
- removal of dross and Cu- removal of As, Sn, Sb,- removal (recovery) of noble metals- removal of Bi

15. Refining of lead bullion
removal of dross:
- stirring at 500°C
- physical impurities ascending to the surface of lead melt (difference in specific gravity)
- withdrawing as dross

16. Refining of lead bullion
removal of Cu:
- limited dissolution of Cu v Pb at low temp., higher affinity of Cu to S than that of Pb
- 1. step:
lowering or increasing temperature of the melt just above of melting point of Pb
- 2. step (350°C): adding elemental S to form Cu2S (under 0,002%)

17. Refining of lead bullion
removal of Sn, As, a Sb
- higher affinity with oxygen, comparing to Pb
- oxidation with air or with sodium nitrate
- oxidation with air:
500°C to remove Sn, 700°C-800°C to remove As, Sb

18. Refining of lead bullion
removal of Sn, As, a Sb
- oxidation with sodium nitrate (Harris’ refining) fused sodium hydroxide, 500°C
+ oxides As, Sb, Sn have acidic character, reaction with oxides of alkli metals to form arsenate, antimonate (V), stannate

19. Refining of lead bullion
removal of Sn, As, a Sb
- oxidation with sodium nitrate (Harris refining) NaNO3 = Na2O +2.5 O2 + N As O2 =AsO Sn + O2 = SnO Sb O2 = Sb2O As2O5 + 3Na2O = 2Na3AsO Sb2O5 + 3Na2O = 2Na3SbO SnO2 + Na2O = Na2SnO3     

20. Refining of lead bullion
recovery of noble metals (Parkes’ method)
- de-silvering lead by adding metal Zn to form inter- metallic compound (higher melting point, lower specific gravity)
- 500C, stirring, cooling almost to consolidation, formation of foam containing noble metals (Ag, Au..)
- removal of Zn by vacuum

21. Refining of lead bullion
removal of Bi
atd1.) Kroll-Betterr’s method (under1%Bi)
- adding Pb-Ca (3- 4% Ca) and Mg metal
- slow cooling from 400°C to 360°C, foam forming
atd2.) electrolytic refining (Bi >1%)
- electrolyte : PbSiF6 + H2SiF (fluorosilicate and fluorosilic acid)
- Pb cathodes
- Bi and noble metals report into do anode slugde