The document describes the process of refining copper from its ore. There are several key steps:
1) Mining the copper ore from underground deposits. 2) Crushing and grinding the ore to liberate copper particles from waste rock. 3) Concentrating the ore using froth flotation to separate copper minerals from waste gangue. 4) Extracting copper through roasting to form copper oxide and smelting to produce copper matte and remove iron. 5) Further refining copper using bessemerization and electrorefining or distillation to produce high purity copper.
1. Click to edit Master title style
1
CHEMICAL INDUSTRIES
2. Click to edit Master title style
2
REFINING OF COPPER
To use copper we separate it from its ore because
in nature it is found as copper ores. This process
of separation of copper from its ore is called
Metallurgy.
3. Click to edit Master title style
3
STEPS IN METALLURGY
• Mining of ore
• Crushing and grinding of ore
• Concentration of ore
• Extraction of metal
• Refining of metal
4. Click to edit Master title style
4
MINING OF ORE
Copper ores are found underground. They
are taken out by mining for further
purification of ore and extraction of copper
metal from copper pyrite and copper glance.
5. Click to edit Master title style
5
CRUSHING AND GRINIDING OF ORE
The ores mined from the ground are
mechanically crushed and ground. It is done
to liberate valuable mineral (copper) from
the waste (gangue) mineral.
6. Click to edit Master title style
6
CONCENTRATION OF ORE
Most copper ores contain only a small
percentage of copper metal bound up within
valuable ore mineral, with the remainder of
the ore being unwanted rock or gangue
mineral
7. Click to edit Master title style
7
CONCENTRATION OF ORE
• Froth floatation:
Froth floatation is used to physically
separate ore from gangue. This process is used for the
separation of a large range of sulphides, carbonates, and
oxides for further refinement
8. Click to edit Master title style
8
EXTRACTION OF METAL
After the separation of ore and gangue by froth
flotation some chemical processes are done to
extract metals. These chemical processes are
roasting and smelting.
9. Click to edit Master title style
9
ROASTING
• Definition:
The process in which minerals are
converted into oxides by heating in the air below
their melting point is roasting.
• Chemical equation:
2 CuFeS2 + 3 O2 → 2 FeO + 2 CuS + 2 SO2
10. Click to edit Master title style
1
0
SMELTING
• The method to reduce metal ions to free metals is
called smelting
• Smelting of copper ore is done in two steps i.e.
formation of copper matte and bessemerization.
11. Click to edit Master title style
11
FORMATION OF COPPER MATTE
The roasted copper ore is heated with coke and
sand at about 1100ºC. The materials melt and
separate into two layers. The bottom layer that
contains mixtures of Cu2S and FeS is called
matte. While upper layer is called silicate slag.
FeO + SiO2 → FeO.SiO2
2 FeS + 3 O2 → 2 FeO + 2 SO2
12. Click to edit Master title style
1
2
BESSERMERIZATION
In this process air is blown through the copper
matte in the Bessemer converter. Remaining iron
sulphide is oxidized and removed as slag. In the
final smelting step cuprous sulphide is oxidized to
form cuprous oxide, which react with remaining
cuprous sulphide to form metallic copper.
Cu2S+O2→2Cu+SO2
13. Click to edit Master title style
13
REFINING OF METAL
• The metal obtained from smelting contains
impurities, that can be refined by electro refining
or distillation.
14. Click to edit Master title style
1
4
• An electrolytic cell is used in electro refining, in
which impure metal act as anode and a sample of
pure metal acts as cathode.
• At the anode: Cu(s) → Cu2+
(aq) + 2e−
• At the cathode: Cu2+
(aq) + 2e− → Cu(s)