Copper from deep in the ground' SL M2'

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Copper from deep in the ground. SL M2.
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Five stages

• Open Pit mining
• Pit crusher 0.6 Cu
• Froth floatation 30 Cu
• Smelting 90.4 Cu
• Electrolytic refining 99.98 Cu

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chalcopyrite
malachite
azurite
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CuFeS2 chalcopyrite. Cu in pure chalcopyrite?
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CuFeS2 Mr 64563232 184
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Open Pit mining.
Bingham Canyon
Low grade copper
Quantities huge
Dynamite used
Shavings tested
Waste to tips
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Open Pit mining.

• Noisy
• Dusty
• Leaves Open Pits
• Waste tips.

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Pit crusher
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Pit crusher
0.6 Cu
2.5cm pieces
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Froth Floatation
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Froth Floatation
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Froth Floatation

• Tailings

0.6
Collector (oil) molecules attach themselves to
the chalcopyrite grains. The grains are now
water-repellent. Air bubbles attract the
grains. Froth produced and is pumped away to
smelter.

• Detergent
• Oil
• Water

30
concentrating
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Smelting

• First stage involves
• Silica
• Oxygen
• Concentrate
• Cu2S made

• Most important stage involves Cu2S / air /
  furnace
• Cu2S(l) O2(g) ? 2Cu(l) SO2(g)

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Oxidised or reduced?
Cu2S O2 ? 2Cu SO2
reduced
Cu
1 0
oxidised
S
-2 4
O
reduced
0 -2
What mass of copper could be obtained by reducing
1kg of copper (I) sulphide?
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What mass of copper could be obtained by reducing
1kg of copper (I) sulphide?
Cu2S O2 ? 2Cu SO2
Underline
1 mol 2 mol
Moles in
160 128
Mass in
Mass in question
1kg
0.800kg
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Smelting
Acid rain
Trees
Sulphur dioxide made.
Lakes
H2SO4
30
99.4
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Electrolytic Refining
99.4
99.98
The copper anodes are already 99.4 copper!
The copper cathodes will be 99.98 copper!
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(No Transcript)
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- Cathode
Anode
Cu2
Cu
Cu2
e-
e-
Cu
Cu
Cu2
Cu
e-
e-
Cu2
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• Describe what is happening at the anode.
• Write an equation.
• Is this oxidation or reduction?

- Cathode
Anode
Cu2
Cu
Cu2
e-
e-
Cu
Cu
Cu2
Cu
e-
e-
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• Describe what is happening at the cathode.
• Write an equation.
• Is this oxidation or reduction?

- Cathode
Anode
Cu2
Cu
Cu2
e-
e-
Cu
Cu
Cu2
Cu
e-
e-
Cu2
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• Write an equation.
• Cu(s) ? Cu2(aq) 2e-
• Is this oxidation or reduction?
• Oxidation

- Cathode
Anode
Cu2
Cu
Cu2
e-
e-
Cu
Cu
Cu2
Cu
e-
e-
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• Write an equation.
• Cu2(aq) 2e- ? Cu(s)
• Is this oxidation or reduction?
• Reduction

- Cathode
Anode
Cu2
Cu
Cu2
e-
e-
Cu
Cu
Cu2
Cu
e-
e-
Cu2
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Five stages

• Open Pit mining
• Pit crusher
• Froth floatation
• Smelting
• Electrolytic refining