What do all of these have in common??

They are all made of copper….

A VERY USEFUL METAL

Lesson Objectives:Describe how to extract copper by smelting (C)Explain why low-grade ores are now being exploited. (C)Explain two methods for extracting copper from low-grade ores. (B-A)Evaluate the different methods of copper extraction (A*)

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ore

Lesson Outcomes:• ‘What do all the images have in

common’ – Starter• Active Listening Task – phytomining and

bioleaching (C-B)• Story board explaining phytomining (A)• Exam style questions (C-A)• Plenary – summaries copper extraction

in one sentence

Context:Earth Scientisits

http://www.youtube.com/watch?v=yKWFvelN1gI

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Active Listening – Phytomining and Bioleaching Summary

High grade ore Smelting (heating) Electrolysis/displacement

- Pollution/damage to the environment- They are running out

Less copper inside the ore (<1%)

Grow the plants on a low grade ore, when it has grown burn the plants and the ashes contain copper which can be extracted by electrolysis

Bacteria

A solution which can go through electrolysis or displacement – to extract the copper

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Active Listening – Phytomining and Bioleaching Summary

Because the copper ions are positively charged so they are attracted to the negative electrode

Because iron is more reactive than copper

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Active Listening – Phytomining and Bioleaching Summary

Problems with traditional mining of copper rich ores:

Produces large amounts of waste rock

Requires lots of energy

Creates large holes in the

Earth’s crust and looks ugly

Only worthwhile extracting from high

grade ores – is expensive

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

• Using plants to extract copper

• Alternative to traditional open cast mining

• Do not have to have a high grade copper ore! (Good because high grade ores are running out…)

Phytomining:Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Create a story board explaining the extraction of copper from phytomining (C-A)

Step 1: Copper

ion

Copper ions in the soil (low grade copper substance)…

… are absorbed by the roots of

the plant

Roots

Soil

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Create a story board explaining the extraction of copper from phytomining (C-A)

Step 2:

Copper ions become part

of the plant…

Copper

ion

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Create a story board explaining the extraction of copper from phytomining (C-A)

Step 3

Plant containing the copper

is burned

This produce

s a waste gas – CO2

It is burned

in oxygen

(O2)

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Create a story board explaining the extraction of copper from phytomining (C-A)

Step 3Coppe

rion

Oxide ion

Copper ions join with oxide ions from

the air during burning reaction

Copper + Oxide Copper ion ion oxideCu2+ + O2- CuO

+Coppe

rion

Oxide ion

Copper

ion

Oxide ion

Copper compound

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Create a story board explaining the extraction of copper from phytomining (C-A)

Step 4Ash containing Copper oxide is dissolved in

sulphuric acid

Once filtered a solution of

Copper Sulphate is produced

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Create a story board explaining the extraction of copper from phytomining (C-A)

Step 5:

Electrolysis of Copper Sulphate solution

Copper metal collects at the

negative electrode

This process is called

electrolysis

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Create a story board explaining the extraction of copper from phytomining (C-A)

• Uses low grade copper ore

• Requires less energy than smelting

• Produces less air pollution

• Reduces amount of waste rock

Advantages:Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Create a story board explaining the extraction of copper from phytomining (C-A)

• Can produce toxic chemicals

• Much slower process

• Electrolysis requires large amounts of electricity - expensive

Disadvantages:Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Outcomes: Create a story board explaining the extraction of copper from phytomining (C-A)

Create a story board outlining the process of Phytomining (C-B)

Extension… What are the advantages and disadvantages

to phytomining?

Feedback…..

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Summary Questions…. Phytomining (12 minutes)

Outcomes: Create a story board explaining the extraction of copper from phytomining (C-A)

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

EconomicalOutcomes: Exam style questions (C-A*)

Feedback… self-assess(12 minutes)

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

EconomicalOutcomes: Exam style questions (C-A*)

Task: Active Reading - BioleachingBioleaching factsheet and questionsBioleaching is the extraction of specific metals from their ores through the use of bacteria. They do this by producing leachate solutions that contain the metal compounds. A leachate is simply the solution we get when a liquid passes through an organism. It can therefore be used to extract copper from its ore in a relatively clean process. Bacteria are usually used in the process. Bioleaching is very economical as it is very simple. This makes it quite a cheap process. It is also environmentally friendly, unlike traditional methods of extracting copper, where several damaging gases such as carbon dioxide and sulphur dioxide are produced during smelting. Bioleaching can be used on ores that are poor in quality (otherwise known as low grade ores). This is important because high grade ores are limited in their availability. The process does have some problems however. The process is very slow compared to smelting. There are also some toxic chemicals produced which are harmful to the environment. Also, the efficiency by which the bacteria convert the copper ore into copper metal is very low, so there is a lot of waste.

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

EconomicalOutcomes: Active Reading - bioleaching

Questions• What is bioleaching? (2 marks)   • Describe what the leachate is and how it is

formed (including the type of organism involved)? (3 marks)

 

  Higher• Evaluate bioleaching. Give three advantages of

bioleaching and three disadvantages of bioleaching (6 marks)

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

EconomicalOutcomes: Active Reading - bioleaching

Mark scheme for bioleaching questions• The extraction of specific metals from their

ores (1 mark) using bacteria (1 mark)• Leachate is the solution that contains the

copper compound (1 mark). It is produced by bacteria (1 mark) and is formed when a liquid passes through an organism (1 mark)

• Advantages (any three of the following):• It is a simple process• It is a cheap process• We can use low grade ores• It is environmentally friendly/fewer waste gases

produced (3 marks)

• Disadvantages:• It is a slow process• Toxic chemicals are produced• It has low efficiency (3 marks)

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

EconomicalOutcomes: Active Reading - bioleaching

Bioleaching

Key Words:

Smelting

Extracting

Electrolysis

Bioleaching

Phytomining

Displace

Native Metal

Low-grade ores

High-grade ores

Economical

Plenary:Write ONE sentence to include the following

copper extracting methods:

- Smelting- Bioleaching- phytomining

Outcomes: Summary Plenary