U5 Bayer process

What Ore is used to produce Aluminum Oxide?

Bauxite Ore

Define Purification?

Removal of unwanted substances from a material, so that the desired substance has a higher purity.

Where is Bauxite mined from?

Brazil, Australia and Jamaica

What is a Ore?

Rock that has enough useful substance to be worth extracting and economically

Give a example of a Impurity produced in the Bayer Process to ultimately get Aluminium?

Red Mud is a impurity

Why is Red Mud impurity bad for the Bayer process ?

Contaminates Aluminium, affects other stages of Bayer process, increases costs and energy needs, harmful to the environment, large amounts of waste produced.

What are the 4 stages of the Bayer Process to produce Aluminum Oxide?

1. Digestion

2. Filtration

3. Precipitation

4. Calcination

What happens in the Digestion stage for Bayer process?

Bauxite is crushed to small grains, then mixed with hot sodium hydroxide(NaOH) in high temp and pressure. This led’s to Sodium aluminate solution (slurry) to be formed.

What happens in the filtration stage of the Bayer Process?

Flocculants used to help clump impurties together. Sodium aluminate solution is filtered to remove red mud a solid impurity.

What happens in the precipitation stage?

Aluminium hydroxide crystals are added to the solution which forms Aluminium trihydroxide.

What happens in the calcination stage?

The aluminum hydroxide is washed then is heated to remove chemically combined water to produce aluminium oxide.