Question

briefly describe the steps through which Al2O3 can be converted into Al​

Answer 1

The conversion of alumina to aluminum is carried out via a smelting method known as the Hall-Heroult Process. This process takes place at temperatures between 940-980º C and yields an aluminum of high purity

Answer 2

"Answer:

Al2O3 is first obtained by leaching of bauxite ore.

Al2O3.2H2O + 2NaOH ----> 2NaAlO2 + 3H2O

NaAlO2 + H2O ------> Al(OH)3 + NaOH

2Al(OH)3 ---1200 degree C---> Al2O3 + 3H2O

Hall's process is used here:

A mixture of 3-5% Al2O3, 3-8% CaF2 (Flux) , 80-85% of cryolite , Na3AlF6 ( main electrolyte) and 3-8 % of AlF3 is electrolysed using steel cathode lined with carbon and graphite anode.

Molten Aluminium is tapped from the bottom of the chamber.

Reactions are

Cathode:

Al3+(melt) +  3e- ---> Al(liquid)

Anode:

C(s) + O2-(melt) ----> CO(g) + 2e-

C(s) + 2O2- (melt) ----> CO2 + 4e-

Overall Reaction:

2Al2O3 + 3C ----> 4Al + 3CO2

"