Question

purification of aluminium

Answer 1

 it is extracted by electrolysis. The ore is first converted into pure aluminium oxide by the Bayer Process, and this is then electrolysed in solution in molten cryolite - another aluminium compound. The aluminium oxide has too high a melting point to electrolyse on its own. The usual aluminium ore is bauxite.

Answer 2

For the purification of aluminium, Bayer's Process is used which is main industrial means of refining bauxite to get aluminium.