Answer to Question #74561 in Inorganic Chemistry for srikant behera

Question

In which cases is hydrometallurgy applicable? In such cases, how are the leached out
metals recovered from solution? Explain with suitable examples.

Answer 1

Hydrometallurgy is used in cases where the ore you want to extract can go into a soluble form. For example, bauxite containing aluminum can be washed with alkalis

Al2O3 + 6NaOH + 3H2O = 2Na3Al(OH)6

The solution is then acidified and the alumina

2Na3Al (OH) 6 + 6HCl = 6NaCl + Al2O3 + 6H2O
The alumina is then dissolved in cryolite (Na3AlF6) and electrolysis of the melt is carried out