Question

What is the Chemical reagent used in leaching of bauxite

Answer 1

Sodium Hydroxide is mainly used for leaching of bauxite in Aluminum production.

Answer 2

Answer: NaOH

Explanation: Leaching is the process of treating powdered ore with a suitable reagent which can selectively dissolves the ore and leave the impurities .

Alumina is obtained from bauxite by leaching with NaOH.

$Al_2O_3(s)+2NaOH(aq)+3H_2O(l)\rightarrow 2Na[Al(OH)_4](aq)$

$SiO_2(s)+2NaOH(aq)\rightarrow Na_2SiO_3(aq)+H_2O(l)$

$2Na[Al(OH)_4](aq)+2CO_2(g)\rightarrow Al_2O_3.xH_2O(s)+2NaHCO_3(aq)$

$Al_2O_3.xH_2O(s)\rightarrow Al_2O_3(s)+xH_2O9g)$