Chemical Engineering - Chemical Process - Discussion

The starting raw material for the manufacture of alum is bauxite.

Here's why;

Bauxite: Bauxite is the primary ore of aluminium. It contains aluminium oxide (Al2O3) along with impurities like iron oxide, silica, and titanium oxide.

Alumina (Al2O3): Alumina is produced from bauxite through a process called the Bayer process. Alumina is a key ingredient in the production of alum.

Gypsum (CaSO4·2H2O): Gypsum is used in the alum production process, but it's not the primary raw material. It's added to control the crystallization process and to improve the quality of the alum crystals.

Ammonium Bicarbonate (NH4HCO3): Ammonium bicarbonate is a reagent used in some alum production methods, but it's not a starting material.

The Process:

Bauxite Mining: Bauxite ore is mined from deposits.

Bayer Process: Bauxite is treated with sodium hydroxide (NaOH) to extract alumina (Al2O3).

Alum Production: Alumina is then reacted with sulfuric acid (H2SO4) to produce aluminium sulfate (Al2(SO4)3). This is the main component of alum.

Crystallization: The aluminium sulfate solution is then crystallized to produce alum crystals. Gypsum is often added during this step.

Bauxide is right answer because Bauxide have 58% alumina find.

You can't get alumina if you did not extract aluminum ore. Alumina is obtained after you remove all the impurities from the aluminum ore.

Why not alumina?

Gypsum is a sulfate mineral composed of calcium sulfate dehydrate, with the chemical formula CaSO42h2o. Bauxite is correct answer.

Please give the explanation.