Baeyer's process is used to concentrate bauxite ore to alumina

Baeyer's process is used to concentrate bauxite ore to alumina.

Give balanced chemical equations for the reaction taking place for its conversion from bauxite to alumina.

Answer

(i) Al₂O₃.2H₂O + 2NaOH → 2NaAlO₂ + 3H₂O (Reaction at 150º-200º C)

(ii) NaAlO₂ + 2H₂O → NaOH + Al(OH)₃ (Reaction at 50º-60º C)

(iii) 2Al(OH)₃ → Al₂O₃ + 3H₂O (Reaction at 1100ºC)

• Exam Year: 2020