Sodium carbonate is manufactured by Solvay process, the products that are recycled are
(1) CO2, and NH3
(2) CO2, and NH4CI
(3) NaCl and Cao
(4) CaCl2, and CaO
Answers
Answer:In Solvay process, also known as ammonia soda process, carbon dioxide is passed through a brine solution (containing about 28 % NaCl) which is saturated with ammonia to form sodium carbonate.
2NH
3
+H
2
O+CO
2
→(NH
4
)
2
CO
3
(NH
4
)
2
CO
3
+H
2
O+CO
2
→2NH
4
HCO
3
NH
4
HCO
3
+NaCl→NaHCO
3
↓+NH
4
Cl
The precipitate of sodium bicarbonate is filtered, dried and ignited to form sodium carbonate.
2NaHCO
3
heat
Na
2
CO
3
+CO
2
+H
2
O
The carbon dioxide required for the reaction can be obtained by heating limestone (calcium carbonate) to 1300 K in a lime klin. Lime dissolves in water to form calcium hydroxide which is then transferred to the ammonia recovery tower.
CaCO
3
heat
CaO+CO
2
CaO+H
2
O→Ca(OH)
2
Ammonia required for the process can be prepared by heating ammonium chloride with calcium hydroxide.
2NH
4
Cl+Ca(OH)
2
2NH
3
+CaCl
2
+H
2
O
Hence, the only byproduct of the reaction is calcium chloride.
Explanation: