Which of the following reactions is not involved in Solvay process?
a) CaCO,»CaO +CO,
3) NaCINH, +CO, +1,0 ► NH,Cl + NaHCO,
- Ca0+ 2NH CI+ 2NH, #CaC1, +2H0
) Na 00, +CO, +H,0 - 2NaHCO,
Answers
Explanation:
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.