Question

Explain the importance of ammonia in the Solvay Process. Help please :)

So i know that the Solvay process produces sodium carbonate and calcium chloride.
I know ammonia is needed at the very start of the production process but isn't needed to be added again after the initial addition of ammonia because of the "ammonia recovery" part of the solvay process.

But before that, ammonia gas is reacted with purified brine to form a highly alkaline brine solution (necessary in hydrogen carbonate formation) but i feel like i'm missing a lot of points that i should talk about? :/
Any help will be greatly appreciated :)

Answer 1

write down the reagents/reactants

Answer 2

Solvay process
\[CaCO_3 (s) \rightarrow CaO (s) + CO_2 (g) \]
\[NH _{4}^{+} (aq) + OH^- (aq) + NaCl (aq) + CO_2 (g) \rightarrow NaHCO_3 (aq) +NH_4Cl (aq)\]
\[2NaHCO_3 (s) \rightarrow Na_2CO_3 (s) + CO_2 (g) + H_2O (l)\]
\[CaO (s) + H_2O(l) \rightarrow Ca(OH)_2 (aq) \]
\[2NH_4Cl (aq) + Ca (OH)_2 (aq) \rightarrow CaCl_2 + 2H_2O (l) + 2NH_3 (g)\]

Answer 3

Overall Solvay Process reaction:
\[CaCO_3 (s) + 2NaCl(aq) \rightarrow Na_2CO_3 (aq) + CaCl_2 (aq) \]

But do i just focus on the parts involving ammonia?
\[NH_3 (g) + H_2O (l) + NaCl(aq) \rightarrow NH _{4}^{+} (aq) + OH^- (aq) +NaCl (aq)\]
^This is ammonia gas reacting with purified brine to form a highly alkaline brine solution
\[NH _{4}^{+} (aq) + OH^- (aq) + NaCl (aq) + CO_2 (g) \rightarrow NaHCO_3(aq)+ NH_4Cl(aq) \]
^This is CO2 (resulting from heating of limestone) reacting with the alkaline brine solution to produce sodium hydrogen carbonate and ammonium chloride
Then, calcium hydroxide (slaked lime) is reacted with the aqueous ammonium chloride to reclaim the ammonia and water which can be recycled in the reaction vessel.
\[2NH_4Cl (aq) + Ca(OH)_2 (aq) \rightarrow CaCl_2 (aq) + 2H_2O (l) + 2NH_3 (aq) \]

right? O.O

Answer 4

http://www.chem.tamu.edu/class/majors/chem470/Solvay.html

Answer 5

ohh okay :) Thank you!