Soda ash manufacturing routes: Which named industrial process is used in the ammonia–soda route for producing sodium carbonate (soda ash)?

Introduction / Context:
Sodium carbonate (Na2CO3), also called soda ash, is a bulk inorganic chemical used in glass, detergents, and pulp. The historical main production route is the ammonia–soda process, widely known by the name of its inventor, Ernest Solvay.

Given Data / Assumptions:

• Key inputs: brine (NaCl), ammonia, and CO2.
• Intermediate: NaHCO3 precipitates; calcination yields Na2CO3.
• Ammonia is recovered and recycled using lime (CaO) produced from limestone (CaCO3).

Concept / Approach:

The flow scheme carbonates ammoniated brine to precipitate sodium bicarbonate selectively. After filtration and calcination, soda ash is obtained. Byproduct CaCl2 forms in the ammonia recovery loop.

Step-by-Step Solution:

Verification / Alternative check:

Chemical engineering texts consistently label the route “Solvay.” Modern variants include natural trona processing but do not change the naming for the ammonia–soda process.

Why Other Options Are Wrong:

Each incorrect option names a different iconic process unrelated to soda ash manufacture.

Common Pitfalls:

Confusing Solvay with Sol-Gel (materials processing) or with downstream glass melting steps.

Final Answer:

Solvay process