Stage 1 Purification and Ammoniation of Brine
In the first stage of the Solvay process, saturated brine is first purified. Metal ions like calcium ions (Ca2+), magnesium ions (Mg2+) and iron( lll) ions (Fe3+ ) are removed from the solution via precipitation reactions with carbonate ions (Co32-) and hydroxide ions (OH-). The impurities are then filtered out.
The purified brine is then allowed to flow into the ammoniation tower, which contains ammonia gas (NH3) . The ammonia gas dissolves in the brine to form ammoniated brine.