Ammonium carbonate

Raw materials

1. Ammonium chloride

2. Chalk

Process

1. A mixture of ammonium chloride and chalk is heated to redness in iron retorts, the vapors being condensed in leaden receivers. 

2. The crude product is refined by sublimation, when it is obtained as a white fibrous mass, which consists of a mixture of ammonium bicarbonate, NH₄HCO₃, and ammonium carbonate, (NH₄)₂CO₃, in molecular proportions; on account of its possessing this constitution it is sometimes called ammonium polycarbonate (has a strong ammonium smell, and on digestion with alcohol the carbonate is dissolved and a residue of ammonium bicarbonate is left; a similar decomposition taking place when the polycarbonate is exposed to air).

3. Ammonia gas passed into a strong aqueous solution of the polycarbonate converts it into normal ammonium carbonate, (NH₄)₂CO₃, which can be obtained in the crystalline condition from a solution prepared at about 30 °C. This compound on exposure to air gives off ammonia and passes back to ammonium bicarbonate which has pH of 9.

Product

Ammonium carbonate

Used as

Smelling salt, leavening agent in particular recipes (particularly those from northern Europe and Scandinavia), an active ingredient in Buckley's cough syrup from Canada intended to help relieve symptoms of bronchitis, an emetic (a substance that induces vomiting)

Production facility

Cairns, QLD

Export

Yangon, Myanmar