Application

The Uses of Ammonium Bicarbonate

Ammonium bicarbonate (also known as ammonium hydrogen carbonate) is produced by passing carbon dioxide gas counter currently through a descending stream of aqueous ammonia (ammonium hydroxide), usually in either a packed tower or an absorption column.

Food Industry

In the food industry, ammonium bicarbonate is used as a raising agent or leavening agent, as it releases gas in the baked good, creating a light texture. Examples include cookies and crackers, and steamed buns and Chinese almond cookies in China. Before modern day baking powder, it was also a staple good in households, for example in the form of hartshorn/hornsalt in Scandinavian countries. Although using ammonium bicarbonate does result in a slight ammonia smell during baking, it dissipates quickly and has no effect on the taste. However, ammonium bicarbonate cannot be used for moist, bulky baked goods, such as normal break or cakes, as some ammonia may remain trapped inside and result in an unpleasant taste.

Fertilizer

Ammonium bicarbonate is also widely used as a nitrogen fertilizer, especially in China, as the ammonium ions can be released into the soil and either absorbed by the soil colloid, lattice-fixed or converted into nitrate nitrogen. Its benefits are that it leaves little to no residue in the soil after the ammonium ion is absorbed by the plants, has minimum impact on the pH of the soil, and is quick-acting and useful in the long run. It is limited however due to its instability and tendency to decompose. This can however be remedied by the addition of a crystalline modifier.

Safety

Ammonium Bicarbonate irritates the skin, eyes, and the respiratory system, and short-term health effects can appear immediately or shortly after exposure. Inhalation can lead to coughing, wheezing, and/or shortness of breath due to irritation of the nose, throat, and lungs. Chronic exposure may lead to bronchitis along with the short-term effects. The health effects can last for months or years.

Operations involving ammonium bicarbonate should be carried out in enclosed conditions with local exhaust ventilation as much as possible. If not, respirators must be used, and protective work clothing is necessary. After exposure to ammonium bicarbonate, change clothes and wash them thoroughly.