Potassium carbonate (K2CO3) is a white salt, soluble
in water (insoluble in ethanol), which forms a strongly alkaline solution. It
can be made as the product of potassium hydroxide's absorbent reaction with
carbon dioxide. It is deliquescent, often appearing a damp or "wet"
Potassium carbonate is prepared commercially by the
electrolysis of potassium chloride. The resulting potassium hydroxide is then
carbonated using carbon dioxide to form potassium carbonate, which is often
used to produce other potassium compounds.
2KOH + CO2 → K2CO3 + H2O
Potassium carbonate is used as a mild drying agent where
other drying agents, such as calcium chloride and magnesium sulfate, may be
incompatible. It is not suitable for acidic compounds, but can be useful for
drying an organic phase if one has a small amount of acidic impurity. It may
also be used to dry some ketones, alcohols, and amines prior to distillation. Potassium carbonate is also used to make a safer electrolyte for oxyhydrogen production
than potassium hydroxide, the more commonly used electrolyte.
As food additive, it is used as an ingredient
in the production of grass jelly. It is used to tenderize tripe. German gingerbread
recipes often use potassium carbonate as a baking agent. It is also used as a buffering agent in the production of mead or wine.
Potassium carbonate as a fire suppressant in
extinguishing deep-fat fryers and various other B class-related fires. Potassium carbonate is also used as an animal feed ingredient to satisfy the potassium
requirements of farmed animals such as broiler breeders.