Potassium carbonate

Potassium carbonate is the inorganic compound with the formula K2CO3. It is a white salt, which is soluble in water. It is deliquescent, often appearing as a damp or wet solid. Potassium carbonate is mainly used in the production of soap and glass.
History.
Potassium carbonate is the primary component of potash and the more refined pearl ash or salts of tartar. Historically, pearl ash was created by baking potash in a kiln to remove impurities. The fine, white powder remaining was the pearl ash. The first patent issued by the US Patent Office was awarded to Samuel Hopkins in 1790 for an improved method of making potash and pearl ash.
In late 18th-century North America, before the development of baking powder, pearl ash was used as a leavening agent for quick breads.
Production.
Potassium carbonate is prepared commercially by the reaction potassium hydroxide with carbon dioxide:
From the solution crystallizes the sesquihydrate K2CO3·H2O ("potash hydrate"). Heating this solid above 200 °C gives the anhydrous salt. In an alternative method, potassium chloride is treated with carbon dioxide in the presence of an organic amine to give potassium bicarbonate, which is then calcined: