Potassium carbonate, the main component of potash and was primarily derived from mined salt potash. The old method was collecting or producing from wood ash (1). Currently, it is mainly synthetically produced by the following three manufacturing processes (2):

1. Obtaining potassium hydroxide first by electrolysis of potassium chloride and then reacting with carbon dioxide. Chlorine (Cl2) and hydrogen (H2) are the byproducts.  

2. Treating a solution of potassium hydroxide with excess carbon dioxide.

3. Carbon dioxide gas is passed into the potassium hydroxide solution to produce potassium bicarbonate first, then heated.

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