How are bitterns used to make products such as bromine, potash, and magnesium compounds?

Bitterns are the concentrated, bitter-tasting liquid remaining after sodium chloride (table salt) has been removed from brines or seawater through evaporation and crystallization. Because this residual solution contains high concentrations of magnesium, bromide, and other salts, it serves as a valuable commercial source for various chemical products.123

The manufacturing processes for these compounds include:

• Magnesium Compounds: Bitterns are a primary source for magnesium sulfate (Epsom salts), magnesium chloride, and magnesium bromide.12
• Bromine: To extract bromine, the brine or seawater is typically acidified with sulfuric acid and treated with chlorine, which displaces the bromine from the bromides. The bromine is then removed via an air current and concentrated through further chemical treatment.4
• Potash: In industrial operations, such as those in the United States and Israel, bitterns are processed to recover potash alongside these other mineral components.2

These extraction methods allow industries to maximize the utility of brine resources beyond the initial production of table salt.2