Barium chloride is an inorganic compound which commonly exists in its dihydrated form, BaCl2(H2O)2. It is a hygroscopic compound and appears as white powder. It is toxic and imparts a yellow-green coloration to a flame. Due to its toxicity, it has limited use in industry and laboratory. It has a density of 3.097 g/cm3 and has a boiling point of 35.7oC. It is soluble in water and alcohol. It can also slightly dissolve in hydrochloric acid, nitric acid.
It is prepared from barium sulfate (barite) in the industry through a two-step. The first step involves the addition of carbon to barite, to form barium sulfide (BaS) at an elevated temperature. After which, barium hydroxide or barium carbonate is added to give hydrated barium chloride.
Waste Water Industry
Barium chloride dehydrate is commonly used in waste water treatment. It is mainly used in the purification of brine solution in caustic chlorine plants.
Being cheap and as a soluble salt of barium, it is commonly used as a test for sulfate ions. However, due to its toxicity, its uses are limited.
Barium chloride is also used in the production of heat treatment salts, case hardening of steel, pigments, and as a precursor for other barium salts. It is also found in fireworks where it contributes to the color green.