Barium Sulfite can be
prepared by reacting sodiumsulfite with bariumchloride:
BaCl2+ Na2SO3→BaSO3+ 2NaCl
Barium Sulfite occurs as white,
monoclinic crystals with a density of 4.44 g/cm3. Its
solubility in water is low (0.001125 g/100 ml) and it is
insoluble in ethanol. When heated, it decomposes at
480°C to the oxide and SO2 gas.
It has been used as a weighting material on oil-drilling
rigs to prevent “blow out” during drilling operations.
This salt is used for such purposes, presumably
because of its ability to absorb SO2 and H2S gases trapped in the rocks as drilling proceeds. The demand for barium sulfite is low.
Barium sulfite is available in limited quantities,
commercially.