Barium hydroxide

How is barium hydroxide obtained?

Barium hydroxide is usually obtained from barite (barium sulphate) BaSO4, a mineral that occurs in nature. Barite is heated with coal to form barium sulphide BaS. 
This then reacts with water to form barium hydroxide and hydrogen sulphide:

BaS + 2 H2O -> Ba(OH)2 + H2S

Another possibility is to mix barium oxide BaO with water to obtain barium hydroxide:

BaO + H2O -> Ba(OH)2

What are the properties of barium hydroxide?

Barium hydroxide is a solid, colorless substance consisting of crystals. It is polymorphic, i.e. it can occur in different crystal structures. The stable form at room temperature is monoclinic and has the space group P 2 1 / n. The high-temperature form is orthorhombic and has the space group Pnma.

Barium hydroxide is slightly soluble in water, but the solubility increases with temperature. At 20 °C, 56 g/l of water dissolve, at 80 °C 947 g/l of water. The aqueous solution of barium hydroxide is also called barite water and has a pH value of 14, which means that it is very basic and can be neutralized with acids.

Barium hydroxide reacts with carbon dioxide or other carbonate-containing salts to form a sparingly soluble precipitate of barium carbonate:

Ba(OH)2 + CO2 -> BaCO3 + H2O

Barium hydroxide also reacts with other metal salts to form sparingly soluble barium salts, for example with sulphuric acid to form barium sulphate:

Ba(OH)2 + H2SO4 -> BaSO4 + 2 H2O

What are the advantages of barium hydroxide?

Barium hydroxide has a number of medical applications, particularly as a contrast agent for X-rays. Contrast agents are substances that make certain regions of the body or organs more visible on an X-ray image. Barium hydroxide is deposited on the walls of the stomach and intestines and thus creates a contrast to the surrounding tissues.

Barium hydroxide can be used in dogs to diagnose problems in the gastrointestinal tract, for example injuries, swallowed foreign bodies or organic diseases. Barium hydroxide can also contribute to a better diagnosis of other organs such as the heart, bladder, liver, kidneys or lungs.

What are the disadvantages of barium hydroxide?

Barium hydroxide also has some disadvantages and risks that you should be aware of. For one thing, it is a corrosive substance that can irritate or injure the skin, eyes and mucous membranes. You should therefore always wear protective gloves and goggles when handling barium hydroxide.

Secondly, it is a toxic substance that can lead to severe poisoning if swallowed or inhaled. The symptoms of barium poisoning include nausea, vomiting, diarrhea, abdominal pain, muscle weakness, cardiac arrhythmia or shortness of breath. You should therefore always make sure that your dog does not eat or inhale barium hydroxide.

Barium hydroxide can also have side effects when administered as a contrast agent. These include constipation, flatulence, abdominal pain or allergic reactions. It can also interact with other medications your dog is taking. You should therefore always inform your vet if your dog is given barium hydroxide.