Calcium chloride is a type of salt derived from limestone. It is also produced as a byproduct of the ammonia-soda process of making soda ash. This type of salt has several properties that make it useful in commercial, industrial, and medical applications. The compound prevents water from freezing, absorbs moisture from the air, and generates heat when wet. Its medical uses include treatment for calcium disorders, certain heart conditions, and toxicity issues.
Roads are often treated with calcium chloride during freezing conditions. It keeps roads free from ice by melting existing ice and lowering the freezing point of water. The compound is also applied to unpaved roads to prevent dusty conditions. It does this by absorbing water from the air, keeping a thin layer on top of the road moist. Other commercial applications include adding it to concrete to speed up curing time and using it as a packaging desiccant to prevent moisture from harming delicate electronics.
Patients with magnesium intoxication or calcium channel blocker toxicity are treated with intravenous injections of calcium chloride. In some cases, the compound is used for emergency cardiac resuscitation. It is also used to treat hypocalcaemia, a medical condition that sometimes requires an emergency infusion of the compound.
Calcium chloride is found in many foods. It is used to add a salty taste to pickles without raising sodium levels. Canned foods, such as green beans, retain their firmness when treated with the salt. It is added to many sports drinks to help athletes maintain their electrolyte balance. Some cheeses are made by first adding the compound to milk or milk products.
Many products that control moisture in closets and basements use calcium chloride as the main desiccant. Portable hand warmer packs and heating pads utilize the compound’s ability to generate heat when moistened. Fabric softeners often use the compound to improve the liquid’s viscosity because it absorbs water and holds it in suspension. It is a salt mineral and is used in swimming pool maintenance to increase the hardness of the water.
Marine aquariums use calcium chloride to increase the calcium content of the water. Certain marine animals, such as mollusks, require water with extra dissolved calcium to maintain health. Tires are sometimes weighted with the compound. It is mixed with water and injected into the air space of the tires. This adds extra weight and drag to the tires while preventing the water from freezing and damaging them.