Calcium oxide

**Production and Properties:**
– Calcium oxide is produced by thermal decomposition of materials containing calcium carbonate through a process called calcination or lime-burning, liberating carbon dioxide.
– The annual worldwide production of calcium oxide is around 283 million tonnes.
– Quicklime, a form of calcium oxide, has a high affinity for water and is a desiccant.
– Calcium oxide is a distinct mineral species with the unit formula CaO, known as Lime, with unique properties and crystal structure.

**Industrial and Mining Applications:**
– Calcium oxide is a key ingredient in various industrial processes, including cement production, basic oxygen steelmaking, and aerated concrete production.
– It is used in mining for rock breaking, in the petroleum industry for water detection, in paper production for chemical recovery, and in plaster production for flooring and construction.
– The chemical is utilized in carbon capture and storage processes and in flue-gas desulfurization in chemical or power production.

**Historical and Military Uses:**
– Historically, calcium oxide has been used to enhance the durability of ancient Roman concrete and accelerate the decomposition of corpses.
– In warfare, it has been used as a weapon by Roman generals and potentially in medieval naval warfare, including in lime-mortars to attack enemy ships.
– English Navy reportedly used quicklime to blind an invading French fleet, and it may have been a component of Greek fire.

**Substitutes and Alternatives:**
– Limestone, calcined gypsum, cement, fly ash, and magnesium hydroxide are potential substitutes for calcium oxide in various applications like agriculture, construction, and pH control.
– Magnesium oxide can replace dolomitic lime as a flux in steelmaking.
– Limestone, despite being slower to react, is considerably cheaper than calcium oxide.

**Safety and Hazards:**
– Quicklime can cause severe irritation when inhaled or in contact with moist skin or eyes, leading to coughing, burns, nausea, and vomiting.
– Safety precautions are necessary due to the vigorous reaction of quicklime with water, which can release enough heat to ignite combustible materials.
– While quicklime is not considered a fire hazard, proper handling is crucial to avoid accidents.https://en.wikipedia.org/wiki/Quicklime