![]() Small quantities of quicklime are used in other processes e.g., the production of glass, calcium aluminate cement, and organic chemicals.They do this by reacting with finely divided silica and alumina to produce calcium silicates and aluminates, which possess cementing properties. Quicklime and hydrated lime can considerably increase the load carrying capacity of clay-containing soils.Ground quicklime is used in the production of aerated concrete such as blocks with densities of ca.The quicklime neutralizes the acidic oxides, SiO 2, Al 2O 3, and Fe 2O 3, to produce a basic molten slag. Its usage varies from about 30 to 50 kilograms (65–110 lb) per ton of steel. The major use of quicklime is in the basic oxygen steelmaking (BOS) process.The temperature can reach up to some 300 ☌ (572 ☏). ![]() After a while, a pronounced exothermic reaction occurs ('slaking of lime'). ![]() Drops of water are added to pieces of quicklime. Uses A demonstration of slaking of quicklime as a strongly exothermic reaction. The reaction of quicklime with water is associated with an increase in volume by a factor of at least 2.5. Quicklime has a high affinity for water and is a more efficient desiccant than silica gel. Īpproximately 1.8 t of limestone is required per 1.0 t of quicklime. The United States is the next largest, with around 20 million tonnes per year. China is by far the world's largest producer, with a total of around 170 million tonnes per year. The quicklime is not stable and, when cooled, will spontaneously react with CO 2 from the air until, after enough time, it will be completely converted back to calcium carbonate unless slaked with water to set as lime plaster or lime mortar.Īnnual worldwide production of quicklime is around 283 million tonnes. This is also one of the few chemical reactions known in prehistoric times. This is accomplished by heating the material to above 825 ☌ (1,517 ☏), a process called calcination or lime-burning, to liberate a molecule of carbon dioxide (CO 2), leaving quicklime behind. Both it and the chemical derivative calcium hydroxide (of which quicklime is the base anhydride) are important commodity chemicals.Ĭalcium oxide is usually made by the thermal decomposition of materials, such as limestone or seashells, that contain calcium carbonate (CaCO 3 mineral calcite) in a lime kiln. ![]() Calcium oxide that survives processing without reacting in building products, such as cement, is called free lime. By contrast, quicklime specifically applies to the single compound calcium oxide. The broadly used term lime connotes calcium-containing inorganic compounds, in which carbonates, oxides, and hydroxides of calcium, silicon, magnesium, aluminium, and iron predominate. It is a white, caustic, alkaline, crystalline solid at room temperature. Calcium oxide ( formula: Ca O), commonly known as quicklime or burnt lime, is a widely used chemical compound. ![]()
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