Calcination is the decomposition or purification of a material (primarily mixed carbonate ores) through exposure to extreme heat in a limited air or oxygenated environment.
Although carried out in an extreme heat environment, the reaction that occurs is endothermic, because the treated materials absorb heat as such, remains cooler than its surroundings. It is generally a synthesised process but can sometimes occur naturally for example under layers of hot volcanic ash from an active volcano(Calcination, n.d.).
This process causes chemical changes such as the removal of volatile substances, decomposition of carbonates, or dehydration of hydrates. For example, calcination converts calcium carbonate (CaCO₃) into calcium oxide (CaO) and carbon dioxide (CO₂), or ferric hydroxide into ferric oxide and water vapor. It is an endothermic process carried out in furnaces like shaft furnaces, rotary kilns, or fluidized bed reactors and is used to prepare ores for further metallurgical treatment
Reference:
Calcination. (n.d.). [Commentary; Definition; Product Knowledge; Research, Development and Innovation]. https://www.designingbuildings.co.uk. Retrieved April 23, 2025, from https://www.designingbuildings.co.uk/wiki/Calcination
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