The process that converts organic matter into carbon by destructive distillation is carbonization.
Carbonization is a heat-driven pyrolytic process in which organic material loses hydrogen, oxygen, and other volatile components. Wood, for example, can leave behind a carbon-rich solid residue called charcoal, while gases, vapors, and tar may also be released. The process can occur naturally during intense volcanic or fire exposure and can also be controlled industrially.
Carbonization is closely related to pyrolysis, but the terms are not exact synonyms. Pyrolysis means thermal decomposition in little or no oxygen and can produce gases, liquids, or solids. Carbonization emphasizes the formation of a carbon-rich residue. Combustion, by contrast, is oxidation that generally consumes the material and produces carbon dioxide, while gasification converts carbonaceous feedstocks mainly into combustible gases.
Historically, charcoal production used covered wood kilns to limit oxygen and prevent complete burning. Carbonization also plays a major role in coal formation, carbon-fiber production, coke making, and the preparation of activated carbon.