Editing Bone char (section)

==Production==
Bone char is primarily made from cattle and pig bones; however, to prevent the spread of [[variant Creutzfeldt–Jakob disease|Creutzfeldt–Jakob disease]], the [[skull]] and [[Vertebral column|spine]] are no longer used.<ref name="Dirty Jobs: Episode Guide">{{cite web|url=http://dsc.discovery.com/fansites/dirtyjobs/episode/episode.html |title=''Dirty Jobs'' Episode Guide: Season 5 Episode "Bone Black" |archive-url=https://web.archive.org/web/20101113011609/http://dsc.discovery.com/fansites/dirtyjobs/episode/episode.html|archive-date=November 13, 2010}}</ref> The bones are heated in a sealed vessel at up to {{convert|700|C|F}}; the oxygen concentration must be kept low while doing this, as it affects the quality of the product, particularly its [[adsorption]] capacity. Most of the [[organic compound|organic]] material in the bones is driven off by heat, and was historically collected as [[Dippel's oil]]; that which is not driven off remains as [[activated carbon]] in the final product. Heating bones in an oxygen-rich atmosphere gives [[bone ash]], which is chemically quite different.{{Clarify|reason=Calcining bones means burning them in oxygen atmosphere.|date=December 2021}}{{Citation needed|date=December 2021}}

Used bone char can be regenerated by washing with hot water to remove impurities, followed by heating to {{convert|500|C|F}} in a [[kiln]] with a controlled amount of air.