History of Absorbents and Neutralizers
Activated charcoal is a common component of gas masks. It is a carbon with an extremely high surface area which attracts all manner of pollutants from air and water. Pollutants do not react with the carbon but are adsorbed into the pores. Over time the activated carbon becomes thoroughly coated and it ceases to remove pollutants. However, the charcoal can be reactivated and restored to its original state by baking the charcoal with high heat, which evaporates or burns off the pollutants.
The first effective filtering activated charcoal gas mask in the world invented in 1915 by Russian chemist Nikolay Zelinsky.
In the first gas masks of World War I, it was initially found that wood charcoal was a good absorbent of poison gases. In about 1918 it was found that charcoals made from the shells and seeds of various fruits and nuts such as coconuts, chestnuts, horse-chestnuts, and peach stones performed much better than wood charcoal. These waste materials were collected from the public in recycling programs to assist the war effort.
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