Air filtration is all about making the air cleaner. And what could be greener than removing contaminants from the air? In this post, we’ll take a look at why that may not necessarily be the case, depending how the air is filtered.
Activated Carbon: A Dirty Solution for Cleaning Air
Activated carbon is one of the most common materials used for cleaning chemicals from air. In 2016, 577 million tonnes of activated carbon will be used for air purification purposes, mostly for the industrial market. It is certainly very green to remove contaminants from air used in polluting processes, especially in this industrial market. However, producing the activated carbon itself is not a particularly green process, which negates some of the effects of removing the actual pollutants
Activated carbon is derived from elemental carbon, charcoal, or some kind of other carbon-rich precursor. This precursor is then either given a high-temperature chemical treatment, or is treated via pyrolysis (high temperatures) and then oxidation (exposure to oxygen). After the activation process, the activated carbon may be further treated with a polymer coating or impregnation with other elements to increase its functionality.