Activated Carbon:

Air purifiers use activated carbon filters to eradicate airborne gases and odors. Also known as activated charcoal or activated coal, activated carbon is an extremely porous substance that has a large surface area suitable for absorption of molecular particles. To be considered 'active,' the carbon, or a carbon-rich substance such as wood, nutshells, or coal, must be put through the carbonization process to draw the individual carbon atoms away from each other creating numerous pores, nooks, and crannies. Carbonization takes place when "the raw carbon source is slowly heated in the absence of air to produce a high carbon material. The carbon is activated by passing oxidizing gases through the material at extremely high temperatures." Under a microscope, a granule of activated carbon resembles a well engineered ant farm. The millions of tiny pores trap particles in the air as they make their way through the expansive sea of enriched element.

Activated carbon can be used in all sorts of filtration applications. Found to be used by the ancient Egyptians around the year 2,000 BC carbon filtering is believed to be one of the oldest forms of water filtration in existence. Since then it has also proven to be effective in gas purification, metal extraction, sewage treatment, military gas masks, and of course air purification. In air purification, activated carbon is widely used to work in conjunction with other types of filters (pre-filters, HEPA, etc.) Since particles come in many different sizes and carbon only bonds with certain organic materials and gases, it cannot be used as an independent filtration method. Some examples of materials susceptible to being adsorbed by activated carbon are: chlorine and chlorine by-products, man-made and naturally occurring carbon-base volatile organic compounds (VOC's), and radon.

Activated carbon comes in a variety of forms. The most popular being: powdered (PAC), granular (GAC), extruded (EAC), and impregnated. It is also available in textile forms such as carbon mesh and fabrics. While all of these forms may not be used in air purification, each works in the same general way. For each type of activated carbon there is a different pore size and surface area. Using the process of 'adsorption,' the element works like a sponge absorbing water by way of chemical reaction. The carbon draws in organic particles, fumes, and gases and bonds with them on the surface to prevent them from being re circulated back out into the air. At PureAirProducts.com we stock an impressive selection of air purifiers from brands like IQAir, BlueAir, and more that feature powdered and granular activated carbon filters.

IQAir: http://www.pureairproducts.com/airpurifier-iqpa1702.htm
BlueAir: http://www.pureairproducts.com/airpurifiers-blupa8001.htm

It is important to regularly replace your activated carbon filters. Over time, every pore in each morsel of activated carbon can become packed with toxins, chemicals, and odor particles. This causes the carbon to lose its ability to effectively filter out unwanted particulates. Once a pore has taken on as many particles as it can, it cannot take on anymore. This is where the valuable surface area comes in. Granules of activated carbon are so porous that a minute amount can be spread out across a massive area. For instance, a teaspoon of activated carbon can have the surface area of a football field. Activated carbon is costly to recycle, but inexpensive to manufacture, which is why most activated carbon filters need to be disposed of when the element has reached its full adsorption capacity (please check with your local sanitation department or recycling center for guidelines on how to properly dispose of an activated carbon filter). To make things easy, we offer a complete line of replacement carbon filters that are easy to install and help keep the air in your home or office fresh and clean.