Filtration methods that are deployed in air filters and air purifiers will work to take in the indoor air in this environment and filter it of airborne pollutants such as chemical compounds, odorous compounds, and particulate matter present in the air space of the treated environment. Among the different types of air purifier technologies used for filtering the indoor air of a home or other personal indoor environment includes the most popular options like ozone, ionizers, and the most well-known and used activated carbon technology. Activated carbon filters are a versatile type of filtration method that is used in both water purification and air purification solutions – due to its inherit capability to filter and trap pollutants within the filter media of the activated carbon material.

In this article we are going to learn more about how well activated carbon works to filter indoor air, along with the disadvantages of using activated carbon filters in your air handling system or air purification device inside your home.

Activated Carbon vs Charcoal

Activated carbon is a technology that has many names including activated charcoal, charcoal, and carbon that will all work to filter indoor air of pollutants that may be accumulating within a confined space overtime. Whether you recently painted your home, installed new flooring, added a new pet to the family, or even cooked a family meal all day in your oven, pollutants will be produced in high concentrations throughout your home. The pollutants that may be brought into your home from various sources (like those listed above) can include chemical odors like VOCs, odorous compounds like urine, cooking smells, etc., and even particulate matter like pet dander and mold spores into the air.

However, when it comes to activated carbon vs charcoal there can be some confusion on the meaning of these two classifications of air filtration and if they in fact mean the same exact thing as one another. Charcoal is another name for carbon, and this refers to the untainted absorbent material that occurs prior to the activation of the material that is used to capture and trap pollutants within the media. When the charcoal (aka carbon) materials are activated either through physical (using hot gas) or chemical activation (using chemical agents like potassium permanganate), it will allow for the activated carbon to form a larger surface area which will allow for more contaminants to be stored on the carbon filter media. Penn State University’s research on activated carbon found that one pound of activated carbon contains a surface area of approximately 100 acres.

How Do Carbon Filters Work

How does carbon filtration work? The process in which activated carbon filters work when placed in an air filtration device or air system is through a method called adsorption. The activated carbon filter’s adsorption process works by trapping pollutants in the pore structure of the carbon and containing them in this filter until the carbon media fills up completely. Activated carbon is one of the most effective filtering methods for removing chlorine, sediment, volatile organic compounds (VOCs), and odors from the air. The typical particle sizes that can be removed by carbon filters range from 0.5 to 50 micrometers from the indoor air – a less efficient filtration method for filtering fine particulate matter than other technologies, such as HEPA filters.

Furthermore, the activated carbon possesses these capabilities because of the treatments it undergoes where oxygen is used to open up millions of tiny pores between the carbon atoms. These treatments to carbon filters are done to offer a filtration method that can be used to adsorb odorous and colored substances from gases and liquids in the air. The adsorption process on carbon filter material works by attaching these pollutants by chemical attraction, which means that eventually when the entire carbon filter fills up it will begin the slow re-releasing of the trapped pollutants back into the indoor air space, tainting the indoor environment once again.

How Long Does Activated Carbon Last in Filter

A big question about the effectiveness of activated carbon filters is how long does activated carbon last in an air filter when placed and used inside of an air handling system or air purifier. Although this is a great question, it is often a difficult one to answer since many variables will influence the lifespan of these filters inside of your personal indoor environment. The major factors to consider in your home that can exacerbate the life of the filter will include the amount of pollutants in the air (such as new floors installed, construction in the home, etc.), the airflow and ventilation in the space, and the overall size of the indoor space.

Additionally, the amount of carbon stored within the filter media that you are using in your home will also influence the life of the carbon filter. Those carbon filters that contain as much as 10lbs of carbon in its filter media will last for quite a while, whereas one that contains under 5lbs may be quickly used when placed in your home. On average, however, most carbon filters will only last for about a month to three months, based on carbon manufacturers.

Carbon Air Filter Disadvantages

Similar to nearly every other air filtration technology, activated carbon air filters will have several disadvantages that will be dealt with by those homeowners that decide to utilize this technology in their home’s air quality solutions like air handling systems and air purifiers. Among the drawbacks of using activated carbon for air filtration the top two disadvantages include the following; the filter replacement frequency and cost and the inability for carbon to completely remove and neutralize collected pollution on its filter media.

• Filter Replacement Cost: The process of removing fully saturated carbon filters can become inconvenient, a hassle, and costly for many people who use these methods in their indoor air quality products. Activated carbon filters are usually in need of being replaced more often than other filters due to the way that carbon filters work, by filling up by weight. Once the carbon filter becomes full, if it is not changed immediately, the filter will slowly begin to re-release the collected pollutants back into the indoor air that were once trapped on this filter media (acting like a sponge!). Thus, when this occurs it will render the carbon filter ineffective in its job of cleaning the indoor air.
• Lack of Pollutant Neutralization Capabilities: As we discussed above, carbon air filters are not able to neutralize and completely remove pollutants from the environment, rather they work by storing the pollutants onto the filter media trapping them in the activated carbon material. However, when the carbon filter fills up completely it will re-release the collected pollutants off the filter and into the indoor space it once cleaned. Additionally, carbon filters are not able to collect fine particulate matter and thus this is a downfall for many people who want these pollutants removed from their home’s air as well.

Learn more about how carbon compares to the EnviroKlenz® technology used in the EnviroKlenz Air Purifier and HVAC Filter!