Activated carbon It is generally used for high quality air purifier, because it can remove HEPA Harmful gas that cannot be solved by the filter. Now let's take a look at the importance of activated carbon in home and office air purification.

What material is activated carbon

Activated carbon filter is initially called HEGA( Efficient gas absorption ) filter. It was first used to remove chemical gases. Activated carbon is mainly provided in the form of powder or particles. Granular activated carbon or powdered activated carbon is often used in air filters. The service life of these activated carbon particles is much longer than that of powdered activated carbon. They are made by crushing solid carbon blocks into smaller particles. The activated carbon made from coconut shell is better than that made from wood or coal. The former has larger surface area and general porosity. Compared with wood and coal, coconut shells produce less dust and fine carbon particles. Activated carbon must be made through additional activation process to better capture gas molecules. Physical activation is to inject hot air, carbon dioxide or steam, while chemical activation is to soak various reagents to form a micro pore grid to capture gas molecules.

Usage of activated carbon

Activated carbon uses an adsorption process to remove pollutants from the air. It is almost similar to absorption, trapping the adsorbed material in its own pores. Absorption occurs when a fluid passes through or enters a liquid or solid absorbent. At the same time, if the atoms, ions or molecules of the fluid adhere to the surface of the liquid or solid adsorbent, it is called adsorption.

What pollutants can be removed by activated carbon

Activated carbon and air purifier, especially HEPA Air filters are used in combination. It is placed in the air purifier to capture and remove gas molecules and VOC etc. HEPA Contaminants that cannot be handled by the filter.

Tobacco smoke

Tobacco is made from seven thousand Composed of various chemicals, including seventy Species are carcinogenic, and one hundred and eighty Species are known to be harmful to health.

Volatile organic compounds (VOC)

Volatile organic compounds are very small gases released from certain solids or liquids. For example, smoke from burning wood or coal in a fireplace, or kerosene heaters and gas appliances ( Such as stoves and clothes dryers ) Smoke released. Indoor air pollution VOC The concentration is ten times higher than that outdoors. They can be suspended in the air for a long time and may be harmful to health. Similar to tobacco smoke, VOC It is composed of many dangerous chemicals that can cause cancer. The following can be found at home and in the office VOC Example:

Formaldehyde is a colorless and strongly smelling gas, which is usually used as a disinfectant and preservative in hospitals, and as an adhesive for building materials, appliances and furniture. However, this chemical is considered toxic to humans. Formaldehyde containing materials, such as wood products, fabrics, paints, etc., can release formaldehyde into the air in the form of gas or vapor. People exposed to formaldehyde may have tears in their eyes, burning sensation in their eyes, nose and throat, and skin irritation when inhaled. Formaldehyde also exists in tobacco smoke, fire smoke and automobile exhaust.

Benzene is a colorless or light yellow liquid chemical with a smell similar to petroleum. People can come into contact with benzene anywhere, because benzene is used to make rubber, dyes, glues, lubricants, paints, crude oil, gasoline, furniture wax, cleaning agents and cigarette smoke. However, heavy exposure to this chemical may have harmful effects on bone marrow and blood cells.

Naphthalene is a white, volatile, solid polycyclic hydrocarbon, made from crude oil or coal tar. It is used to make plastics, resins, fuels and dyes. It can also be found in cigarette smoke, car exhaust and forest fire smoke. Naphthalene in the form of camphor pills is used as an insecticide because solid products become toxic vapors over time. When you inhale naphthalene gas excessively or get pesticides on your skin, or accidentally eat or drink it, you will have a big trouble.

Chloroform is a man-made by-product formed when chlorine is added to water. It is a colorless transparent liquid with an odor similar to ether. When people inhale the air that releases chloroform, it may be toxic to humans. Generally, chloroform is used in construction, paper making, cardboard industry and film production.

Toluene is a clear colorless liquid from crude oil. It is usually added to gasoline and other vehicle fuels. It is also used as a solvent in the manufacture of paints, paint thinners, glues, nail polish, rubber and cigarettes.

Measure the performance of activated carbon in air purifier

Smoke and volatile organic compounds are small and dangerous particles. They can easily enter the blood through the lungs and are harmful to health when inhaled. This is why it is important to install an activated carbon filter in the air purifier. However, not all air purifiers with activated carbon filters have the same efficiency level when removing these particles. There are three key indicators to measure the performance of air purifier:

Clean air delivery rate (CADR) And air change rate per hour (ACH)

You can use its specified clean air delivery rate (CADR) To determine the air filter speed of the air purifier. use CADR The air purifier with high grade is a better choice. The higher the grade, the faster the filtering speed that the air purifier can provide. Formaldehyde CADR The same is true of ratings. If you want to quickly remove the VOC And smoke, please choose an air purifier with higher activated carbon content or high formaldehyde content CADR Grade air purifier.

Air changes per hour or ACH It indicates the frequency of air purifier to filter all air in the room within one hour. However, different types of rooms have different recommendations ACH 。 This is why it is also important to understand the function and size of the room before selecting an air purifier.

Cumulative cleaning quality (CCM)

　　CADR It does not represent the long-term performance of the air purifier. As the use time of the air purifier goes by, the filter may be blocked, and the performance will decline rapidly in just a few months. In order to understand the effect of the air purifier in filtering particles and formaldehyde in a few months, we need to compare their cumulative cleaning quality (CCM) 。 The measured values are converted into four levels for particulate matter and formaldehyde. The higher their removal value, the better the long-term performance of the air purifier. The current high performance value is particulate matter P4 And formaldehyde P4 。 But many companies have not disclosed their air purifiers CCM and CADR Rating, which makes it difficult for consumers to compare correctly.

The importance of activated carbon to air purifier, HEPA The filter is a harmful gas pollutant that cannot be handled. If you want to enjoy high-quality indoor air quality, you must choose to equip it with high-quality HEPA And activated carbon filter.