Activated Carbon , how does it help?

Activated carbon is a special form of coal: It consists largely of the chemical element carbon (C). That's why activated carbon can be made from many natural carbon-containing substances - e.g. hard coal, coconut shells, sugar, wood, corn cobs, lignin, bamboo, apricot kernels and much more. The remarkable thing about activated carbon is that its fine-grained structure has a particularly porous structure.

What's special about it? The highly porous structure is similar to that of a sponge. Therefore, even a few grams of activated carbon have an extremely large surface area , which gives it invaluable value - for example for use as a cleaning or filter medium in industry, medicine, water treatment, air conditioning and ventilation technology.

Fun Fact-

The internal surface area of ​​four grams of activated carbon corresponds approximately to the area of ​​a football field. High-quality activated carbon has a surface area of ​​more than 1500 m² per gram! The more surface area there is, the more substances can be bound (adsorbed).

List of possible areas of application for activated carbon

• Medical treatment for poisoning
• Tar filter for cigarette or tobacco pipes
• Ventilation of shelters
• Exhaust air filters in production plants
• Insoles in shoes (removal of sweat smell)
• Pollutant filters in aquariums and ponds
• Cabin air filters in transportation (e.g. air conditioning in airplanes, trains, cars, etc.)
• Filtering in the production of spirits (e.g. flavors & colorings in vodka & rum)
• Removal of fermentation by-products in the production of beer
• Exhaust air filters for tank systems (e.g. gasoline vapors)
• Exhaust air filters in nuclear power plants (minimization of radioactive noble gases)
• Medication for gastrointestinal diseases (e.g. charcoal tablets)
• Chemical cleaning of industrial gases (e.g. CFCs)
• Colorant (E153) in the food industry (jellies, jams, confectionery, cheese)
• Cosmetic agent in creams, face masks & shower gels (scientifically controversial!)
• As a neutralizer of tooth discoloration in toothpaste (scientifically controversial!)
• Drinking water filter in the household (odor-disrupting substances, germs, bacteria, chlorine, and much more)
• Special filters for the military (e.g. for gas masks, in tanks or shelters from NBC weapons, etc.)
• Industrial filter systems
• Water filters in sewage treatment plants
• Desiccant in baby diapers

Activated carbon as a filter medium for water

The fine surface structure of activated carbon can of course also be used to filter water , with many positive effects. In industry, contaminated water is recycled or purified on a large scale. So contains e.g. For example, the wastewater in textile dyeing plants contains dyes that can often only be removed by adsorption with activated carbon.

Sewage treatment plants in German municipalities and large cities also make use of the properties of activated carbon. Municipal wastewater can contain a variety of contaminants, which are divided into different groups of pollutants, including:

• dissolved and undissolved substances,
• organic substances that are easily or difficult to decompose, 
• plant nutrients,
• heavy metals,
• Chlorine,
• salts, 
• and much more

Although activated carbon is particularly suitable for contamination with organic compounds , it is only partially effective or ineffective for some substances.

ACTIVATED CARBON

FILTERS

• chlorine
• Heavy metals (lead, copper, etc.)
• Drug residues
• Hormones
• Pesticides
• asbestos fibers
• Legionella
• Germs & bacteria
• Plant protection products
• Microplastics
• Tastes & smells

ACTIVATED CARBON

DOESN'T FILTER

(OR BARELY)

• Minerals* 
• Trace elements*
• Lime (only to a limited extent)
• ammonia

*a positive effect for water filters, as the minerals and trace elements are very good and important for the body.  

 

Activated carbon filters – different types at a glance

Poured activated carbon

• Conventional table can filters work based on loosely poured activated carbon. 
• If the activated carbon is only poured loose, the filter ensures a better taste and smell of the water, but largely fails to filter pollutants. 
• A table can filter is good at removing limescale, but the ion exchange resin added to it is saturated quite quickly. 
• In addition, a table can filter is not able to reliably filter residues of microplastics, medications or hormones. 
• And because a table water filter comes into more contact with sunlight, there is a greater risk of germ contamination
• Germ contamination occurs particularly when the filter medium is not changed in a timely manner.

Extruded activated carbon

• An activated carbon block can also consist of extruded activated carbon.
• In this variant (a lot of) binder is used to “activate” the carbon.
• However, extruded activated carbon does not offer as high porosity as sintered activated carbon.

(Sintered) activated carbon blocks

• High-quality activated carbon block filters can remove the pollutants listed in the table above from the water.
• Particularly high-quality activated carbon block filters can also be made with sintered activated carbon. 
• The process of sintering optimizes the “performance” of the activated carbon by maximizing the absorption capacity of the activated carbon. 
• Sintered activated carbon has a particularly high adsorptive (i.e. “absorbing”) effect and therefore a strong filter performance.

Frequently asked questions briefly explained

What is activated carbon good for?

Activated charcoal is also called "medical charcoal", but its use in medicine (e.g. for gastrointestinal diseases) does not tell the whole story. Activated carbon is used as a cleaning filter medium, for example. B. also in air conditioning, in industrial plants, in nuclear power plants and even in the military.

How does activated carbon work?

The special thing about activated carbon are the ultra-fine pores, which are connected to each other in a labyrinth and therefore form a large surface area. There is enough space there and any pollutants or toxins will stick . Activated carbon is becoming a valued material precisely because of its enormous binding properties (adsorption abilities).

What is sintered activated carbon?

Sintered activated carbon is a special form of activated carbon. Sintering optimizes the “performance” of the activated carbon by maximizing the absorption capacity , i.e. the number of pores.

Is activated carbon harmful?

Apart from the activated carbon in toothpaste , which may accelerate the abrasion of tartar, activated carbon is harmless. However, experts warn when it comes to food: Charcoal not only binds pollutants and toxins in the body, but also vitamins and minerals. These should be better absorbed by the body through food. 

Is activated carbon flammable?

Activated carbon consists predominantly of carbon (usually > 90%) with a highly porous structure and is flammable ¹² .

What does an activated carbon filter do?

As a potent cleaning and filter medium, activated carbon is of great value for medicine, chemistry, water treatment, ventilation technology, agriculture and recently also for the cosmetics and food industries. However, their value in the last two areas of application is highly scientifically controversial.