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Carbon filter

noob25002

Member
Sep 16, 2018
73
2
41
I'd like to know more about carbon filtration for an air purifier.

From what I read so far they can be as a foam like material, carbon pellets and a hybrid with a hepa filter.

Does more carbon result in better performance or just slower saturation?

How to those filters that have just a foam carbon filters compare with a hepa/carbon hybrid?

Thank you.
 

sdifox

No Lifer
Sep 30, 2005
86,649
10,175
126
Well if you have more activated carbon exposed to the 'dirty' air, obviously it is going to trap more particulates. Useful life of the filter thus gets extended.
 

noob25002

Member
Sep 16, 2018
73
2
41
Well if you have more activated carbon exposed to the 'dirty' air, obviously it is going to trap more particulates. Useful life of the filter thus gets extended.
But how efficient are between themselves, generally speaking, the types of carbon filters mentioned above?

Also is ionization on air purifier dangerous in a sealed 30 sq/m2 room?
 

[DHT]Osiris

Diamond Member
Dec 15, 2015
9,578
5,711
146
But how efficient are between themselves, generally speaking, the types of carbon filters mentioned above?
Efficiency is relative, do you want it to be efficient by not replacing it every day? Get less surface area of activated carbon. Do you want it more efficient at capturing stuff? More surface area.
Also is ionization on air purifier dangerous in a sealed 30 sq/m2 room?
Why would it be?
 

Meghan54

Lifer
Oct 18, 2009
10,446
3,452
136
Efficiency is relative, do you want it to be efficient by not replacing it every day? Get less surface area of activated carbon. Do you want it more efficient at capturing stuff? More surface area.

Why would it be?
Ozone.
 

snoopy7548

Diamond Member
Jan 1, 2005
6,987
3,860
136
Nice try, SaltyNuts. You can't filter your muriatic acid fumes through a carbon filter and expect to breathe in the vapors... or can you?
 

noob25002

Member
Sep 16, 2018
73
2
41
So I got something like an Winix 5500-2. Has a pellet like active carbon filter, cold catalyst filter and anti bacterian filter, hepa, etc.
Besides this one I also have a Sharp model with an hybrid hepa/carbon filter.
Also got a Huma-i (HI-150) and a second air quality monitor.

For particles the filters clearly do something, but for VOC gasses the purifiers seem to make no difference. With windows closed the levels just rise.
Room is ~20 square meters / 215 sq ft.

Any explanation?
 

BoomerD

No Lifer
Feb 26, 2006
58,070
6,268
126
So I got something like an Winix 5500-2. Has a pellet like active carbon filter, cold catalyst filter and anti bacterian filter, hepa, etc.
Besides this one I also have a Sharp model with an hybrid hepa/carbon filter.
Also got a Huma-i (HI-150) and a second air quality monitor.

For particles the filters clearly do something, but for VOC gasses the purifiers seem to make no difference. With windows closed the levels just rise.
Room is ~20 square meters / 215 sq ft.

Any explanation?
Because you seem too stupid to actually google it...


Can carbon filters remove VOCs effectively?
Carbon filters are specifically designed to remove gaseous elements from the air and may effectively remove volatile organic compounds in the short term. However, it is possible that some of these gases can release back into the air because of the science behind the technology.

Carbon air filters remove pollutants from the air with a process known as ad-sorption, not ab-sorption. The key difference here is that during adsorption, the pollutants stick to the outside of the tiny carbon particles in the filter’s adsorption bed. Whereas with absorption, the pollutants are held inside the structure itself – as with a sponge.

The process of adsorption allows carbon air filters to filter airborne chemicals (gases) from the air. Typically, these filters use activated carbon (charcoal, etc.) in the adsorption bed, which is full of tiny holes that create a very large surface area for pollutants to stick to.

However, there are two problems with activated carbon filters that you should be aware of:

  • Over time, the surface area of the activated carbon fills up and becomes saturated, meaning that the filter can no longer trap pollutants. In this situation, the filter will stop removing VOCs from the air and can even begin to release VOCs it has trapped back into the air. As a result, it is vital that you change your carbon filter regularly to avoid off-gassing.
  • The second problem carbon filters face is that their ability to absorb and store pollutants is highly dependant on the humidity and ambient temperature of the room. Water molecules compete for space in the adsorption bed and could kick out the VOCs already there, and heat may cause the VOCs to revert back to a gas. As a result, if you were to open a window in the room or turn on the heating it could cause the carbon to start releasing VOCs it has previously trapped back into the air.
(yes, they're trying to sell you their product)


Volatile Organic Compounds (VOCs) are one of the greatest hazards to workers in the gas and oil industry. Comprised of toxic chemicals such as benzene and toluene, these airborne contaminants can have long-lasting negative consequences on your workers. Repeated exposure to these compounds can result in gastrointestinal disorders, respiratory illness, cancer, and even death. The removal of VOCs from your worksite is of the utmost importance to ensure employee safety, cut maintenance costs, and adhere to regulatory standards.

Mechanism of Action
Bulk activated carbon facilitates in the removal of VOCs by removing contaminants and impurities from the air through chemical adsorption. Acting as a tiny prison cell for VOCs, it attracts and traps them within its porous surface, completely scrubbing these noxious compounds from the air. Activated carbon has a higher success rate in the removal of VOCs from polluted air due to its hardiness and resistance to mechanical breakdown. Furthermore, it has a higher retention rate due to its extreme porosity in a comparatively small area. Its incredible efficiency makes using bulk activated carbon a low-cost and reliable means to eliminate unwanted contaminants from your jobsite.

Types of Bulk Activated Carbon
There are three primary formulas of bulk activated carbon to choose from when looking for a filter to aid in the removal of VOCs: wood, coconut, and charcoal. With its larger pore size, wood-based carbon is a fine choice when your particulates are also of a larger diameter. However, because it contains only macro-pores, its utilization is limited. Charcoal-based bulk activated carbon is another good choice for the removal of VOCs, but again, it has its limitations. Its pore size is smaller than the wood-based carbon's pore size, plus it has the added benefit of being harder and more durable. Coconut-based bulk activated carbon is unquestionably one of the most superior types of activated carbon for successful removal of VOCs from the air. With almost 90% of its surface area comprised of micro-pores the same size of the molecules you're trying to remove, it's easily renewed and affordable, making it an excellent choice for your application.

Thorough removal of VOCs from your jobsite is essential due to the far-reaching and devastating effects that these compounds can incur. The government is tightening their regulations on pollutants, and failure to comply with them can result in heavy fines. Fortunately, it's both easy and economical to protect your workers and your investment. Contact us today to see how our bulk activated carbon can optimize your productivity and assist you in the removal of VOCs from your jobsite.
(yes, they're also trying to sell you their coconut carbon product...for good reason. Coconut carbon is the most effective and efficient type for removing things like VOC's.)
 

JEDIYoda

Lifer
Jul 13, 2005
33,834
3,214
126
I'd like to know more about carbon filtration for an air purifier.

From what I read so far they can be as a foam like material, carbon pellets and a hybrid with a hepa filter.

Does more carbon result in better performance or just slower saturation?

How to those filters that have just a foam carbon filters compare with a hepa/carbon hybrid?

Thank you.
Google is your friend!!
 

noob25002

Member
Sep 16, 2018
73
2
41
Because you seem too stupid to actually google it...



(yes, they're trying to sell you their product)




(yes, they're also trying to sell you their coconut carbon product...for good reason. Coconut carbon is the most effective and efficient type for removing things like VOC's.)
First of all watch your mouth. I didn't post here to be verbally abused, understand?

Secondly, as for JEDIYoda, if you look at a lot of articles on the internet they say activated carbon filters do remove voc's. If your argument is that some of these are marketing, I could say the same for the article you posted, since it directs readers to a brand of purifier (with a link) mentioned at the end of the article.
 

Captante

Lifer
Oct 20, 2003
21,017
3,660
126
Nice try, SaltyNuts. You can't filter your muriatic acid fumes through a carbon filter and expect to breathe in the vapors... or can you?

Oh he ABSOLUTELY CAN do this .... most likely only once though! :p



First of all watch your mouth. I didn't post here to be verbally abused, understand?
Why? What's it going to do?!? :p

Uhhh oh! :eek::rolleyes:

waaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa.....

:D




Perhaps Romper-room.com is more your speed. ;)
 
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IronWing

No Lifer
Jul 20, 2001
63,437
17,096
136
Activated carbon should provide no benefit in removing particulates with the possible exception of the very smallest particles where surface charges might promote adhesion. Activated carbon should remove some types of VOCs but I'm skeptical that a system designed for home use would be of much value. Home systems are generally designed with aesthetics, noise, and profit margins in mind and allow too much air to bypass the filter.
 
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