# Bulk carbon



## marilynmonroe (Jan 8, 2009)

just looking for a good deal on bulk carbon :laugh:


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## No0dles (Dec 16, 2003)

ebay! http://cgi.ebay.com/5-Gal-Activated-Carbon...1742.m153.l1262

dont ask how i know but i've bought a few 10G from him it's way cheaper than buying anywhere else and it's good quality just make sure you rinse it before use!

he's got various sizes too his store name is carbon-eze check him out


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## CLUSTER ONE (Aug 2, 2006)

I think big als may sell a litre of carbon or something in bulk


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## jman785 (May 8, 2005)

You can also try Bulk Reef Supply


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## marilynmonroe (Jan 8, 2009)

thanks guys for the replys


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## Piranha_man (Jan 29, 2005)

Whatcha gonna do with all that carbon?


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## No0dles (Dec 16, 2003)

Piranha_man said:


> Whatcha gonna do with all that carbon?


if i told you i'd have to kill you


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## Piranha_man (Jan 29, 2005)

I'm just wondering why use so much carbon... or any at all for that matter.


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## His Majesty (Apr 5, 2005)

i use carbon. something i always did from the time i set up my first aquarium.
i use it on both FW and SW
Pman carbon improves water clarity by removeing odors, heavy metals, discolorations, organic contaminants and pollutants.

and yea make sure you rinse before use


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## No0dles (Dec 16, 2003)

like i said if i told you why i needed 20lbs of carbon each year i'd really have to kill you! and that right there is already giving away too much


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## Piranha_man (Jan 29, 2005)

Trigger lover said:


> i use carbon. something i always did from the time i set up my first aquarium.
> i use it on both FW and SW
> Pman carbon improves water clarity by removeing odors, heavy metals, discolorations, organic contaminants and pollutants.
> 
> and yea make sure you rinse before use


I think the benefits of carbon are overrated.
Unless in an attempt to remove medicinal treatment from a tank, I really don't see the purpose.


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## No0dles (Dec 16, 2003)

carbon is great and it's not over rated you just gotta know how to use it!

Activated Carbons / Charcoals - The Rundown

by Richard M. Greenfield
First published in the (now closed) British Marine Aquarists Association Journal
Aquarticles

Using the word carbon to a group of aquarists is almost sure to start a lively debate between those who use carbon regularly with excellent results and the others who point out that it removes trace elements, inhibits the growth of algae and isn't necessary, and so on.

Why is there so much controversy surrounding the use of activated carbon? 
There are, I think, several factors which confuse the issue. One is that activated carbon is peculiar stuff - a kind of mystical material and many aquarists are uncertain about what it is or exactly how it works. Another is that most people do not realise that the term "activated carbon" is about as specific as the word "paint". There are many kinds of paint for many different applications, and you wouldn't expect interior latex wall paint to be entirely satisfactory for use on your car! Likewise, some activated carbons offered for aquarium use are not very well suited for that particular application. Finally, I regret to say, there are several products on the market labelled "activated carbon" which are indeed carbon (coal) but are not "activated carbon". They are completely useless as water purifiers. An aquarist using one of these mislabelled products is not likely to be favourably impressed by what he thinks is activated carbon. By covering the question asked most often about activated carbon we can perhaps shed some light on the subject. We will discuss what it is, what it does and doesn't do, the trace element question and other aspects of carbon filtration.

Why is activated carbon used in aquaria?
We are all aware that the aquarium livestock generates toxic ammonia, which is converted in steps to relatively harmless nitrate by bacteria living in the filter bed. There are, however, a number of other contaminants generated in small amounts by the life process which can, over a period of time build up to a high enough to affect the health of the inhabitants of the aquarium.
A slight yellow tinge to the water can indicate the presence of at least one such contaminant. The most important function of activated carbon is to remove these impurities before they reach levels high enough to cause distress or organ damage.
Activated carbon performs other important tasks in the aquarium as well, removing toxic dissolved gasses such as hydrogen sulphide and methane, which result from imperfect water circulation. It acts as a catalyst to quickly convert dissolved chlorine gas to relatively harmless hydrogen chloride. It provides crystal clear water by removing minute suspended solids and colloids - those particles too small to be trapped by filter floss. It helps defend aquarium life on some occasions of accidental introduction of toxic substances such as pesticides,paint fumes,cigarette fumes and the like.

What is Activated Carbon?
Activated carbon, also called activated charcoal, is more involved in your life than you might suspect. It is used in the preparation of many products we use every day; to remove those impurities that cause an objec­tionable colour, taste, odour or health hazard from drinking water, waste water, foods and beverages (i.e. making sugar white instead of brown); to control air pollution (gas masks); and to separate/purify products in the chemical and pharmaceutical industries. The term "activated carbon" covers a family of materials made from carbon which have the ability to attract and hold certain substances on the carbon surface. This ability is called "adsorption". The adsorption process is an example of what is termed "chemical filtration", where certain dissolved substances are removed from the water. Filter floss, on the other hand performs "mechanical filtration" by trapping solid particles suspended in the water.

The raw materials most commonly used to create the carbon are coal, peat, lignite, wood and nutshells. None of these raw materials is pure carbon, although anthracite coal comes close. They contain unwanted hydrogen and oxygen as well. Those components are driven off by heating the raw material in the absence of air to produce a "char" (wood produces charcoal). The char is then activated by exposure to an extremely hot gas, usually steam at about 1500 deg. F, which etches tiny passageways through each carbon particle. The raw material selected, plus the manner in which it is activated, determines the characteristics of the finished activated carbon product and its cost. There are dozens of different kinds of activated carbon produced. Of these, only a handful will be well suited to any particular application.

Conversely, no one carbon will do well in all applications. For this reason, it is impossible to grade carbons, and terms such as "laboratory grade", "research grade", "premium grade" and the like do not exist in the activated carbon industry. Such terms are invented by the manufacturers in the aquarium trade to suggest, or imply quality, because the real clue to a carbon's suitability for aquarium use - the specification sheet - would be unintelligible to most aquarists. In discussing the following questions though we will cover many of the items that are found on a spec.sheet.

How does activated carbon work?
A particle of activated carbon is mostly air. It has thousands of tiny holes and crevices through which water can circulate. When water carries an organic molecule - a contaminant - into these narrow passages a short range attractive force between the molecule and the carbon will become effective and the molecule sticks. This particular method is called physical adsorption. The other kinds of adsorption also involved with activated carbon are of only minor importance to the aquarium.

What type of activated carbon is best for aquaria?
The effectiveness of an activated carbon for aquarium water purification depends on several factors which include total available surface area, pore size distribution, pore volume and particle size:

Surface area. Carbons having more surface area for impurities to stick to will obviously hold more impurities. Interestingly enough, virtually all the useful surface area in activated carbon is along the interior pores and not on what we think of as the outer surface has a negligible surface area because it is not porous, and has no measurable adsorptive capacity.
(Although it can provide mechanical filtration, ordinary coal does not remove dissolved contaminants.)
Wood charcoal is primarily a mechanical filtration medium with a slight adsorptive capability. Higher on the surface area scale are the bone chars made from animal bones, and other surface activated carbons. These, as the name implies, have an active outer surface covering an inactive carbon or phosphate core. Highest in surface area are the totally activated carbons. These are porous throughout the carbon particle and a total area can range upward to approx. 1,000 sq. m per gram (300,000 sq. ft per ounce). Surface area is a spec sheet item and is always expressed in square metres per gram. For aquarium use, more surface area is not necessarily better, because extremely high surface area implies a preponderance of extremely small holes or pores, too small for some of the larger molecule contaminants that we want to remove. Look for surface area figures in the 500-900 sq. m/gm range.

Pore size distribution. Pore sizes in activated carbon are classified as micropores, transitional pores and macropores (i.e. small, medium and large pores). Small size pores are limited to the adsorption of small molecules, medium pores concentrate the larger organic molecules typical of many aquarium contaminants. Larger pores provide easy water access to the interior of the carbon grain, resist clogging, and also perform a mechanical filtration function by trapping minute suspended solids to improve water clarity.
Most activated carbons have too much small pore and not enough medium pore capacity to be really effective for aquarium use. What happens is that the carbon becomes saturated with large molecule contaminants in a relatively short time while still retaining lots of unused space for small molecules. A good clue to favourable pore size distribution is a spec sheet figure called pore volume.

Pore volume. The combination of a relatively high percentage of medium and large pores plus a high surface area results in a carbon which has a high pore volume - lots of empty space inside the particle. A good pore volume figure would be 1 to 1.5 cc (or millilitres) per gram. High pore volume carbons appear to weigh less - to have a lower apparent density - than other carbons made from the same raw materials.

Particle size. The smaller the carbon particle, the shorter the water travel distance to the interior surfaces. There are several advantages to be obtained from using smaller particles. The activated carbon works faster, remaining effective in the modern outside filters, where the water flow rate is much faster than the rate considered ideal for carbon filtration. Useful lifetime is improved with small particles since they are Less likely to clog on the outside before all available adsorption sites are occupied on the interior surfaces. Particle size is indicated on a specification sheet by a notation such as "4 x 12 screen size", meaning that the product contains all those sizes which will fall through a screen having four wires per inch and not fall through a screen with 12 wires per inch, giving a size range of approx. 1/4 to 1/12 inch. (The gravel industry uses the same system, as in "6-20 silica".)

Economy. Totally activated carbon is the kind recommended for main aquaria, and it is (naturally) the most expensive form of aquarium carbon. On the other hand, it is by far the most economical kind to use when measured on a basis of cost per month of water purification service. A little goes a long way. It has 5-10 times more capacity than bone char and 50-60 times more than charcoal, yet it costs about 2-4 times more.

Activated Carbon Article #2:

Activated Carbon
Filter medium extraordinary

by Bob Straughan
From the Calypso Fish & Aquaria Club, London, England
Aquarticles

Activated carbon gets the water so clear that fish seem suspended in space! This was one of my early statements on this fantastic filtering medium, and decades later I am even more enthusiastic about the fabulous filtering qualities of activated carbon. In my opinion it is without equal in the aquarium field, and to do without it is to do without a sparkling clean aquarium where the water becomes invisible and the living jewels of the sea sparkle in water that is not only scrupulously clear but chemically and biologically clean. What more could be asked of a filtering medium?

Yet activated carbon is not well understood in the aquarium field - particularly in the salt water world. Improperly used, it can wipe out a tank of expensive fish overnight. Properly used, it can keep a tank full of fish in healthy condition for years without a single change of water. In fact, with the advent of the all glass tanks, a good undergravel filter with silica sand and a good outside filter that reaches all the way to the bottom with the siphon stem, it appears possible that a salt water aquarium could remain healthy and in good condition for a period of ten years without a single water change, provided, of course, activated carbon is used properly in the filter and good aquarium maintenance is observed at all times. Therein lies the solution to the successful use of activated carbon in the aquarium. You must know what you are doing! Otherwise you will have little or no success with the carbon.

Success with activated carbon depends upon several factors chiefly of which is the carbon itself. Like everything else, there is a great difference in carbons. Some are very cheap, others costly. Some are made of animal bones, wood, and various other materials. We use a product made from coconut shell, which we feel is consistently more pure and chemically inert than other products. It may or may not be the best, but I personally have tested it over many years in well over a thousand salt water aquariums under all types of conditions. It does the job and does it well, which is good enough for me. Until I find a product that works better, I am well satisfied with it. I have tried other brands of carbon of course. Some worked good; others were lethal.

Activated carbon is a powerful filtering agent. They used it in cigarettes, space ships, and deep sea submarines. It removes practically everything from the air, and in our instance, from the water. Because of its ability to extract gases, odours, fumes, etc., from the air, it can pick up poisonous substances from the air simply by being stored near them. In the case of chemical houses or pet stores, an opened case of carbon can absorb lethal doses of insecticides, paints, and dangerous chemicals, which could eventually cause problems in the aquarium. This sometimes causes unexplained failures with carbon when used in the aquarium. It also points out that activated carbon should be handled and stored with great care in air tight bags, especially if it is stored in a room with highly volatile substances. Otherwise it will be contaminated and unfit for use.

As pointed out above, there are many grades of carbon. Choose a known brand and one that is used by your local dealer if he is using it, or order a good quality carbon. The better grades of carbon will vary in price per pound, depending upon whether it is cured or fresh. At the higher price it seems expensive, but it will last a long while. Contrary to popular opinion, carbon does not lose its efficiency after a few hours in the aquarium. Quite to the contrary, it improves vastly with age! Well aged carbon is completely safe to use, for it is neutralised by its constant use. It can be used over and over again, even for years if it is not contaminated with oils or dangerous chemicals. Those who would state that carbon is not an effective filtering medium should try it sometime. I don't know where they obtained their information, but it's a fact that carbon five years old will turn a dull, dingy, brown colored aquarium into a thing of sparkling clean water as clear as distilled gin. Well, perhaps it's not the carbon that gets the water clean when you place it in the filter. It must be the spirit from the great beyond! Or perhaps these people don't know what they are talking about. I'm inclined to believe the latter.

The safest way to use activated carbon is to cure it in salt water for a few weeks before placing it in the filter. Then rinse it well in fresh water. It is best to start it in the filter when the tank is first set up and the fish have not yet been added. Let the filter operate for a week or two with the water, and then add the fish, floating them in a container and introducing them gradually to the aquarium. Carbon filtered water is different from unfiltered water. Salt water fish cannot take ANY sudden change from one type of water to another. The same is true when they are being introduced to a carbon filtered tank or when their aquarium is to have carbon added to it for the first time. It must be done very gradually so that the fish can slowly become adjusted to it. If a tank has been set up for several months, the sudden use of carbon can prove disastrous. In this case, a small amount of carbon, say a teaspoonful to a tablespoonful, should be added to the empty filter once or twice a week, gradually building up the carbon until the filter is full. But the carbon should be aged before use. This is most important.

Many people write inquiring whether or not glass wool or nylon, should be used in conjunction with the carbon. This is a matter of choice. If you have a good filter, you can use just the carbon, but if the filter has wide slots in the bottom, a little nylon or orlon will keep the car­bon from passing through the slots. We don't recommend glass wool, as the synthetic floss is safer to use in the aquarium and easier to handle besides. A little of it placed above the carbon will help trap additional dirt and is easily removed when dirty, which will help keep the carbon clean longer.

We also get many inquires about resins for keeping the water clean. To date, we have not seen any resins that would keep the aquarium water clean, and we have tried some of them. The only time we recommend them is when aquarium water needs softening, in which case they probably do help.

We have used the activated carbon all by itself with nothing added to it for most of our experiments, and the results have been phenomenal to say the least. It will get the water unbelievably clear arid keep the fish in perfect condition. We have even reclaimed chemically coloured water almost the colour of coffee, which was discoloured by adding copper sulphate and sulfathiazole sodium to the same tank for disease control. We had to change the carbon a couple of times, but it did the job. It got the water so clear you couldn't see it, and the water was perfectly healthy even though it was nearly two years old! We put in a large variety of both Atlantic and Pacific fish and they flourished in the peak of health and splendour.

Activated carbon can't do everything. It can't cure a sick fish. It can't keep an aquarium clean if you aren't using enough of it or if you overfeed or put some bad coral in the tank. Everything has its limitations. But if you use it correctly, a half pound to a pound for ten gallons depending upon other filtration, number of specimens, etc., and use it in a good filter so it can do its job proper]y, it will give you the cleanest water you have ever seen. You'll have to wash it when it gets dirty and dry it in the sun every now and then, but this is a small task and takes but a few minutes.

Use good carbon and use enough to do the job. Your reward will be the cleanest water you can imagine, as clear and sparkling as a mountain spring. The colours of your fish will be pure poetry.


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## Piranha_man (Jan 29, 2005)

Dude, that is an insanely long read...
I skimmed it though...

Good article!


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## No0dles (Dec 16, 2003)

it's info, knowledge is power brotha'


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## His Majesty (Apr 5, 2005)

No0dles said:


> it's info, knowledge is power brotha'


thats what my dad says all the time. although he doesn't say the brotha bit :laugh: 
and its totally true
although how do you come across so many good articled noodles?
do you just literally trawl through the internet and find them?


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## No0dles (Dec 16, 2003)

Trigger lover said:


> it's info, knowledge is power brotha'


thats what my dad says all the time. although he doesn't say the brotha bit :laugh: 
and its totally true
although how do you come across so many good articled noodles?
do you just literally trawl through the internet and find them?
[/quote]

i got a thing for info that im interested in! when i wanna learn about something it comes with passion and like i said the more i know the more power i got! yes i get a LOT off the internet but not everything you read is true especially on the internet so you have to do A LOT of reading and find out which is worthy and which information is just total BS...it requires a lot of reading and taking everything in with an open mind. im the type of person that likes to find out things for himself and ask as little questions as i can without doing my own ton of research then by the time im researched out and still have questions i will ask! and for the most part when you look into stuff with great detail and do lots of research the less questions you'll have that haven't ever been answered before!


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## His Majesty (Apr 5, 2005)

definetly a good way of going about it.
i actually prefer hearing different people opinions and their own knowledge. gives you another perspective and it helps with judging whats good information and whats tripe.
i agree interent is full of sh*t at times. i get alot of my own info from reading books and articles. the old fashioned way. i find it better than staring at a screen reading lots of info. plus with articles and books you can see how information and technology has developed and how peoples thinking has changed over time. you wont believe some of the older books on fish keeping. sometimes its frightening what people did and thought was best. not just in fish keeping but in all aspects of life. oh how we have come a long way. but in some respects we have no moved forward at all.


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## No0dles (Dec 16, 2003)

that's with anything though when something becomes more advanced your always gonna look back and be like, damn are you serious? haha it's just what worked best at the time with the amount of knowledge people had...


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## Death in #'s (Apr 29, 2003)

dam that was along but awesome read

thnx for that


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## blbig50 (Jan 1, 2009)

Well, my question is, how would you use carbon with a HOB filter?


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## rchan11 (May 6, 2004)

I bought mine bulk carbon at Walmart.


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## Plum (May 4, 2006)

came across this thread and want to know if anyone else has heard more about this "carbon cleaning". To date, I have not heard of this, though with ZEOLITE products, and other filtration systems, a "salt bath" is used to essentially recharge the product.

Any knowledgable commentary is appreciated, I will also investigate the matter .


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## No0dles (Dec 16, 2003)

there's lots of different types of carbon etc. and a few ways to regenerate but i personally wouldn't bother. i've heard of people throwing them in the shower, washing it, and then throwing it in their ovens at the highest temp it could go but that's still not enough haha so they FAIL! anyways, here's a wiki on it which is pretty accurate from what i know about types of carbon:

Activated carbon
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Activated carbon
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Activated carbon, also called activated charcoal or activated coal, is a form of carbon that has been processed to make it extremely porous and thus to have a very large surface area available for adsorption or chemical reactions. [1] The word activated in the name is sometimes substituted by active. Due to its high degree of microporosity, just one gram of activated carbon has a surface area of approximately 500 m² (or about 2.17 tennis courts), as determined typically by nitrogen gas adsorption. Sufficient activation for useful applications may come solely from the high surface area, though further chemical treatment often enhances the adsorbing properties of the material. Activated carbon is usually derived from charcoal.
Contents
[hide]

* 1 Production
* 2 Properties
* 3 Classifications
o 3.1 Powdered activated carbon (PAC)
o 3.2 Granular activated carbon (GAC)
o 3.3 Extruded activated carbon (EAC)
o 3.4 Impregnated carbon
o 3.5 Polymers coated carbon
o 3.6 Other
* 4 Properties of activated carbon
o 4.1 Iodine Number
o 4.2 Molasses
o 4.3 Tannin
o 4.4 Methylene blue
o 4.5 Dechlorination
o 4.6 Apparent density
o 4.7 Hardness/abrasion number
o 4.8 Ash content
o 4.9 Carbon tetrachloride activity
o 4.10 Particle size distribution
* 5 Examples of adsorption
o 5.1 Heterogeneous catalysis
o 5.2 Adsorption refrigeration
* 6 Applications
o 6.1 Environmental applications
o 6.2 Medical applications
o 6.3 Gas purification
o 6.4 Distilled alcoholic beverage purification
* 7 Mercury scrubbing
o 7.1 Disposal in the USA
* 8 See also
* 9 External links
* 10 References

[edit] Production

Activated carbon is produced from carbonaceous source materials like nutshells, wood and coal. It can be produced by one of the following processes:

1. Physical reactivation: The precursor is developed into activated carbons using gases. This is generally done by using one or a combination of the following processes:
* Carbonization: Material with carbon content is pyrolyzed at temperatures in the range 600-900 °C, in absence of air (usually in inert atmosphere with gases like argon or nitrogen)
* Activation/Oxidation: Raw material or carbonised material is exposed to oxidizing atmospheres (carbon dioxide, oxygen, or steam) at temperatures above 250 °C, usually in the temperature range of 600-1200 °C.
2. Chemical activation: Impregnation with chemicals such as acids like phosphoric acid or bases like potassium hydroxide, sodium hydroxide or salts like zinc chloride, followed by carbonization at temperatures in the range of 450-900 °C. It is believed that the carbonization / activation step proceeds simultaneously with the chemical activation. This technique can be problematic in some cases, because, for example, zinc trace residues may remain in the end product. However, chemical activation is preferred over physical activation owing to the lower temperatures and shorter time needed for activating material.

[edit] Properties

A gram of activated carbon can have a surface area in excess of 500 m², with 1500 m² being readily achievable. Carbon aerogels, while more expensive, have even higher surface areas, and are used in special applications.

Under an electron microscope, the high surface-area structures of activated carbon are revealed. Individual particles are intensely convoluted and display various kinds of porosity; there may be many areas where flat surfaces of graphite-like material run parallel to each other, separated by only a few nanometers or so. These micropores provide superb conditions for adsorption to occur, since adsorbing material can interact with many surfaces simultaneously. Tests of adsorption behaviour are usually done with nitrogen gas at 77 K under high vacuum, but in everyday terms activated carbon is perfectly capable of producing the equivalent, by adsorption from its environment, liquid water from steam at 100 °C and a pressure of 1/10,000 of an atmosphere.

Physically, activated carbon binds materials by Van der Waals force or London dispersion force.

Activated carbon does not bind well to certain chemicals, including alcohols, glycols, ammonia, strong acids and bases, metals and most inorganics, such as lithium, sodium, iron, lead, arsenic, fluorine, and boric acid. Activated carbon does adsorb iodine very well and in fact the iodine number, mg/g, (ASTM D28 Standard Method test) is used as an indication of total surface area.

Activated carbon can be used as a substrate for the application of various chemicals to improve the adsorptive capacity for some inorganic (and problematic organic) compounds such as hydrogen sulfide (H2S), ammonia (NH3), formaldehyde (HCOH), radioisotopes iodine-131 (131I) and mercury (Hg). This property is known as chemisorption.

[edit] Classifications

Activated carbons are complex products which are difficult to classify on the basis of their behaviour, surface characteristics and preparation methods. However, some broad classification is made for general purpose based on their physical characteristics.

[edit] Powdered activated carbon (PAC)

Traditionally, active carbons are made in particular form as powders or fine granules less than 1.0 mm in size with an average diameter between .15 and .25 mm.[citation needed] Thus they present a large surface to volume ratio with a small diffusion distance. PAC is made up of crushed or ground carbon particles, 95-100% of which will pass through a designated mesh sieve or sieve. Granular activated carbon is defined as the activated carbon being retained on a 50-mesh sieve (0.297 mm) and PAC material as finer material, while ASTM classifies particle sizes corresponding to an 80-mesh sieve (0.177 mm) and smaller as PAC. PAC is not commonly used in a dedicated vessel, owing to the high headloss that would occur. PAC is generally added directly to other process units, such as raw water intakes, rapid mix basins, clarifiers, and gravity filters.

[edit] Granular activated carbon (GAC)

Granular activated carbon has a relatively larger particle size compared to powdered activated carbon and consequently, presents a smaller external surface. Diffusion of the adsorbate is thus an important factor. These carbons are therefore preferred for all adsorption of gases and vapours as their rate of diffusion are faster. Granulated carbons are used for water treatment, deodourisation and separation of components of flow system. GAC can be either in the granular form or extruded. GAC is designated by sizes such as 8x20, 20x40, or 8x30 for liquid phase applications and 4x6, 4x8 or 4x10 for vapour phase applications. A 20x40 carbon is made of particles that will pass through a U.S. Standard Mesh Size No. 20 sieve (0.84 mm) (generally specified as 85% passing) but be retained on a U.S. Standard Mesh Size No. 40 sieve (0.42 mm) (generally specified as 95% retained). AWWA (1992) B604 uses the 50-mesh sieve (0.297 mm) as the minimum GAC size. The most popular aqueous phase carbons are the 12x40 and 8x30 sizes because they have a good balance of size, surface area, and headloss characteristics.

[edit] Extruded activated carbon (EAC)

Consists of extruded and cylindrical shaped activated carbon with diameters from 0.8 to 45 mm. These are mainly used for gas phase applications because of their low pressure drop, high mechanical strength and low dust content.

[edit] Impregnated carbon

Porous carbons containing several types of inorganic impregnant such as iodine, silver, cation such as Al, Mn, Zn, Fe, Li, Ca have also been prepared for specific application in air pollution control especially in museums and galleries. Due to antimicrobial/antiseptic properties, silver loaded activated carbon is used as an adsorbent for purifications of domestic water. Drinking water can be obtained from natural water by treating the natural water with a mixture of activated carbon and flocculating agent Al(OH)3. Impregnated carbons are also used for the adsorption of H2S and mercaptans. Adsorption rates for H2S as high as 50% by weight have been reported.

[edit] Polymers coated carbon

This is a process by which a porous carbon can be coated with a biocompatible polymer to give a smooth and permeable coat without blocking the pores. The resulting carbon is useful for hemoperfusion. Hemoperfusion is a treatment technique in which large volumes of the patient's blood are passed over an adsorbent substance in order to remove toxic substances from the blood.

[edit] Other

Activated carbon is also available in special forms such as cloths and fibres. The "Carbon cloth" for instance is used in personnel protection for the military.

[edit] Properties of activated carbon

[edit] Iodine Number

Many carbons preferentially adsorb small molecules. Iodine number is the most fundamental parameter used to characterize activated carbon performance. It is a measure of activity level (higher number indicates higher degree of activation), often reported in mg/g (typical range 500-1200 mg/g). It is a measure of the micropore content of the activated carbon (0 to 20 Å, or up to 2 nm) by adsorption of iodine from solution. It is equivalent to surface area of activated carbon between 900 m²/g and 1100 m²/g. It is the standard measure for liquid phase applications.

Iodine number is defined as the milligrams of iodine adsorbed by one gram of carbon when the iodine concentration in the residual filtrate is 0.02 normal. Basically, iodine number is a measure of the iodine adsorbed in the pores and, as such, is an indication of the pore volume available in the activated carbon of interest. Typically, water treatment carbons have iodine numbers ranging from 600 to 1100. Frequently, this parameter is used to determine the degree of exhaustion of a carbon in use. However, this practice should be viewed with caution as chemical interactions with the adsorbate may affect the iodine uptake giving false results. Thus, the use of iodine number as a measure of the degree of exhaustion of a carbon bed can only be recommended if it has been shown to be free of chemical interactions with adsorbates and if an experimental correlation between iodine number and the degree of exhaustion has been determined for the particular application.

[edit] Molasses

Some carbons are more adept at adsorbing large molecules. Molasses number or molasses efficiency is a measure of the mesopore content of the activated carbon (greater than 20 Å, or larger than 2 nm) by adsorption of molasses from solution. A high molasses number indicates a high adsorption of big molecules (range 95-600). Caramel dp (decolorizing performance) is similar to molasses number. Molasses efficiency is reported as a percentage (range 40%-185%) and parallels molasses number (600 = 185%, 425 = 85%). The European molasses number (range 525-110) is inversely related to the North American molasses number.

Molasses Number is a measure of the degree of decolorization of a standard molasses solution that has been dilited and standardized against standardized activated carbon. Due to the size of color bodies, the molasses number represents the potential pore volume available for larger adsorbing species. As all of the pore volume may not be available for adsorption in a particular waste water application, and as some of the adsorbate may enter smaller pores, it is not a good measure of the worth of a particular activated carbon for a specific application. Frequently, this parameter is useful in evaluating a series of active carbons for their rates of adsorption. Given two active carbons with similar pore volumes for adsorption, the one having the higher molasses number will usually have larger feeder pores resulting in more efficient transfer of adsorbate into the adsorption space.

[edit] Tannin

Tannins are a mixture of large and medium size molecules. Carbons with a combination of macropores and mesopores adsorb tannins. The ability of a carbon to adsorb tannins is reported in parts per million concentration (range 200 ppm-362 ppm).

[edit] Methylene blue

Some carbons have a mesopore (20 Å to 50 Å, or 2 to 5 nm) structure which adsorbs medium size molecules, such as the dye methylene blue. Methylene blue adsorption is reported in g/100g (range 11-28 g/100g).

[edit] Dechlorination

Some carbons are evaluated based on the dechlorination half-value length, which measures the chlorine-removal efficiency of activated carbon. The dechlorination half-value length is the depth of carbon required to reduce the chlorine level of a flowing stream from 5 ppm to 3.5 ppm. A lower half-value length indicates superior performance.

[edit] Apparent density

Higher density provides greater volume activity and normally indicates better quality activated carbon.

[edit] Hardness/abrasion number

It is a measure of the activated carbon's resistance to attrition. It is important indicator of activated carbon to maintain its physical integrity and withstand frictional forces imposed by backwashing, etc. There are large differences in the hardness of activated carbons, depending on the raw material and activity level.

[edit] Ash content

It reduces the overall activity of activated carbon. It reduces the efficiency of reactivation. The metals (Fe2O3) can leach out of activated carbon resulting in discoloration. Acid/water soluble ash content is more significant than total ash content. Soluble ash content can be very important for aquarists, as ferric oxide can promote algal growths, a carbon with a low soluble ash content should be used for marine, freshwater fish and reef tanks to avoid heavy metal poisoning and excess plant/algal growth.

[edit] Carbon tetrachloride activity

Measurement of the porosity of an activated carbon by the adsorption of saturated carbon tetrachloride vapour.

[edit] Particle size distribution

The finer the particle size of an activated carbon, the better the access to the surface area and the faster the rate of adsorption kinetics. In vapour phase systems this needs to be considered against pressure drop, which will affect energy cost. Careful consideration of particle size distribution can provide significant operating benefits.

[edit] Examples of adsorption

[edit] Heterogeneous catalysis

The most commonly encountered form of chemisorption in industry, occurs when a solid catalyst interacts with a gaseous feedstock, the reactant/s. The adsorption of reactant/s to the catalyst surface creates a chemical bond, altering the electron density around the reactant molecule and allowing it to undergo reactions that would not normally be available to it.

[edit] Adsorption refrigeration

Adsorption refrigeration and heat pump cycles rely on the adsorption of a refrigerant gas into an adsorbent at low pressure and subsequent desorption by heating. The adsorbent acts as a "chemical compressor" driven by heat and is, from this point of view, the "pump" of the system. It consists of a solar collector, a condenser or heat-exchanger and an evaporator that is placed in a refrigerator box. The inside of the collector is lined with an adsorption bed packed with activated carbon adsorbed with methanol. The refrigerator box is insulated filled with water. The activated carbon can adsorb a large amount of methanol vapours in ambient temperature and desorb it at a higher temperature (around 100 degrees Celsius). During the daytime, the sunshine irradiates the collector, so the collector is heated up and the methanol is desorbed from the activated carbon. In desorption, the liquid methanol adsorbed in the charcoal heats up and vaporizes. The methanol vapour condenses and is stored in the evaporator.

At night, the collector temperature decreases to the ambient temperature, and the charcoal adsorbs the methanol from the evaporator. The liquid methanol in the evaporator vaporizes and absorbs the heat from the water contained in the trays. Since adsorption is a process of releasing heat, the collector must be cooled efficiently at night. As mentioned above, the adsorption refrigeration system operates in an intermittent way to produce the refrigerating effect.

Helium gas can also be 'pumped' by thermally cycling activated carbon 'sorption pumps' between 4 kelvins and higher temperatures. An example of this is to provide the cooling power for the Oxford Instruments AST series dilution refrigerators. 3He vapour is pumped from the surface of the dilute phase of a mixture of liquid 4He and its isotope 3He. The 3He is adsorbed onto the surfaces of the carbon at low temperature (typically <4K), the regeneration of the pump between 20 and 40 K returns the 3He to the concentrated phase of the liquid mixture. Cooling occurs at the interface between the two liquid phases as 3He 'evaporates' across the phase boundary. If more than one pump is present in the system a continuous flow of gas and hence constant cooling power can be obtained, by having one sorption pump regenerating while the other is pumping. Systems such as this allow temperatures as low as 10 mK (0.01 kelvin) to be obtained with very few moving parts.

[edit] Applications

Activated carbon is used in gas purification, gold purification, metal extraction, water purification, medicine, sewage treatment, air filters in gas masks and filter masks, filters in compressed air and many other applications.

One major industrial application involves use of activated carbon in metal finishing field. It is very widely employed for purification of electroplating solutions. For example, it is a main purification technique for removing organic impurities from bright nickel plating solutions. A variety of organic chemicals are added to plating solutions for improving their deposit qualities and for enhancing properties like brightness, smoothness, ductility, etc. Due to passage of direct current and electrolytic reactions of anodic oxidation and cathodic reduction, organic additives generate unwanted break down products in solution. Their excessive build up can adversely affect the plating quality and physical properties of deposited metal. Activated carbon treatment removes such impurities and restores plating performance to the desired level.

[edit] Environmental applications

Carbon adsorption has numerous applications in removing pollutants from air or water streams both in the field and in industrial processes such as:

* Spill cleanup
* Groundwater remediation
* Drinking water filtration
* Air purification
* Volatile organic compounds capture from painting, dry cleaning, gasoline dispensing operations, and other processes.

In 2007 University college West-Flanders HOWEST (Belgium) started the research after water treatment on festivals. The result was a fullscale activated carbon installation, applicated at the Dranouter music festival in 2008. The next 20 years the water of this festival will be treated with this technology.

Activated charcoal is also used for the measurement of radon concentration in air.

[edit] Medical applications

Activated carbon is used to treat poisonings and overdoses following oral ingestion.

It is thought to bind to poison and prevent its absorption by the gastrointestinal tract. In cases of suspected poisoning, medical personnel administer activated charcoal on the scene or at a hospital's emergency department. Dosing is usually empirical at 1 gram/kg of body weight ( for adolescents or adults, give 50-100 g ), usually given only once, but depending on the drug taken, it may be given more than once. In rare situations activated charcoal is used in Intensive Care to filter out harmful drugs from the blood stream of poisoned patients. Activated carbon has become the treatment of choice for many poisonings, and other decontamination methods such as ipecac-induced emesis or stomach pumps are now used rarely.

While activated carbon is useful in an acute poisoning situation, it has been shown to not be effective in long term accumulation of toxins, such as with the use of toxic herbicides.[2]

Mechanisms of action:

* Binding of the toxin to prevent stomach and intestinal absorption. Binding is reversible so a cathartic such as sorbitol may be added as well.
* It interrupts the enterohepatic circulation of some drugs/toxins and their metabolites

Incorrect application (e.g. into the lungs) results in pulmonary aspiration which can sometimes be fatal if immediate medical treatment is not initiated.[3] The use of activated charcoal is contraindicated when the ingested substance is an acid, an alkali, or a petroleum product.

For pre-hospital use, it comes in plastic tubes or bottles, commonly 12.5 or 25 grams, pre-mixed with water. The trade names include InstaChar, SuperChar, Actidose, and Liqui-Char, but it is commonly called simply Activated Charcoal.

Ingestion of activated carbon prior to consumption of ethanol has been shown to reduce absorption of alcohol into the blood. 5 to 15 milligrams of charcoal per kilogram of body weight taken at the same time as 170 ml of pure ethanol (which equals about 10 servings of an alcoholic beverage alcohol, or 17 shots), over the course of one hour, has very apparent effects at reducing potential blood alcohol content[4]

In the past charcoal biscuit was sold in England in the early 19th century, originally as an antidote to flatulence and stomach trouble.[5]

Tablets of activated charcoal are still used as a folk remedy and over-the-counter drug to treat diarrhea, indigestion, and flatulence.[6] They were also used in the past by doctors for this purpose. There is some evidence of its effectiveness as a treatment for irritable bowel syndrome (IBS),[7] and to prevent diarrhea in cancer patients who have received irinotecan.[8] It can interfere with the absorbency of some medications, and lead to unreliable readings in medical tests such as the guaiac card test.[9] A type of charcoal biscuit has been marketed as a pet care product.

Activated charcoal is also used for bowel preparation by reducing intestinal gas content before abdominal radiography to visualize bile, pancreatic and renal stones.

[edit] Gas purification

Filters with activated carbon are usually used in compressed air and gas purification to remove oil vapours, odours, and other hydrocarbons from the air. The most common designs use a 1 stage or 2 stage filtration principle in which activated carbon is embedded inside the filter media. Activated charcoal is also used in spacesuit Primary Life Support Systems. Activated charcoal filters are used to retain radioactive gases from a nuclear boiling water reactor turbine condenser. The air vacuumed from the condenser contains traces of radioactive gases. The large charcoal beds adsorb these gases and retains them while they rapidly decay to non-radioactive solid species. The solids are trapped in the charcoal particles, while the filtered air passes through.

[edit] Distilled alcoholic beverage purification
See also: Lincoln County Process

Activated carbon filters can be used to filter vodka and whiskey of organic impurities which can affect color, taste, and odor. Passing an organically impure vodka through an activated carbon filter at the proper flow rate will result in vodka with an identical alcohol content and significantly increased organic purity, as judged by odor and taste.[citation needed]

[edit] Mercury scrubbing

Activated carbon, often impregnated with iodine or sulfur, is widely used to trap mercury emissions from coal fired power stations, medical incinerators, and from natural gas at the wellhead. This carbon is a specialty product costing more than $4.00 per kg. However, it is often not recycled.

[edit] Disposal in the USA

The mercury laden activated carbon presents a disposal dilemma.[citation needed] If the activated carbon contains less than 260 ppm mercury, Federal regulations allow it to be stabilized (for example, trapped in concrete) for landfilling.[citation needed] However, waste containing greater than 260 ppm is considered to be in the high mercury subcategory and is banned from landfilling (Land-Ban Rule).[citation needed] It is this material which is now accumulating in warehouses and in deep abandoned mines at an estimated rate of 1000 tons per year.[citation needed]

The problem of disposal of mercury laden activated carbon is not unique to the U.S. In the Netherlands this mercury is largely recovered[10] and the activated carbon is disposed by complete burning.

[edit] See also

* Carbon black
* Carbon filtering
* Zeocarbon
* Sumi
* Kværner-process

[edit] External links

* "Activated Carbon for water filtration" - Treatment Systems for Household Water Supplies] AE-1029, February 1992
* "Imaging the atomic structure of activated carbon" - JOURNAL OF PHYSICS: CONDENSED MATTER
* Engber, Daniel (Nov. 28, 2005). "How Does Activated Carbon Work?". Slate.

[edit] References

1. ^ "Properties of Activated Carbon", CPL Caron Link, accessed 2008-05-02
2. ^ Eddleston M, Juszczak E, Buckley NA, et al. (2008). "Multiple-dose activated charcoal in acute self-poisoning: a randomised controlled trial". Lancet 371 (9612): 579. doi:10.1016/S0140-6736(08)60270-6. 
3. ^ Elliott C, Colby T, Kelly T, Hicks H (1989). "Charcoal lung. Bronchiolitis obliterans after aspiration of activated charcoal". Chest 96 (3): 672-4. doi:10.1378/chest.96.3.672. PMID 2766830. 
4. ^ Procter, Richard & Stanton Anondson, "Method of altering intoxicating effects of alcohol", US 4594249, issued 1986
5. ^ Rolland, Jacques L. (2006). The Food Encyclopedia: Over 8,000 Ingredients, Tools, Techniques and People. Robert Rose. pp. 148. ISBN 0778801500. 
6. ^ Stearn, Margaret (2007). Warts and all: straight talking advice on life's embarrassing problems. London: Murdoch Books. p. 333. ISBN 978-1-92125984-5. http://books.google.co.uk/books?id=aSRmxC4...ontcover#PPA333. Retrieved on 2009-05-03. 
7. ^ Hübner WD, Moser EH (2002). "Charcoal tablets in the treatment of patients with irritable bowel syndrome". Adv Ther 19 (5): 245-52. doi:10.1007/BF02850364. PMID 12539884. https://www.advancesintherapy.com/detail.aspx?ID=276. 
8. ^ Michael M, Brittain M, Nagai J, et al. (Nov 2004). "Phase II study of activated charcoal to prevent irinotecan-induced diarrhea". J Clin Oncol. 22 (21): 4410-7. doi:10.1200/JCO.2004.11.125. PMID 15514383. 
9. ^ Gogel HK, Tandberg D, Strickland RG (Sep 1989). "Substances that interfere with guaiac card tests: implications for gastric aspirate testing". Am J Emerg Med 7 (5): 474-80. doi:10.1016/0735-6757(89)90248-9. PMID 2787993. 
10. ^ BMT-Begemann, Mercury waste treatment facilities

[hide]
v • d • e
Allotropes of carbon
sp3 forms 
Diamond (cubic) ♦ Lonsdaleite (hexagonal diamond)
sp2 forms 
Graphite ♦ Fullerenes (buckyballs (C20+)) ♦ Nanotubes ♦ Glassy carbon
sp forms 
Linear acetylenic carbon
mixed sp3/sp2 forms 
Amorphous carbon ♦ nanobuds ♦ Carbon nanofoam
other forms 
C1 - C2 - C3 - C8
related 
Chaoite - Activated carbon - Carbon black - Charcoal - Carbon fiber - Fullerite - Aggregated diamond nanorods


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## His Majesty (Apr 5, 2005)

holy crap noodles. lol im not reading through that. mainly because i cant be arsed and dont want to know that much about carbon

but good going on the research


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## Guest (Jun 12, 2009)

Trigger lover said:


> holy crap noodles. lol im not reading through that. mainly because i cant be arsed and dont want to know that much about carbon
> 
> but good going on the research










I concur, lol


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## Plum (May 4, 2006)

Nothing wrong with learning something....

Thank you for the post - it generally follows the same lines as the other things I have read.


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## Plum (May 4, 2006)

*In the past charcoal biscuit was sold in England in the early 19th century, originally as an antidote to flatulence and stomach trouble.[5]

Tablets of activated charcoal are still used as a folk remedy and over-the-counter drug to treat diarrhea, indigestion, and flatulence.[6] They were also used in the past by doctors for this purpose. There is some evidence of its effectiveness as a treatment for irritable bowel syndrome (IBS),[7] and to prevent diarrhea in cancer patients who have received irinotecan.[8] It can interfere with the absorbency of some medications, and lead to unreliable readings in medical tests such as the guaiac card test.[9] A type of charcoal biscuit has been marketed as a pet care product.

Activated charcoal is also used for bowel preparation by reducing intestinal gas content before abdominal radiography to visualize bile, pancreatic and renal stones.

*I have heard of this before, and the application I heard of it was with farmed fish/pigs. The reason the farmers were using it is for the purpose of the above, and they found increased health in their stock & also better growth rates. (actually read it here: http://www.piranha-fury.com/pfury/index.ph...bamboo+charcoal)

Not related, but interesting.


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## No0dles (Dec 16, 2003)

they also give you liquid







or powdered activated charcoal after they pump your stomach to soak up any poison that's in it! dont ask how i know but i know more than the average person when it comes to carbon haha


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