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Activated Carbon Turns Wine Into Water? Activated Carbon Filter Turning Wine Into Water. Below is a video of an activated carbon filter turning wine into water.

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The Activated Carbon Standard

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Posted on : 01-03-2012 | By : Mr. Green | In : Activated Carbon
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Carbon in Pulp Helps to Purify Gold

Gold is one of the most historically significant, valuable, and precious naturally occurring metals that exists here on Earth.  Its history with humans has been both beautiful and tumultuous:a lot of people personally choose to wear gold as rings or other jewelry to symbolize marriage or wealth, while wars have been started over lands that contain vast amounts of gold to mine.

Gold’s most significant part of human history may have been its use as a monetary policy that was called the Gold Standard, which was one of the most widespread forms of monetary policy until the  Flat Standard started to be implemented in the early 20th century.

Gold’s value as currency and as a form of jewelry requires gold to be pure and this is where the adsorbent activated carbon plays an important role.   Since freshly mined gold ore is rarely ever found in a purified form it must be purified, through a gold extraction process.  Although purifying gold had been done for centuries, beginning in the back half of the 20th century activated carbon began to be used to purify gold because of its strong adsorption capabilities.

Activated carbon is used in a gold extraction method called The Gold Cyanidation Process (which is sometimes referred as Gold Leaching).  Gold Cyanidation is currently the most commonly used gold extraction method.

Gold Cyanidation works by crushing ore with gold in it into small pieces.  Water is then added along with cyanide which breaks the gold down into a pulpy type of liquid.  After this is done the gold must be harvested from the cyanide solution.  Two processes are commonly used after the Gold Cyanidation Process, they are: The Carbon in Pulp Process (CIP) or The Carbon Column Process.

Both of these processes are very similar in that they use activated carbon to remove the gold from the leaching solution, however the equipment used is different.  Carbon in Pulp is used when gold leaching occurs in tank with activated carbon, while the Carbon Column Process removes gold in large stacked columns that are loaded with activated carbon.

Both processes work by utilizing activated carbon which is charged so it can specifically adsorb gold.  The gold from the leaching solution is adsorbed by the activated carbon in either the columns or the tanks, leaving behind the water and cyanide.

As activated carbon reaches its adsorption capacity it is removed and sent to a stripping circuit where it is heated to high temperatures and mixed with cyanide and sodium hydroxide.  After the gold is removed from the activated carbon the gold is placed in vessel where it is attached to steel cathodes where it is usually removed with a pressure water spray and placed in Dore bars.

Activated carbon can help to purify gold over 99% making its role in modern gold extraction very important.

 

Sources:

http://www.goldminded.com/carbon_in_pulp.html

http://mine-engineer.com/mining/minproc/carbon_ad.htm

http://www.e-goldprospecting.com/html/carbon_in_pulp_.html

http://www.responsiblegold.org/gold_production.asp

Stopping Poison with Activated Carbon

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Posted on : 27-10-2011 | By : Mr. Green | In : Activated Carbon, History
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Activated Carbon’s Historical Use of Being A Medicine

Activated carbon and charcoal (which is what is primarily used to make activated carbon) has been used medicinally for thousands of years.  Our previous article “Making Whiskey” mentions that Hippocrates the western father of modern medicine recorded using charcoal in some of his treatments.

Activated carbon has had its skeptics throughout history but chemist Pierre-Fleurus Touery put the critics to rest with his famous demonstration in the mid 19th century.  Touery’s demonstration which was performed in front of the French Academy of Medicine saw Touery ingest a dose of strychnine, that was ten times higher than what was required to be a lethal dose.

I believe it is important to mention that strychnine is a  poison that can cause some of the most painful symptoms a person can experience  by ingesting a toxic substance.  Strychnine is rumored to be the poison that killed Alexander the Great and its symptoms have been used to great dramatic effect by Hollywood with one of the more notable films being Alfred Hitchcock’s Psycho.  In Psycho Norman Bates kills his mother and her lover with strychnine.

Touery took 15 grams of activated carbon with the (mentioned above)  lethal dose of strychnine and stood there as time ticked away.  Nothing happened, and Touery’s shocked audience watched as Touery walked away from the event unharmed.  The end result: activated carbon had been proven that it could be used to stop the effects of poison on humans.

Activated carbon works by adsorbing all of the toxins onto its highly porous surface area.  (10 grams of Activated Carbon has enough surface area to cover an entire American football field).  In other words it doesn’t take a lot activated carbon to adsorb toxins.

The toxins once adsorbed remain on the activated carbon until it is passed through the digestive system and out of the body.  The toxins are bound so tight to the activated carbon that the stomach and intestines are not able to absorb them.

Today activated carbon is still used to treat people who have been poisoned.  It is often associated with treating alcohol overdoses but it has seen effective results in treating indigestion, heartburn, and some intestinal disorders.  Activated carbon is most often sold to consumers in capsules, tablets, supplements, and as activated charcoal.

It is important to remember that activated carbon does not effectively treat all poisons, but it can effectively treat many of them.  Activated carbon’s use as a medicine is just one of its many functions, we will be writing more about those functions in the near future.

Sources:

Who goes first?: The Story of Self-experimentation in Medicine, Author: Lawrence K. Altman

http://www.emedicinehealth.com/activated_charcoal/page2_em.htm

Desiccants at War!

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Posted on : 30-09-2011 | By : Mr. Green | In : Activated Carbon, History, Silica Gel, Zeolites
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A Look Into How Military’s Use Desiccants in Gas Masks and Medical Equipment

Desiccants are used all over the world and military’s around the world are no exception.

The first widespread use of desiccants by any military occurred during the First World War.  This war is famous for the use of chemical gases as a weapon, and armies that were afflicted with a barrage of gas containing shells needed protection in order to avoid being poisoned.

This led to the first gas masks being mass produced.  The material in the gas mask canisters that absorbed potential toxins was silica gel, and this helped to reduce the effects of poisonous gas attacks that opposing armies faced throughout the remainder of the war.

During 1915 ,while World War I was on-going, Russian scientist Nikolay Zelinsky improved upon the gas mask by creating a filter that used activated carbon, another desiccant.  Today activated carbon is the standard desiccant used in most modern gas masks.

The activated carbon filters in gas masks didn’t start getting used until after World War II.  During this war silica gel was replaced as the primary adsorbing material in gas mask by asbestos… which the world learned after the war caused serious illnesses like mesothelioma and malignant lung cancer.

This paved the way for modern gas masks which use activated carbon filters in combination with aerosol filters to keep soldiers safe.  Activated carbon has a larger surface area than silica gel and can adsorb more potentially dangerous airborne chemicals, thus making it more effective filter.

Besides being used in gas masks, desiccants have recently found a new use in military medical technology.

Zeolites have been attached to gauze and recently been used by the U.S. military to help reduce the blood flow in wounded soldiers and civilians.  The pores in the zeolites are small enough to adsorb the water out of the bloodstream leaving only cells and platelets.

Platelets circulate throughout our blood stream looking to clot blood.  With all the water absorbed out of the bloodstream, thanks to the zeolites, the blood is allowed to clot a lot faster.  This has helped save many lives because it greatly speeds up the time for a wound to close and stop bleeding and it also reduces the chance of wound becoming infected.

The success of zeolites in gauze has allowed this product to be used in the commercial medical market and it is now being used by law enforcement and emergency response units.

 

Introducing…Carbon Molecular Sieve

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What Is It and How Does It Separate Oxygen from Nitrogen

What is carbon molecular sieve?

Carbon molecular sieve is an adsorbent that fuses the ideas behind both activated carbon and zeolites into one product.  Activated carbon is known for its high porosity and zeolites are known for their ability to be crafted into highly specialized adsorbents called molecular sieve.  Carbon molecular sieve is a product that brings the benefits of both of these products together.

Carbon molecular sieve is made out of coal (the same material most activated carbon is made out of) and it specializes in adsorbing material under 10 angstroms, something activated carbon can not do accurately.  The smallest pore size created for carbon molecular sieve is 4A, but it exists in a 5A, and 10A (or 13X) as well.

Carbon molecular sieve specializes in separating oxygen from nitrogen, an important part in natural gas processing. This process is done with a PSA (Pressure Swing Adsorption) device in two phases.  The first phase sees the gas enter the PSA generator and the oxygen is adsorbed while the nitrogen passes through because the nitrogen molecules are too large and are used as a separate product.  The second phase sees the oxygen slowly released from the sieve at low pressures and thereby regenerating it so that the separation process can be repeated.

Carbon molecular sieve is used in this situation as opposed to activated carbon because the physical size between oxygen (0.28nm×0.40nm) and nitrogen (0.30nm×0.41nm) molecules are so close.  The pore sizes on carbon molecular sieve are able to accommodate these small size differences, where as activated carbon would just end up adsorbing both of them.

Molecular sieve isn’t used because it is a polar adsorbent, meaning its surface area attracts other polar molecules.  Oxygen is a non-polar molecule and would be attracted to other non polar surfaces.  Carbon molecular sieve is one of the few non-polar adsorbents out there which is why it is chosen over molecular sieve for this application.

In addition to separating nitrogen from oxygen carbon molecular sieve can be used for metal heat treatment, electron production, and as preservative in food products.

What’s the Difference Between Absorption and Adsorption…

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Posted on : 08-09-2011 | By : Mr. Green | In : Activated Alumina, Activated Carbon, Silica Gel, Zeolites
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…and Oxygen and Carbon Compound Adsorbents?

Absorption and adsorption are two natural occurring processes that are similar, but are not the same.  Here is a basic breakdown of how they are different:  absorption occurs when one material’s physical state is absorbed into another material’s physical state, while adsorption occurs when one material physically sticks to another material without changing it’s physical state.

Absorption occurs when a gas turns into a liquid, or a liquid into a solid, etc.  This is what separates it from adsorption, the physical state of the molecules have changed.  For example if you were to drink a glass of milk, your body would absorb it into your digestive system and eventually into your bloodstream.  The earth absorbs the suns rays and has converted its energy into the life sustaining planet we live on today.  The roots of plants absorb water when it rains converting into the energy it needs to survive.  All of these examples feature one material’s phase being turned into another.

Adsorption occurs when liquid or gas molecules stick to the side of surface, preserving their physical state.  This is useful for separating certain molecules from one another.  Adsorbents are most commonly found as carbon compounds or oxygen compounds.

Oxygen compound adsorbents are used to make products like silica gel which works to absorb moisture and reduce humidity levels or zeolites which can be tailored to specifically remove certain molecules from the air like carbon dioxide.

Carbon compound adsorbents like activated carbon can be effectively used to treat waste water and gas.  Contaminates will get stuck to the pores that are found all over the surface area of activated carbon while the water filters through.

Absorption and adsorption are both sorption processes, they both take in a substance or hold it in place and that is how they are related and why the are so similar, the process, however, is different.