1. What is activated charcoal?
The simple answer: it is the charcoal made from different sources such as wood, coconut shell, bamboo, or coal, that is then “activated”, with steam or acid. This process carves away the internal structure of the charcoal particles producing a much higher [internal] surface area. This “activated charcoal” is then used in thousands of applications primarily to adsorb unwanted chemicals so that they can be neutralized or removed completely from the product that is being “cleaned”.
For a more detailed answer, CLICK “What is Activated Charcoal?”
2. What is the difference between hardwood, coconut, bamboo, or coal?
Disregarding costs, each raw material has its own unique characteristics that make them more suitable for some applications than others. When activated, the various grades of charcoal produce unique internal pore structures that accommodate different sized molecules. For example coconut activated charcoal works very well for air and vapor applications that target odor control, while coal-based activated charcoal works well for color removal.
For specific applications CLICK Applications
3. What is the difference between “activated charcoal” and “activated carbon”?
There is no difference. Activated charcoal tends to be the lay term. “Activated carbon” is more commonly used in the manufacturing/technical sectors. Other terms are activated coal. Sometimes “active” is substituted for “activated”.
4. How long will activated charcoal last?
If stored in airtight containers, activated charcoal has an almost indefinite shelf life.
5. Does it expire?
If left exposed to the environment, in time, activated charcoal will adsorb various pollutants and eventually “fill up.” Otherwise, if stored securely, there is no expiration limit other than what certain arbitrary governmental regulations may require as a maximum.
6. Is it Food Grade?
Activated Charcoal is considered GRAS – “Generally Recognized As Safe”. More than this, some manufacturers may go a step farther and have their product certified under several different agencies such as NSF, USP, UL, ASTM, ANSI, AWWA…
7. What is the difference between Virgin or reactivated or regenerated charcoal?
• Virgin activated charcoal is the original product that has never been used. All the activated charcoal sold by BuyActivatedCharcoal.com is virgin activated carbon.
• Reactivated charcoal is activated charcoal that has finished its lifespan in a particular application and is then exposed again to the steam-activation process that removes the adsorbed pollutants and restores about 90% of the activity level, so that it can be safely used again. For example, at the municipal level (water treatment facilities) where large volumes of activated carbon are employed and the spent carbon in the majority, if not all, cases is considered non-hazardous, there is a great opportunity to reactivate the carbon and reuse it. The reactivation process burns up about 10% of the original product producing about 20% of the greenhouse gases compared to new carbon production. There is also the benefit of less landfill.
• Regenerated carbon usually refers to a process where the spent carbon is washed with either water or a chemical agent to remove a portion of the contaminants adsorbed by the carbon. For regeneration, the GAC is treated in the adsorption vessel. Only about 5 - 50% of the original activity of the activated carbon is restored.
8. Can you grind Granular Activated Charcoal (GAC) into Powder (PAC)?
Yes, you can. But unless you take the extra time, and effort it will not be as fine a powder as is commercially made. You will also quickly find it is a vey messy process.
9. What are the different applications?
Activated charcoal is primarily used to remove some contaminant from an end product, or to refine, purify or otherwise concentrate the desired end product. It could be the removal of CO2 from the air in a nuclear submarine, or pollutants in the recycled water on the international space station or your home aquarium, or different odors, colors, flavors or toxins from pharmaceutical drugs ornutraceuticals. It could be the removal of H2S from fuel cells in the new hybrid cars, or cyanide in gold extraction. So diverse is activated charcoal in its applications, one manufacture asserts, "A thousand applications today, a thousand and one tomorrow". Activated charcoal is able to capture far infrared rays and microwave, it is used in the most sophisticated sound systems to clean out "dirty" sound, it is woven into Activated Carbon Cloth and pleated in NBC suits.
10. How is an activated charcoal selected for a particular application?
• Applications are divided broadly into two groups: air/vapor filter and water/fluid filter applications. Air and vapor filters tend to use the larger sizes of GAC, while water and fluid applications use smaller GAC or even powdered activated charcoal (PAC).
• The flow rate of the medium through the charcoal filter will determine the size of the charcoal particle. Sufficient contact time with the charcoal is paramount. The smaller the charcoal particles in the filter bed the faster they will work, but the smaller particles will also restrict the flow rate. The perfect formula will match the particle size to the desire flow rate.
• The molecular size of the target contaminant is the next deciding factor. There are three basic activated carbon pore structures: micro (smallest – less than 20 Å) meso (intermediary - 20 Å - 50 Å) and macro (largest - greater than 50 Å)
• The target contaminant is matched to an activated carbon with a particular pore size.
• Activated charcoal produced from coconut shell is known for its micro pore structure which works well for small air/gas molecules. Wood-based charcoal has a more mid-range pore structure and coal-based has larger macro-pores that accommodate the larger color and protein molecules.