Activated carbon is considered as crude form of graphite. But unlike graphite structure it has random imperfect structure with macro and micro pores. The graphite structure gives the Activated Carbon it's very large surface area. 3 gram of Activated Carbon can have a surface area of a football field. Activated Carbon has the strongest physical adsorption forces. The surface area of Activated Carbon varies from 500 m2/g to 2000 m2/g
Activated Carbon can be manufactured from many materials containing high carbon content such as coconut shell, wood, coal, bituminous, coir, lignite, peat, petroleum pitch etc. Carbonaceous materials can be activated using two methods, steam activation and chemical activation.
- Steam Activation
In this process the material is activated with steam at very high temperature. The chemical reaction between the carbon and the steam take place at the internal surface of the carbon. Steam activation enlarges the pore structure and thus increases the internal surface area. It is the most widely used process to activate carbonaceous materials. It is considered as the best pollution free method of activation.
- Chemical Activation
This type of activation is only useful for the carbonization of wood, sawdust or peat. In chemical activation the raw material is mixed with an activating agent such as phosphoric acid that swells the material and open up the cellulose structure. It is then carbonized and dried in a rotary kiln at low temperature. It dehydrates the raw material resulting in the amortization of the carbon, thereby creating high porous structure.
At Clean Carbon we follow steam activation method since it is the most environmental friendly method of activation process.
The effectiveness of Activated Carbon is depends on its internal surface area. Effectiveness is increased with increase of internal surface area. The usual surface area of Activated Carbon varies from 500 m2/g to 1750 m2/g or even more
Coconut shell based Activated Carbon is considered as the best Activated Carbon ever made.Coconut shell based Activated Carbon is extremely porous with large surface area Porous Structure suitable for fast adsorption Naturally occurring raw material Zero carbon footprint Very High Hardness Very low impurity content
Adsorption is the process where the molecules of the substance attract on the surface of the activated carbon. Activated Carbon is characterized with high micro and macro porosity, which enables the carbon to adsorb the adsorbates into its internal surface. There are two types of adsorption.
- Physical adsorption
Physical adsorption is happening when the substances to be adsorbed are held on the internal surface of Activated Carbon due to Vander Waals force of attraction between the molecules. The force of attraction diminishes with increase in distance between pore wall and the substance molecules.
Strong forces of attraction between the molecules of the adsorbate and the chemical complexes that impregnated on the pore walls of Activated Carbon
- Granular Activated
Carbon is irregular in shape which is formed by sieving and milling of Activated Carbon. Granular Activated Carbon is used for purifying large volume of gas or liquid substances. Granular Activated Carbon is harder and lasts longer than Powdered Activated Carbon. It can be reactivated and reused several times.
- Powdered Activated
Carbon is usually used for liquid phase applications and flue gas applications. Powder Activated Carbon has a particle size distribution ranging from 5 to 150 micrometer. It is used in batch and continuous process. Powder Activated Carbon cannot be reactivated and reused as GAC.
- Surface area
Surface area of Activated Carbon varies from 500 m2/g to somewhat 2000 m2/g. That means just 3 gram of Activated Carbon can have the surface area of a football field. The surface area of carbonaceous materials can be increased by activation process.
- Total Pore Volume (TPV)
TPV refers to the total space of the pores in an Activated Carbon. The effectiveness of Activated Carbon is increased with increase of total pore volume. It is expressed in milliliters per gram (ml/g)
- Pore volume distribution
The significance of Activated Carbon is its unique distribution of pore sizes. For decolorisation applications high distribution of mesopore is required.
- Resistance to abrasion.
- Adsorption capacity.
- Particle size distribution for optimal flow.
- Rate of adsorption and desorption.
- Consistency of product in applications.
- Presence of other substances that may affect or interfere with loading of carbon.