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In recent decades, the rapid development of science & technology and industry makes human life more colorful. With results of this, however, the caused pollution impacts on the earth that human being live on should not be ignored. In the process of protecting the environment, depending on its unique efficiency and reliability on removing contaminants from liquid and gas phrases, activated carbon has been already more and more focused on by social and public. With amazing adsorption ability, activated carbon is able to adsorb organic and inorganic substances in most of the liquid and gas, and is widely used in food, medicine, chemical industry and water treatment etc.

1. What is activated carbon? What is activated carbon made from?

The primary raw material for activated carbon is any organic material containing rich carbon content, such as sawdust , wood, coal, petroleum coke, coconut shells, fruit nut shells, and bamboo etc. Through various activation processes, these carbonaceous materials are converted to activated carbon by heat treatment at a controlled atmosphere and high temperature. During the activation process, a large surface area and a complicate pore structure are created where the adsorption takes place.

2.How is activated carbon produced?

Utilizing various materials, Activated carbon is manufactured by physical activation and chemical activation at high temperature.
The activation method that carbonaceous materials mixed with some chemicals are treated under thermal environmental is called chemical activation. The activated carbon made by chemical activation is often called chemically activated carbon.
The activation method that carbonaceous materials are treated at high temperature (600~1000℃) by thermal stream such as heated steam, carbon dioxide, air (mostly oxygen ) or the mixtures of these gases (called as flue gas) is called physical activation.
It should be pointed out that composite activation technology by combining chemical and physical activation has comes out now. This technology has better performance in control of the pores structure of activated carbon and can create unique products with special functions.

3.How large is the surface area of activated carbon?

One gram of activated carbon has a surface area in excess of 500 m² , almost a football filed.

4.What is the adsorption principle of activated carbon?

There are two kinds of adsorption principles for activated carbon.
   Physical adsorption takes place in the course of removing contaminants from liquid and gas stream. The porous structure provides activated carbon with a large surface area, which makes activated carbon adsorb contaminants very easily. Like magnetic force, attractive force is also existed among all molecules. As a result, the mass of molecules gathered at pore walls of activated carbon can create powerful attractive forces which can draw the molecules of contaminants through to the pore channels of activated carbon. It should be pointed out that the molecules of contaminants to be adsorbed must be smaller than the size of pore opening so that they can pass into the carbon pores and accumulate. This is why we are always using different raw materials and conditions of activation to produce varieties of activated carbon with different pores structure so as to make our products suitable for different applications.
       Apart from physical adsorption, chemical reactions can occur on a carbon surface. Activated carbon not only contains carbon content but also has a little hydrogen content and oxygen content on its surface, which exists in the form of chemical combinations and function masses, including Carbonyls, Hydroxyls, Phenols, Esters, Quinones and Ethers, etc. These oxidizing agents and complexes on the carbon surface can take chemical reactions with the matters that are adsorbed by carbon. The following is a typical example: during the water treatment process, activated carbon can take reactions with chlorine in water and convert the chlorine to chloride. What's more, the chlorine is removed and there are no objectionable tastes and odors in water any more.

5.How to select activated carbon

Different raw materials and different activation methods inevitably result in different properties of activated carbon. In general, you must make sure the activated carbon you want is powder form or granular form. Mostly, powder activated carbon is used in liquid phase adsorption, and granular activated carbon can be used in both liquid and gas phase adsorption. The pores structure, size of particle and functional group on the surface are very important to the adsorption of activated carbon. You have to find the right activated carbon as per your filtration equipment, filtration speed and the size of molecules to be adsorbed. If you want us to help you select the activated carbon, please all our service telephone: +86 21 59118189.

6.What is activated carbon reactivation?

Reactivated carbon is formed by adding thermals like heated steam and carbon dioxide into a reactivation furnace to exert a heat treatment on used activated carbon. After this treatment, used activated carbon will get chemical constituents removed and regain adsorption ability and can be reused by customers.

7.How long does activated carbon work?

In general, powder activated carbon can be used for one time only and cannot be used repeatedly. The key is to determine the dosing quantity
For granular activated carbon, as it does not change color or shape when it adsorbs contaminants. Therefore, The best way to tell if the carbon is needed to change is to test the outlet of the carbon column for the contaminant being removed. Once the concentration of the contaminant is above the acceptable emission or discharge limits, the activated carbon is considered spent and has to be changed with fresh activated carbon.

8.How to deal with the spent activated carbon?

The spent activated carbon is often treated as industrial garbage. In order to save resources and protect our environmental, we suggest you can contact with us and send the spent activated carbon back to our plant for reactivation treatment. Certainly, not all of spent activated carbon can be reactivated in our plant. Please make confirmation with our engineer for workable possibility before you intend to reactivate your spent activated carbon in our plant.

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