Activated Carbon by Gas Activation

Activation with steam and carbon dioxide proceeds at 800 to 1000°C. 

In the gas activation of uncarbonized feedstocks, a low temperature carbonization process, leading to carbonization, has to be carried out before activation. This low temperature carbonization process has a considerable influence on the pore distribution in the final product. 

which contains a high fraction of volatile components, has to be preoxidized and then carbonized at low temperatures, whereas anthracite can in principle be activated directly. In practice, however, pulverization, briquetting with the aid of a binder, briquette communition and low temperature carbonization are generally carried out. This makes subsequent activation much easier. Lignite low temperature coke can be directly activated. 

If formed carbon is manufactured from low temperature lignite coke, a low temperature carbonization of the binder (pitch, organic resin), which consolidates the ground coke, has to be carried out. In this way the binder is also carbonized (see Section 5.7-3). 

The ash content of materials such as coal or lignite can, for example, be reduced by acid treatment (with hydrochloric acid, nitric acid) either before or after activation. 

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