Activated charcoal is used for the purpose of removing hydrocarbon impurities from the carrier as well as fuel gases, especially for reducing the errors in analysis while using FID. These materials have a very large surface area & pore diameter to adsorb large size hydrocarbon molecules. 

Activated Charcoal / Carbon material should be replaced after 1 ½ to 2 years. Keep the activated Charcoal / Carbon at 110° C for 2 – 3 hrs for regeneration or its better to replace the Activated Charcoal / Carbon