Carbon materials are activated through a series of processes which includes:
• Removal of all water (dehydration)
• Conversion of the organic matter to elemental carbon, driving off the noncarbon portion (carbonization)
• Burning off tars and pore enlargement (activation).
Initially, the material to be converted is heated to 170° C to effect water removal Temperatures are than raised above 170° C driving off CO* CO, and acetic acid vapors. At temperatures of about 275" C, the decomposition of the material results and tar, methanol, and other by-products are formed. Nearly 80 percent elemental carbon is then effected by prolonged exposure to 400- 600° C. Activation of this product follows with the use of steam or carbon dioxide as an activating agent. The superheated steam, 750-950" C, passes through the carbon burning out by-product blockages, and expanding and extending the pore network.
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