Abstract:

Eupatoriumadenophorum stem was used to prepare activated carbon using phosphoric acid as activation agent with activation temperature at 550 ℃ and activation duration of 40 min. The influence of impregnation ratios of prepared activated carbon on the adsorption capacity was evaluated, the character and micro-structure were fully studied. Results showed impregnation ratios 2∶1 was optimal and characteristics of activated carbon with a high yield （40.2%） are: specific surface area （S_BET） 1 767.9 m²·g^-1, total volume 2.261 cm³·g^-1, iodine number of adsorbent （q_iodine） 1 056 mg·g^-1, amount of methylene blue adsorption of adsorbent （q_mb） 270 mg·g^-1, caramel A decolorization capacity 100% and ash 1.2%. The wide pore size distribution was described by BJH theory and SEM analysis. The activation course was discussed by TG analysis. It is demonstrated that Eupatorium adenophorum is an attractive source of raw material for producing high capacity activated carbon by phosphoric acid activation.

Key words: Eupatorium adenophorum, activated carbon, N₂ adsorption, porosity, TG analysis