Preparation and characterization of activated carbon from cotton stalks in a two-stage process

摘要

Activated carbons are prepared from cotton stalks by chemical activation with ZnCI_2, H_2SO_4 and physical activation using CO_2 and steam-CO_2 mixture for temperatures of 750, 850 and 900℃. The effects of activation temperature and duration time, impregnation concentration of agent, impregnation times, and physical activating agent are examined. These materials are characterized by adsorption/desorption of N_2 to determine the BET areas, thermogravimetric analysis (TG, DTA), FT1R and scanning electron microscopy (SEM). ZnCl_2 under CO_2 atmosphere was found more effective than H_2SO_4 as a chemical reagent under identical conditions in terms of porosity development. The maximum BET surface area is found to be 2053 m~2/g for active carbons produced with ZnCl_2 activation under CO_2 atmosphere.