Preparation of activated carbons from poplar wood by chemical activation with KOH

Abstract

Low-cost activated carbons were prepared from poplar wood by chemical activation with KOH as a chemical activating agent. The thermal behavior of KOH-impregnated poplar wood was analyzed in detail via the Thermogravimetric analysis (TG, DTG and DSC). Moreover, the effects of impregnation ratio, activation temperature and activation time on the porous structure were investigated. Results showed that KOH has catalytic effect which could promote the pyrolysis of poplar wood at lower activation temperature. The activated carbons from poplar wood with KOH activation could be formed at 550–700 °C. The specific surface area and pore volume of activated carbon increased with increasing the impregnation ratio, activation temperature and activation time. Moreover, influence of increasing impregnation ratio on the porosity of activated carbon is sensitive to activation time. The maximum specific surface area (1551 m2/g) activated carbon with uniform micropores distribution was obtained at activation temperature of 700 °C, impregnation ratio of 3/1 and activation time of 30 min. Carbon skeleton could break seriously when activation temperature is higher than 750 °C.