Preparation and Characterization of Activated Carbon from Poplar Sawdust by Chemical Activation: Comparison of Different Activating Agents and Carbonization Temperature

Abstract

Activated carbons were prepared from poplar sawdust by chemical activation using ZnCl2, H3PO4 or KOH. The influence of activating agents, carbonization temperatures ranging from 500 ºC to 800 ºC, and mass ratio of chemical agent to precursor (1:1 and 2:1) on the porosity of activated carbons were studied. The properties of the carbons were characterized by adsorption/desorption of nitrogen to determine the BET areas, scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR). It was determined that the surface morphology and textural characteristics of activated carbons vary depending on the carbonization temperature or chemical agent. Maximum surface areas were obtained at carbonization temperatures of 500, 700 and 800 ºC for H3PO4, KOH and ZnCl2 activation, respectively. The activated carbons prepared using ZnCl2 and H3PO4 activation had a higher BET surface area (nearly 1100 m2/g) than that of the KOH activation (761 m2/g). This study also presents a comparison of mechanisms of activating agents and carbonization temperature. As a result of the experimental studies, positive results were obtained, and the production of activated carbon with a high surface area was conducted.