Preparation and characterization of activated carbon from coal by chemical activation with KOH

Abstract

In this study, activated carbons (ACs) were produced from coal using potassium hydroxide as a chemical-activating agent. The preparation procedure composed of KOH impregnation followed by activation at 700°C–900°C under the nitrogen atmosphere for the time duration of 1 h. The effects of various activation temperatures and various KOH to coal ratios on the porous structure of the products were examined. The resulted ACs were also characterized by various techniques such as Brunauer-Emmett-Teller (BET) analysis, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and X-ray diffraction (XRD) to confirm their characteristic properties. The surface area and pore volume of the resulted ACs increased with increasing temperature. The activated sample obtained from KOH to coal ratio of 2:1 and at heat treatment of 900°C under N2 environment for 1 h found in the maximum BET specific surface area of about 1598.4 m2/g.