High surface area microporous activated carbon has been prepared from Fox nutshell (Euryale ferox) by chemical activation with ZnCl2 as an activator. The process has been conducted at different impregnation (ZnCl2/Fox nutshell) ratios (1-2.5) and carbonization temperatures (500-700 degrees C). The thermal decomposition behavior of Fox nutshell and impregnated Fox nutshell has been carried out by thermogravimetric analysis. The pore properties including the BET surface area, micropore surface area, micropore volume, and pore size distribution of the activated carbons have been determined by nitrogen adsorption-desorption isotherms at -196 degrees C using the BET, t-plot method, DR, and BJH methods. The BET surface area, the microporous surface area, total pore volume, and micropore volume have been obtained as 2869 m(2)/g, 2124 m(2)/g, 1.96 cm(3)/g, and 1.68 cm(3)/g, respectively, and the microporosity percentage of the prepared activated carbon is 85.71%. The prepared activated carbons have been also characterized with instrumental methods such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM). (C) 2015 Elsevier B.V. All rights reserved.