The BET surface areas, total pore volumes and average pore diameters of the activated carbons prepared from the grape stalk are shown inTable 3. The results show that the using ZnCl2as an activating agent is very efficient to produce activated carbons with high surface area and porosity and that the impregnation ratio has a significant influence on pore development. Surface area and porous structure of the activated carbons were increased by using ZnCl2along with carbonization. As the impregnation ratio was increased from 0.5 to 2, the surface area of activated carbons prepared increased from 482 to 1411 m2/g, which is a relatively high surface area for an activated carbon. The micropore volume and the total pore volume followed the same trend. The dramatic increases in the pore volumes and average pore diameters at higher impregnation ratios were observed due to deformation of macropores and transformation into mesopores with the ZnCl2effect.