The electrochemical properties of electric double layer capacitor(EDLC) was studied by controlling pore size distribution and specific surface area of the activated carbon fiber(ACF). The mesoporous ACF, which was prepared by the iron exchange method, showed the tendency of increasing average pore size and decreasing total surface area. The mesoporous ACF (surface area = 2225 m2/g, pore size=1.93 nm) showed increased mesopore(pore size=1~3nm) volume from 0.055 cc/g to 0.408 cc/g compared to its raw ACF. The charging capacity of the EDLC which uses the prepared mesoporous ACF also increased from 0.39 F/cm2 to 0.55 F/cm2. From these results, it can be known that the electrochemical properties of EDLC are mainly dependent on the specific surface area, but above the surface area 2200 m2/g, it is the mesopore volume that affects the performance of the capacitor considerably. Because the increased mesopore volume results in a decreased ion mobility resistance, the charge capacitance is enhanced.

Activated carbon fibers were prepared from the petroleum isotropic pitch and organometallic compounds. The metals were dispersed uniformly in the ACFs. The specific surface area and pore size distributions of metal containing ACFs were measured. The mesopores of ACFs were developed by Co, Ni, and Mn metals addition, and the catalytic reactivity of ACFs' SOx removal was increased by adding Ni and Pd metals. It was found that the mesopores did not work forthe improvement of catalytic reactivity of ACFs' SOx removal with the blank experiment using the metal removed ACFs.