1Chungnam National University 2Chungnam National University 3Chungnam National University 4Beijing University of Chemical Technology,
The oxygen and nitrogen enriched activated carbons were obtained from modification of commercial activated carbon by usingnitric acid, sodium hydroxide and urea. Zeta-potentials of modified activated carbons were investigated in relation to copper ionadsorption. The structural properties of modified activated carbons were not so much changed, but the zeta-potentials andthan other activated carbons in the entire pH region, and the pHIEP was shifted from pH 4.8 to 2.6, resulted in the largest copperion adsorption capacities compare with other activated carbons in the range of pH 3~6.5. In case of urea modified activatedcarbon, copper ion adsorption was larger than that of the as-received activated carbon from pH 2 to pH 6.5 even though the pHIEPwas shifted to pH 6.0, it was due to the coordination process operated between nitrogen functional groups and copper ion. Theadsorption capacity of copper ion was much influenced by zeta-potential and pHIEP of carbon adsorbent.