Crushed, depitted peach stones were impregnated activated with 50% H3PO4 followed by pyrolysis at 500℃. Two activated carbons were produced, one under its own evolved gases during pyrolysis, and the second conducted with air flow throughout the carbonization stage. Physicochemical properties were investigated by several procedures; carbon yield, ash content, elemental chemical analysis, TG/DTG and FTIR spectra. Porosity characteristics were determined by the conventional N2 adsorption at 77 K, and data analyzed to get the major texture parameters of surface area and pore volume. Highly developed activated carbons were obtained, essentially microporous, with slight effect of air on the porous structure. Oxygen was observed to be markedly incorporated in the carbon matrix during the air treatment process. Cation exchange capacity towards Cu (II) and Cd (II) was tested in batch single ion experimental mode, which proved to be slow and a function of carbon dose, time and initial ion concentration. Copper was up taken more favorably than cadmium, under same conditions, and adsorption of both cations was remarkably enhanced as a consequence of the air treatment procedure. Sequestration of the metal ions was explained on basis of the combined effect of the oxygen functional groups and the phosphorous-containing compounds; both contributing to the total surface acidity character.

• Badie S. Girgis(Laboratory of Surface and Catalysis, Physical Chemistry Department, National Research Centre)
• Ahmed A. Elkady(Food Toxicology and Contaminants Department, National Research Centre)
• Amina A. Attia(Laboratory of Surface and Catalysis, Physical Chemistry Department, National Research Centre)
• Nady A. Fathy(Laboratory of Surface and Catalysis, Physical Chemistry Department, National Research Centre)
• M. A. Abdel Wahhab(Food Toxicology and Contaminants Department, National Research Centre)