Adsorption of Cd(II) by petroleum coke treated with KOH activation and oxidation

Abstract

Activated carbon (AC) was prepared from petroleum coke (PC) by KOH activation and characterized with N₂ adsorption-desorption isotherms and elemental analysis. Pore development was promoted by increasing the KOH/PC mass ratio, and a high surface area of more than 3000 m²/g was obtained using KOH/PC with a mass ratio of 4 or more. Similar pore properties were obtained for a low sulfur-containing petroleum coke (LSPC). Although the sulfur content of PC was decreased by KOH activation, the reduction of sulfur had little effect on the pore development. The prepared ACs were further oxidized by an ammonium persulfate solution and used for a Cd(II) adsorption experiment. A large amount of Cd(II), about 1.7 mmol/g, was adsorbed by oxidized AC prepared from KOH-activated PC with a surface area of 1700 m²/g.