A novel activated carbon was prepared from spent lubricating oil by chemical activation. Preparation of this material involved the oxidation of lubricating oil with a mixture of sulfuric and nitric acid solutions. FT-IR analysis showed the presence of carboxylic, phenolic and lactonic groups on the surface of this material. Equilibrium sorption isotherms prepared for this carbon demonstrate that it has a significantly high capacity for lead and cadmium sorption. A maximum of 250 mg Pb
and 150 mg Cd
were adsorbed per gram of this carbon.