Activated carbon is often used in metal ion adsorption processes due to the large surface area it provides. In addition, activated carbon is an inexpensive and environmentally friendly material that provides good cost-benefit for the industries that use it. In this study, activated carbons from different sources were characterized physically and chemically. For example, surface area, thermogravimetric analysis, scanning electronic microscopy, energy dispersive X-ray fluorescence, zeta potential, surface basic and acid groups, iodine number, and ash content were determined. Principal components analysis (PCA) was also used to evaluate the relationship between these characteristics and the origin of the activated carbons examined. The capacity for these adsorbents to simultaneously remove Cu(II), Cr(VI), and Zn(II) from a metallurgic effluent were also evaluated, with some of the adsorbents being able to remove these ions very efficiently. (C) 2013 Elsevier B.V. All rights reserved.