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The presence of heavy metals such as cadmium(II), chromium(III), zinc(II), and copper(II), etc. in water and wastewater has been of great public concern. Heavy metals are frequently discharged into the environment from a number of industrial processes, including extractive metallurgy processes, electroplating, refining, leather tanning, metal finishing, printed circuit board manufacturing, and dyeing. Heavy metals are not biodegradable and tend to build up in living organisms, causing several diseases and disorder. It has been shown that copper deposited in human skin, liver, pancreas, brain, and myocardium may result in Wilson's disease. The maximum contaminant level goal under the Lead and Copper Rule, promulgated by the U.S. EPA in 1991 to limit the concentration of lead and copper in public drinking water at the consumer's tap, is 1.3 mg/L of copper. A wide range of methods have been used to remove heavy metals from aqueous solutions, such as electro- chemical precipitation, ultra-filtration, ion exchange, reverse osmosis, and sorption onto solid substrates such as activated carbon. Each of these methods has some significant drawbacks in practice. A major disadvantage of precipitation is the production of sludge. Ion exchange is considered a better alternative than precipitation. But, it is not economically feasible due to high operational cost. Adsorption using commercial activated carbon (CAC) can remove heavy metals from wastewater, such as Cd, Ni, Cr, Zn, and Cu. However, CAC is an expensive material for heavy metal removal. As a result, researchers have focused on finding low-cost adsorbents and investigated several absorbents such as bagasse sugar, starch xanthate, sawdust of pinus sylvestris, chitosan, bentonite, and discarded automobile tires. Discarded tires are an interesting and inexpensive medium for the sorption of toxic metals from aqueous solutions. In this study, crumb rubber was chosen for the removal of copper from aqueous solution and used for the pre-concentration/separation of copper prior to its determination by flame atomic absorption spectrometry (FAAS). At first the adsorption properties of crumb rubber were investigated by batch technique using inductively coupled plasma-optical emission spectrometry (ICP-OES). The effects of pH, contact time and initial metal concentration on the removal of Cu(II) were studied. Experiments with solution pH as a variable were conducted to determine the optimum pH range for maximum Cu adsorption by crumb rubber at different initial Cu(II) ion concentrations. In all cases, it was found that the uptake increased as the initial pH increased from 1.5 to 6 and slightly changed at the pH value of 7. Therefore, the following experiments were performed in the solution pH of 6. The effect of contact time on the removal of copper by crumb rubber at different initial Cu(II) ion concentrations was studied. In all cases, the removal increases with time and attains equilibrium in 72 hr. The metal uptakes versus time curves are single, smooth and continuously leading to saturation, suggesting the possible monolayer coverage of metal ions on the surface of the adsorbent. The removal of Cu(II) by adsorption on crumb rubber has been shown to take place rapidly for all initial concentrations.… [ABSTRACT FROM AUTHOR]