Removal of Toxic Metal-Ion Pollutants from Water by Using Chemically Modified Carbon Powders

The thermodynamics of and the kinetic parameters controlling the sequestration of the toxic heavy‐metal ion CdII from aqueous media by using a novel material consisting of glassy carbon microspheres (10–20 μm in diameter) chemically modified with L‐cysteine methyl ester are presented. In an effort to reduce the cost and increase the efficiency of toxic‐metal‐ion removal, this modification strategy was expanded to attach L‐cysteine methyl chemically ester to less‐expensive graphite powders (2–20 μm in diameter), and the thermodynamic and kinetic parameters of the sequestration of CdII, CuII, and AsIII toxic metal ions are presented. It was found that the use of chemically modified graphite powder greatly increased both the rate and the amount of metal ions removed from aqueous media. This work has important potential applications to filtration of drinking water and environmental remediation. “Out, damned spot!” Modified carbon powders were developed and optimized to adsorb irreversibly large quantities of toxic heavy metals such as CuII, CdII, and in particular AsIII from aqueous media rapidly and effectively. These materials have the potential to be used in both environmental remediation and filtration of drinking water, particularly in developing countries. (l.o.d.=Limits of detection.)