The efficient sorbents for the heavy metal ions elimination from wastewater, like graphene and carbon nanotubes, are widely utilized in nanomaterials development. Clays (bentonite), activated carbon, metal oxides, and zeolites are commonly used as adsorbents in the heavy metals removal from solutions, such as Pb (II), Zn (II), Cd (II), Ni (II), as well as Cu (II). The graphene oxide (GO), in this study, was produced from graphite powder using a modified Hummer's technique, then altered by doping with acid-activated bentonite. SEM, EDX, TEM, FTIR, and XRD characterized modified graphene oxide. The Cu(II) and Zinc (II) were adsorbed onto the modified GO using the simple batch-adsorption mode. PH values, initial concentration, adsorbent dosage, reaction temperature, and contact time were used to successfully vary the percentage of removed Zn(II) and Cu(II).

At pH 5.6 under the ambient conditions ( according to the diagram of zero point charge ), over 45 min adsorption time, and 0.5 g/L adsorbent dose, the highest removal efficiency of Cu(II) and Zn(II) were 99.75% and 99.79%.

The highest adsorption capacities of modified GO were 39.896 and 39.954 (mg/g) for Cu(II) and Zn(II), respectively, and the experimental values correlate well with the Langmuir isotherm.