In
this work, we report a room-temperature approach to synthesizing
nitrogen-functionalized graphene oxide (GO). The chemical structure
of GO- triethylenetetramine-methacrylate (GO-TETA-MA) was characterized
by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy,
and <sup>13</sup>C nuclear magnetic resonance, respectively. The GO-TETA-MA
demonstrated extremely efficient removal of copper from wastewater.
The adsorption capacity was found to be 34.4 mg/g for Cu(II) (at pH
= 5 and 25 °C). The final concentration of Cu(II) was lower than
the quality standard for groundwater and even lower than the allowable
level of copper contaminant in drinking water in China. The effects
of several parameters on adsorption, including pH value, contact time,
adsorption temperature, initial concentration, acid stability, and
thermal stability, were investigated. Kinetic data were well-described
by a pseudo-first-order model. Both Freundlich and Langmuir isotherm
models were applied to the experimental data analysis, and the former
proved to be a better fit. The underlying mechanism of synergistic
adsorption of heavy metal ions was considered. Then, the removal efficiency
for four copper fungicides was studied and was found to reach 100%.
These results suggest that GO-TETA-MA has the potential to be applied
in environmental management
