Synthesis of thiol-functionalized magnetic graphene as adsorbent for Cd(II) removal from aqueous systems

• The adsorbent could be easily separated from solution under external magnetic field.
• The Langmuir adsorption maximum for Cd(II) ions reached 125 mg g−1.
• Adsorption mechanism was based on the synergistic effects of Fe3O4, SH and graphene.

Using FeCl3 and graphite oxide as precursors, we successfully synthesized magnetic graphene composite by one-step method and grafted thiol groups using (3-mercaptopropyl)trimethoxysilane (MPTES). Effects of initial solution pH, contact time and initial solution concentration of Cd(II) adsorption on as-synthesized thiol-functionalized magnetic graphene composite (M-Fe3O4-GO) were thoroughly explored. The maximum adsorption capacity of M-Fe3O4-GO for Cd(II) obtained from the Langmuir isotherm was 125 mg g−1. The M-Fe3O4-GO adsorbent showed excellent adsorption capacity for Cd(II), attributing to the synergistic effects of thiol groups, Fe3O4 nanoparticles and graphene nanosheets. The M-Fe3O4-GO adsorbent could be completely separated from the aqueous solution under external magnetic field and exhibited a potential application in heavy metal ions removal from aqueous solutions.

Figure optionsDownload as PowerPoint slide