Nuclear chemistry

Adsorption

Composite number

Engineering

Oxide

Nanoparticle

Materials science

Iron oxide

Carbon fibers

Inorganic chemistry

Chemical engineering

Activated carbon

Nanotechnology

Organic chemistry

Aqueous solution

Composite material

Chemistry

Water Resources and Industry

Iron oxide (Fe3O4) and iron oxide/activated carbon (Fe3O4/AC) were fabricated by co-precipitation method for the removal of Cr(VI), Cu(II) and Cd(II) ions from aqueous solution in batch mode. These nanoparticles were characterized by BET, FTIR, XRD, SEM/TEM and VSM. The optimum conditions for the removal of ions were pH = 2 for Cr(VI) and 6 for Cu(II) and Cd(II), initial metal ion concentration = 50 mg L−1, nanoparticle dose = 50 mg/10 mL, temperature = 25 ± 1 °C, shaking speed = 180 rpm and contact time = 3 h. The equilibrium data of ions sorption were well described by Langmuir, Freundlich, Redlich-Peterson and Intraparticle Diffusion model. The R2 values obtained by Langmuir model were highest by Fe3O4/AC for Cr(VI) = 0.9994,Cu(II) = 0.9998 and Cd(II)= 0.9750. The temperature dependent study in the range of 288–328 K confirmed that the adsorption process was endothermic in nature. Desorption studies with 0.1 M HCl stated that these nanoparticles can be regenerated effectively and can be used after four adsorption-desorption cycles without any mass loss.

Development of iron oxide/activated carbon nanoparticle composite for the removal of Cr(VI), Cu(II) and Cd(II) ions from aqueous solution