Removal of naproxen and diclofenac using magnetic nanoparticles/nanocomposites

Magnetic iron oxide and iron/copper nanoparticles were synthesized using Lathyrus brachypterus extract, and then magnetic Fe3O4-CS, Fe3O4-AT, Fe/Cu-CS and Fe/Cu-AT nanocomposite beads were synthesized using chitosan and alginate natural polymers. They were used for both adsorption and heterogeneous catalysts for the catalytic wet peroxidation (CWPO) of naproxen (NPX), diclofenac (DCF) and NPX + DCF drugs which are important micro-organic pollutants, separately and together (NPX + DCF) from aqueous media. In adsorption studies, the drugs were adsorbed very quickly in the first minutes and then, desorbed in between 8 and 10 min. In competitive adsorption, the adsorbents showed selective properties for DCF and NPX. In CWPO technique, drug removal was achieved in 9 min with a conversion capacity of 92% for DCF with Fe/Cu-CS and 84% for NPX with Fe/Cu-AT optimum experimental conditions, such as pH 5, 30% of H2O2, 100 mg catalyst and 298 K. Based on reusability of the catalysts, it was seen that there was a slight decrease in the removal efficiencies in the third cycle and the stable and active structure of the catalyst was preserved to the desired extent. Furthermore, the oxidation reaction was in good agreement with the pseudo-first-order kinetic model.

Automated summary

Magnetic nanocomposite materials synthesized from natural polymers show fast adsorption and removal of drug pollutants in water. The catalytic process achieves high efficiency under optimal experimental conditions.