Carbamazepine Degradation Mediated by Light in the Presence of Humic Substances-Coated Magnetite Nanoparticles

Abstract

The use of iron-based nanomaterials for environmental remediation processes has recently received considerable attention. Here, we employed core-shell magnetite-humic acids nanoparticles as a heterogeneous photosensitizer and iron source in photo-Fenton reaction for the degradation of the psychiatric drug carbamazepine (CBZ). CBZ showed low photodegradation rates in the presence of the magnetic nanoparticles, whereas the addition of hydrogen peroxide at pH = 3 to the system drastically increased the abatement of the contaminant. The measured Fe2+ and Fe3+ profiles point to the generation of Fe3+ at the surface of the nanoparticles, indicating a heterogeneous oxidation of the contaminant mediated by hydroxyl radicals. Products with a higher transformation degree were observed in the photo-Fenton procedure and support the attack of the HO• radical on the CBZ molecule. Promising results encourage the use of the nanoparticles as efficient iron sources with enhanced magnet-sensitive properties, suitable for applications in photo-Fenton treatments for the purification of wastewater.

Magnetic Nanoparticle–Polymer Composites Loaded with Hydrophobic Sensitizers for Photodegradation of Azoic Dyes

“…Photodegradation experiments of AB10B were carried out at room temperature in an RPR-100 Rayonet reactor (Bradford, CT, USA) equipped with eight RPR-3500 lamps. The spectral distribution of the lamps showed an emission centered at λ = 350 nm, and the incident photon rate measured using potassium ferrioxalate as the actinometer was 3.50 × 10 –5 einstein s –1 L –1 , as already reported. 50 mL of a 0.01 mM aqueous solution of the dye was irradiated at 350 nm, under mechanical stirring, in a cylindrical glass tube of 2 cm internal diameter ( V = 200 mL) in the presence of either MNC–PMAO–PN or MNC–PMAO, both at various concentrations (40, 100, and 200 mg L –1 ; expressed as iron oxide concentration).…”

The “Lab4treat” Outreach Experience: Preparation of Sustainable Magnetic Nanomaterials for Remediation of Model Wastewater

“…In the homogeneous phase, BBS (dissolved in water) have been proven to be efficient in the removal of naphtalensuphonates, azo-dyes and monochlorophenols, with good abatement results, as well as in terms of residual toxicity (the BBS themselves can be considered not toxic before and after irradiation) [ 60 ]. Heterogenized (supported) BBS, as the magnetic hybrids described above, have been also employed to photodegrade differently charged dyes [ 76 ], phenols [ 77 , 78 ], caffeine [ 37 , 61 ], carbamazepine [ 79 ], diclofenac [ 80 ] and other contaminants of emerging concern [ 81 ]. It is worth recalling that the heterogenization allows for the recovery and reuse of the active material, improving the sustainability of the whole process.…”

Microwave-Assisted Synthesis of Water-Dispersible Humate-Coated Magnetite Nanoparticles: Relation of Coating Process Parameters to the Properties of Nanoparticles

“…It is reasonable to assume that the key factor influencing the magnetic properties is the polyanion adsorbed on the nanoparticle surface. There are studies describing the magnetic properties of magnetite coated with humate, their results show that in comparison with unstabilized nanoparticles, samples with a stabilizer have a lower magnetization value in the range of 50-60 emu g −1 [64,65]. In these works, the weakening of magnetic properties is associated with a decrease in the mass fraction of the magnetic component in the composite.…”