Fe3O4/TiO2-βCD magnetic particles: synthesis and application in solar photocatalysis for the degradation of orange dye II

• DOI: 10.22533/at.ed.317312301013

• Palavras-chave: -

• Keywords: Day; Paramagnetic properties; Photocatalytic evaluation; Solar radiation; Water pollution.

• Abstract:

  Water pollution is one of the most important problems in our days, the wastewater discharged by the textile industry exemplifies this problem because high concentrations of colorants and other organic compounds (additives, surfactants, etc.) have been reported from of this sector in aquatic ecosystems.

  The colorants in water bodies are slowly degraded, generating byproducts of greater toxicity that are easily bioaccumulative, consequently dissolved oxygen is reduced, and biogeochemical cycles are altered, affecting organisms at different trophic levels.

  The results obtained from the photocatalytic evaluation of Fe₃O₄ and the Fe₃O₄/TiO₂ and Fe₃O₄/TiO₂-βCD complexes indicated that Fe₃O₄ is the material that degrades in the highest percentage to the orange II azo dye, under a process of exposure to natural sunlight, in addition to showing adequate recoverability and reuse efficiency.

  Fe₃O₄ was synthesized by a simple precipitation technique, shows a particle size of 100.617 ± 42.043 nm, a surface charge of -12.133 ± 0.32 mV, a reflectance of 48.218 ± 0.258% at 900 nm wavelength and bandgap energy of 2.95 eV.

  The experiments related to the reuse of Fe₃O₄ for 5 cycles indicated that it maintained adequate efficiency, since the degradation percentages remained above 90% for up to three consecutive cycles. However, for the fourth and fifth cycles, the percentages of degradation obtained were lower, these being 86.925 ± 0.407% and 78.119 ± 1.770%, respectively.

  Thanks to its paramagnetic properties, the easy recovery through the use of a magnet and the degradation percentages obtained, the synthesized Fe₃O₄ proves to be an alternative for the environmental restoration of contaminated water, this textile dye in areas with optimal solar radiation conditions.