Application of Novel Fulvic Acid-Coated Magnetite Nanoparticles for CO2−-Mediated Photoreduction of Cr(VI)

• Published in: Water, air, and soil pollution air, and soil pollution, 2018-02, Vol.229 (2), p.1-9, Article 39
• Main Authors: Arce, Valeria B., Mucci, Carla R., Fernández Solarte, Alejandra M., Torres Sánchez, Rosa M., Mártire, Daniel O.
• Format: Article
• Language: English
• Subjects: Acids; Aerobic conditions; Anions; Anoxia; Anoxic conditions; Atmospheric Protection/Air Quality Control/Air Pollution; Carbon dioxide; Chromium; Climate Change/Climate Change Impacts; Composting; Earth and Environmental Science; Environment; Environmental monitoring; Formic acid; Fulvic acids; Hydrogeology; Irradiation; Magnetite; Nanomaterials; Nanoparticles; Oxic conditions; Photochemistry; Photodegradation; Photoreduction; Reduction; Soil Science & Conservation; Ultraviolet radiation; Vermicomposting; Water Quality/Water Pollution; Worms
• ISSN: 0049-6979; 1573-2932
• DOI: 10.1007/s11270-018-3693-5

We here isolate fulvic acids from vermicompost to prepare and characterize novel fulvic acid-coated magnetite nanoparticles. UV-A irradiation of suspensions of the nanoparticles under different experimental conditions led to photo-reduction of Cr(VI). In anoxic conditions in the presence of formic acid, after 60 min of irradiation ca. 100% of Cr(VI) was reduced. Under these conditions, the carbon dioxide radical anions, CO 2 .- , mediated the photo-reduction of Cr(VI). However, the high reduction potential of Cr(VI) and the variety of reactive species generated upon UV-A irradiation make this nanomaterial also suitable for Cr(VI) photo-reduction also under aerobic conditions in the presence of formic acid or under anoxic conditions without the addition of formic acid. The possible photodegradation routes involved are discussed in detail.