Performance comparison of commercial TiO2: separation and reuse for bacterial photo-inactivation and emerging pollutants photo-degradation

Moles, Samuel (Universidad de Zaragoza) ; Valero, Pilar ; Escuadra, Silvia ; Mosteo, Rosa (Universidad de Zaragoza) ; Gómez, Jairo ; Ormad, María P. (Universidad de Zaragoza)

Resumen: This research aims to compare the disinfection and degradation effectiveness in water of a commercial suspension of nano-TiO2 (TiO2Levenger) with the standard TiO2Degussa P25. Photo-inactivation and photo-degradation experiments were conducted with UVA-vis light. Concerning the disinfection, the effects of TiO2 dose (0–2 g/l), water matrix, bacterium type (Gram-positive or Gram-negative), and bacterial regrowth after the photo-treatments were studied for each catalyst. The experimental results show that Enterococcus sp. (Gram-positive) was more resistant to the photo-treatments than Escherichia coli (Gram-negative) for both catalyst; however, postirradiation trends showed similar behavior for both bacteria, favoring regrowth for short-treated cells and decay for longer-treated ones. Caffeine was selected as a model substance of pharmaceuticals and personal care products. In terms of caffeine removal, the effects of TiO2 dose (0–2 g/l) and water matrix were analyzed. Besides, the comparison between mechanical coagulation-flocculation-decantation and simple decantation of TiO2 was carried out. The results show that simple decantation allowed the recovery of 97.5% of TiO2 Degussa P25 and TiO2 Levenger within 1 day of simple decantation, while applying the proposed mechanical coagulation-flocculation decantation 99.7% of recovery of both catalysts was achieved in 2 hours. Finally, the subsequent reuse of both catalysts was proved with little loss of efficiency in terms of photo-disinfection during the four cycles. Nevertheless, the standard TiO2 Degussa P25 photo-degradation efficiency of caffeine decreases considerably as compared to commercial suspension of TiO2 Levenger concerning the reutilization.

Idioma: Inglés

DOI: 10.1007/s11356-019-07276-3

Año: 2020

Publicado en: Environmental Science and Pollution Research 27 (2020), 9099–9113
ISSN: 0944-1344

Factor impacto JCR: 4.223 (2020)

Categ. JCR: ENVIRONMENTAL SCIENCES rank: 91 / 273 = 0.333 (2020) - Q2 - T2

Factor impacto SCIMAGO: 0.844 - Environmental Chemistry (Q2) - Pollution (Q2) - Medicine (miscellaneous) (Q2) - Health, Toxicology and Mutagenesis (Q2)

Financiación: info:eu-repo/grantAgreement/ES/DGA-FSE/T51-17R

Tipo y forma: Article (Published version)

Área (Departamento): Área Tecnologi. Medio Ambiente (Dpto. Ing.Quím.Tecnol.Med.Amb.)