Photocatalytic degradation of atrazine by an N-doped TiO2/polymer composite: catalytic efficiency and toxicity evaluation. Issue 4 (August 2022)

• Record Type: Journal Article
• Authors: Navarra, Wanda; Sacco, Olga; Daniel, Christophe; Venditto, Vincenzo; Vaiano, Vincenzo; Vignati, Davide Anselmo Luigi; Bojic, Clément; Libralato, Giovanni; Lofrano, Giusy; Carotenuto, Maurizio
• Is Part Of: Journal of environmental chemical engineering. Volume 10:Issue 4(2022)
• Publication Date: 2022-08
• Subjects: Atrazine -- Polymeric aerogel -- N-doped TiO2 -- Photocatalysis -- Ecotoxicity; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2022.108167
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: Monolithic composite aerogel based on N-doped TiO2 (NdT) photocatalyst dispersed into syndiotactic polystyrene (sPS) matrix was used for atrazine (ATZ) degradation under ultra-violet (UV) and visible light (Vis) irradiation. sPS/NdT composite aerogel, with a polymer/photocatalyst 90/10 wt ratio, was achieved by super critical CO2 extraction of chloroform from the relative sPS/NdT gel. Testing of the sPS/NdT photocatalytic activity was performed by using initial ATZ concentration of 0.1 mg/L and a sPS/NdT composite in monolithic aerogel form. ATZ removal was equal to 47% and 25% under UV or Vis light, respectively, after 180 min of irradiation. The efficiency of the photocatalytic process was also investigated by monitoring the ecotoxicity of the treated water to Aliivibrio fischeri, Raphidocelis subcapitata, and Daphnia magna . The results indicated that, for both UV and Vis irradiation, even for high ATZ removal efficiency (i.e., UV treatment), the toxicity of process effluent is greater than the initial one, most likely because of the generation of toxic by-products. The UV treatment was effective only after 72 h when the solution appeared not toxic to D. magna and presented a very low effect to R. subcapitata . On the other hand, under Vis light irradiation, a very high level of toxicity was still detected after 72 h of treatment time. Toxicity tests are confirmed as an indispensable tool for a correct assessment of the environmental impact of water treatment processes. Graphical Abstract: ga1 Highlights: Effective synergy between NdT and sPS aerogel was observed. sPS/NdT was always more active in the atrazine degradation than NdT powder. Degradation kinetic of atrazine was independent from its initial concentration. Photocatalytic activity of sPS/NdT not decreased after five reusability tests. After 72 h no or low toxicity was observed under investigated treatments.