Applicability of Titanium-Based Catalysts in the Photocatalytic Degradation of 2,3,7,8-Tetrachlorodibenzofuran

• Published in: Molecules (Basel, Switzerland) Switzerland), 2023-11, Vol.28 (22), p.7488
• Main Authors: Samara, Fatin, Darra, Rasha, Mohamed, Ahmed A., Ahmad, Waqas, Abu-Farha, Nedal, Lee, Haesung, Han, Changseok, Kanan, Sofian
• Format: Article
• Language: English
• Subjects: adsorbing material; Adsorption; Catalysts; Chemical reactions; Dibenzofurans; dioxin and furan derivatives; Dioxins; ELISA; Fourier transforms; GC/MS; Mass spectrometry; Methanol; Nanoparticles; Oxidation; Photocatalysis; Photodegradation; Scanning electron microscopy; Scientific imaging; Semiconductors; Silica; Silicon; Titanium; titanium-based catalysts; Toxicity; Toxicology
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules28227488

Polychlorinated dibenzofurans (PCDFs) are persistent toxic compounds that are ubiquitous in the environment. Nanocomposites of titanium(IV) oxide-vanadium(III) oxide (Ti3V2O7) and titanium(IV) oxide-silicon dioxide (Ti2Si7O30) were prepared and spectroscopically analyzed as potential decontaminants for dioxin-like materials. The analysis confirmed a homogeneous morphology with nanoscale particle size. The Ti-Si sample was found to have a high surface area compared to the Ti-V composite. Vanadium(III) oxide (V2O5) and silicon dioxide (SiO2) were chosen as materials for the formation of heterogeneous compounds with titanium(IV) oxide (TiO2) because they possess a suitable band alignment with TiO2, thus forming effective photocatalysts. This study evaluated the photodegradation of 2,3,7,8-tetrachlorodibenzo-furan (TCDF) in the presence of Ti-Si and Ti-V oxide composites, which was tested using high- (254 nm) and midenergy (302 nm) UV irradiation sources. While Ti-Si showed success in the photodegradation of 2,3,7,8-TCDF dissolved in a (1:1) methanol–tetrahydrofuran (MeOH-THF) solution, the Ti-V composite proved to be a powerful material in adsorbing TCDF with a high capacity immediately upon mixing. Ti-Si oxide was found to decompose TCDF under the two irradiation sources with 98–99% degradation occurring after 70 min. The use of 254 nm as an irradiation source in the presence of Ti-Si was 4.3 times faster than the analogue reaction irradiated without a catalyst. Byproducts of the degradation were evaluated using gas chromatography–mass spectrometry (GC–MS), resulting in a lower chlorinated congener and less toxicity, as the main degradation product.