Photocatalytic Properties of Commercially Available TiO2: Study of Fotosan® and InterBrasil® FA-101 for H2S Degradation Using UV and Solar Radiation

Abstract

This paper proposes the study and comparison of two commercial photocatalysts of TiO2 when applied as coating on a fibrocement roof tile. Are reported their respective photocatalytic activities, chemical, morphological, and textural characteristics. For that, commercial photocatalysts InterBrasil® FA-101 and Fotosan® were deposited on fibrocement support to perform photocatalytic activity tests and characterization analyses. The measurement of the photocatalytic activity of each sample was carried out through the efficiency of H2S degradation, using artificial (UV lamp) and natural (solar lighting) radiation. The surfaces formed with this photocatalyst coating were characterized by scanning electron microscopy, with energy-dispersive X-ray spectroscopy (SEM-EDX), X-ray diffraction (XRD), nitrogen adsorption-desorption isotherms, diffuse reflectance spectroscopy (DRS), and Fourier infrared transformation using attenuated total reflection (ATR-FTIR). The volumetric flow rate and saturation time (deactivation) were evaluated as operational performance parameters of the degradation reaction. The X-ray diffraction shows that TiO2 formed in the coatings correspond to the anatase phase. In addition, the pore volume of the coatings was from 4.9 to 9.0 × 10−3 g cm−3 and the superficial area was from 19.6 to 30.5 m2 g−1 that is considered relatively high. The results showed that, unlike the Fotosan®, the type of radiation used had a greater influence on the InterBrasil® FA-101, since there was a reduction of the photocatalytic activity when the solar radiation was used. The H2S degradation efficiency of 80% was obtained for a residence time (RT) of 115 s using Fotosan®, whereas that for InterBrasil® FA-101 was reached 45% for the same RT. Lower on the photocatalytic activity was observed after 30 min and 390 min of reaction for the InterBrasil® FA-101 and Fotosan®, respectively. The sample containing Fotosan® was the most effective photocatalyst in comparison with InterBrasil® FA-101.