Photocatalytic Degradation of Pharmaceutical Trimethoprim in Aqueous Solution over Nanostructured TiO2 Film Irradiated with Simulated Solar Radiation

Abstract

Pharmaceuticals are characterized by a wide range of physical, chemical, and biological properties and functionalities that contribute to their inherent complexity as compounds. Unfortunately, human carelessness during the production, use, and disposal of these compounds results in their presence in the environment. This study utilized a nanostructured TiO2 film on a glass ring at the bottom of a reactor and simulated a solar radiation lamp as the radiation source for both photocatalytic and photolytic experiments, with the aim of unraveling the mechanism behind the degradation of trimethoprim (TMP), a pharmaceutical compound. This approach provides a novel perspective on the role of TiO2 in the degradation of pharmaceuticals and could pave the way for more efficient and sustainable wastewater treatment methods. Scavenger studies were carried out using isopropanol, ammonium oxalate, and triethanolamine to examine the photocatalytic mechanism. Isopropanol and triethanolamine were found to impede the photocatalytic degradation of TMP, highlighting the significance of hydroxyl radicals and positive holes in the degradation process, while no inhibition was observed in the presence of ammonium oxalate. The complete degradation of TMP through photocatalysis under simulated solar radiation was observed in ultra-pure water in fewer than 3 h, as indicated by the results. Our findings suggest that utilizing natural solar radiation as a source of UV-A radiation in reactor configurations based on this approach holds promise for cost-effective pharmaceutical degradation treatment in wastewater treatment plants. The practical potential of this approach is supported by the results obtained under simulated solar radiation with an irradiation intensity in the UV-A region of 33 ± 2 W/m2.

Engineering the Integration of Titanium and Nickel into Zinc Oxide Nanocomposites through Nanolayered Structures and Nanohybrids to Design Effective Photocatalysts for Purifying Water from Industrial Pollutants

“…It is known that a platy structure is the most common morphology for nanolayered structures, which are produced by building LDHs [1][2][3]. Scanning electron microscopy produced the images of the Ni-Zn-Ti LDH shown in Figure S1.…”

“…Photocatalytic processes are a kind of benign light-based technique whereby light is used as an energy source to excite photoactive materials and produce strong oxidizing agents that convert the organic pollutants to CO 2 and water. Previous studies of photocatalytic processes [1][2][3] concluded that the structure of the photocatalysts plays an important role in increasing their photo-related activities and the efficiency of the photocatalytic processes. Saber et al [1,2] designed novel nanohybrids based on inorganicmagnetic-organic structures for increasing the performance of photocatalysts to remove dyes from water.…”

“…Saber et al [1,2] designed novel nanohybrids based on inorganicmagnetic-organic structures for increasing the performance of photocatalysts to remove dyes from water. In addition, Ljubas et al [3] utilized nanostructured titanium oxide on a glass with a simulated solar radiation lamp for the complete removal of pharmaceutical compounds from water through photocatalytic processes.…”

Titanium Nanostructures: Advancing Photocatalysis in Complex Systems

“…Furthermore, the unique surface properties of TiO 2 nanoparticles, including their expansive surface area and the presence of surface defects, play a pivotal role in augmenting the efficiency of the photodegradation process. These attributes facilitate the adsorption of organic contaminants onto the nanoparticle surface, thereby enhancing the probability of interaction with photoexcited charge carriers and fostering degradation reactions [25,26].…”