A novel photocatalytic reactor for the extended reuse of W-TiO2 in the degradation of sulfamethazine

Kareem Fouad; Mohamed Gar Alalm; Mohamed Bassyouni; Mamdouh Y Saleh

doi:10.1016/j.chemosphere.2020.127270

A novel photocatalytic reactor for the extended reuse of W-TiO₂ in the degradation of sulfamethazine

Chemosphere. 2020 Oct:257:127270. doi: 10.1016/j.chemosphere.2020.127270. Epub 2020 Jun 4.

Authors

Kareem Fouad¹, Mohamed Gar Alalm², Mohamed Bassyouni³, Mamdouh Y Saleh¹

Affiliations

¹ Department of Civil Engineering, Faculty of Engineering, Port Said University, Port Said, 42511, Egypt.
² Department of Civil and Environmental Engineering, Tokyo Institute of Technology, Meguro-ku, Tokyo, 152-8552, Japan; Department of Public Works Engineering, Faculty of Engineering, Mansoura University, Mansoura, 35516, Egypt. Electronic address: garalalm.aa@m.titech.ac.jp.
³ Department of Chemical Engineering, Faculty of Engineering Port Said University, Port Said, 42511, Egypt; Zewail University of Science and Technology, City of Science and Technology, October Gardens, 6 th of October, Giza, 12578, Egypt.

PMID: 32526466
DOI: 10.1016/j.chemosphere.2020.127270

Abstract

In this study, a photocatalytic reactor with a novel engineering design has been used for the extended degradation of sulfamethazine (SMZ). The reactor employed four consecutive stainless-steel plates immobilized by tungsten-dope TiO₂ (W-TiO₂) using polysiloxane. The characterization of W-TiO₂ by X-ray diffraction (XRD), Raman spectroscopy, and energy-dispersive X-ray (EDX) denoted successful doping of tungsten in the lattice of anatase crystals of TiO₂ suggesting a high photocatalytic activity under UV and visible light. A Box-Behnken experimental design was employed for the optimization of the operating parameters such as solution pH, flow rate, and the initial SMZ concentration. The residual SMZ concentration was below the detection limit after 30 min of the photocatalytic reaction under the optimum operating conditions. A highly remarkable degradation of SMZ was observed in five consecutive cycles, which reveals an extended stable photocatalytic activity offered by the reactor design. The transformation products were identified by tandem mass spectrometry, and they were employed to propose the degradation pathway. These results highlight the importance of using the photocatalysts in retained forms and open additional avenues for the practical application of photocatalysis in wastewater treatment.

Keywords: Antibiotics; Box-Behnken; Photocatalysis; Sulfamethazine; Transformation products.

MeSH terms

Catalysis
Light
Sulfamethazine / chemistry*
Titanium
Tungsten / analysis
Wastewater / analysis
Water Pollutants, Chemical / analysis
Water Pollutants, Chemical / chemistry*
X-Ray Diffraction

Substances

Waste Water
Water Pollutants, Chemical
titanium dioxide
Sulfamethazine
Titanium
Tungsten