Catalytic Advanced Oxidation Processes for Sulfamethoxazole Degradation

Applied Sciences

CarlaA. Orge¹  Jéssica Martini¹  O.Salomé G. P. Soares¹  JoaquimL. Faria¹  M.Fernando R. Pereira¹ 

[1] Laboratory of Separation and Reaction Engineering–Laboratory of Catalysis and Materials (LSRE-LCM) Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto, Portugal;

关键词: catalytic ozonation;    photocatalysis;    hydrogen peroxide;    emerging pollutants;    carbon nanotubes;    titanium dioxide;   

DOI  :  10.3390/app9132652

来源: DOAJ

【 摘 要 】

The degradation of sulfamethoxazole (SMX) by several advanced oxidation processes (AOPs) is carried out in the presence of different catalysts. The catalysts used consisted of carbon nanotubes (CNT), titanium dioxide (TiO₂), a composite of carbon nanotubes and titanium dioxide (TiO₂/CNT), and iron supported on carbon nanotubes (Fe/CNT). SMX removal was evaluated by catalytic ozonation, photocatalysis, catalytic oxidation with hydrogen peroxide, and combinations of these processes. The evolution of the SMX concentration during reaction time, the mineralization degree, the toxicity of the treated solution, and the formation of organic intermediates and ions were monitored. Ozonation catalyzed by Fe/CNT and CNT and photocatalytic ozonation in the presence of CNT presented the fastest degradation of SMX, whereas photocatalytic ozonation with CNT showed the best results in terms of organic matter removal (92% of total organic carbon (TOC) depletion). Total mineralization of the solution and almost complete reduction of toxicity was only achieved in the photocatalytic ozonation with H₂O₂ and Fe/CNT catalysts. The compound 3-amino-5-methylisoxazole was one of the first intermediates formed during SMX degradation. p-Benzoquinone was only formed in photocatalysis. Oxalic and oxamic acids were also detected and in most of the catalytic processes they appeared in small amounts. Ion concentrations increased with the reaction time.

【 授权许可】

Unknown