Exploring the Influence\nof CeTiO<i><sub>x</sub></i> Morphology on Wet Catalytic\nOxidation Performance of Phenol\nover the Ru-Based Catalyst

Phenol is one of the predominant hazardous organic compounds\nfound\nin industrial wastewater. The use of catalytic oxidation technology\nto eliminate phenol has garnered significant interest due to its wide\napplicability and substantial economic benefits on an industrial scale.\nIn this paper, CeTiO<sub><i>x</i></sub> supports with different\nmorphology-supported Ru catalysts were tested in the CWAO of phenol\nand were characterized thoroughly using XRD, Raman, BET, NH<sub>3</sub>-TPD, H<sub>2</sub>-TPR, HR-TEM, and XPS techniques. The results\nsuggested that CeTiO<sub><i>x</i></sub>-NS and CeTiO<sub><i>x</i></sub>-NT exhibited superior performance in the\noxidation of phenol compared to CeTiO<sub><i>x</i></sub>-NP due to their enhanced redox properties, higher surface acidity,\nand more active oxygen content. Ru/CeTiO<sub><i>x</i></sub>-NS, Ru/CeTiO<sub><i>x</i></sub>-NT, and Ru/CeTiO<sub><i>x</i></sub>-NP had comparable COD conversion rates with values\nof 80.8%, 83.6%, and 79.1%, respectively. However, ruthenium aggregation\nwas observed on CeTiO<sub><i>x</i></sub>-NP, while Ru was\nwell-dispersed on CeTiO<sub><i>x</i></sub>-NT. Additionally,\nstronger interaction between Ru and support was indicated by the pronounced\nhydrogen spillover during the reduction of Ru/CeTiO<sub><i>x</i></sub>-NT and Ru/CeTiO<sub><i>x</i></sub>-NS. Ru/CeTiO<sub><i>x</i></sub>-NS demonstrated the best catalytic stability,\nwith only a 4.5% decrease in activity after five cycles. The resistance\nto carbon deposition and metal leaching of catalysts significantly\ninfluenced their stability, with carbon deposition identified as the\nprimary factor impacting the catalyst stability.