[Fe-Ti Co-Doped Alumina-Induced Surface Dual Reaction Center for Catalytic Ozonation to Remove Pollutants from Water].

Multiphase catalytic ozone oxidation technology has received wide attention for its effectiveness in removing organic pollutants from water. However, the existence of a rate-limiting step in the metal oxide-catalyzed ozonation process based on single-site redox, which inhibits the activity, greatly limits the practical application of the multiphase catalytic ozonation technology. To solve this bottleneck problem, lattice doping of metal oxide γ-Al2O3 substrates with transition metal species Fe and Ti was used to prepare novel dual reaction center catalysts (FT-A-1 DRCs). Characterization of their morphological structures and chemical compositions was conducted by XRD, TEM, XPS, and other techniques, and it was demonstrated that the lattice substitution of Fe and Ti for Al resulted in the formation of surface-poor electron-rich microregions (electron-rich Fe microcenters and electron-deficient Ti microcenters). The FT-A-1 DRCs were used to catalyze the odor oxidation process and exhibited excellent activity and stability for the removal of a range of non-degradable organic pollutants, such as ibuprofen. The interfacial reaction mechanism was revealed using EPR and electrochemical techniques. It was found that in the catalytic odor oxidation process, O3/H2O was directionally reduced at the electron-rich microcenters to produce·OH, whereas the contaminants could be oxidized at the electron-deficient microcenters as electron donors to continuously supply electrons to the reaction system. This reaction process utilizes the pollutant's own energy to achieve two-way degradation of the pollutant (·OH attack and direct electron donor), thereby overcoming the rate-limiting step in the metal-oxide-catalyzed ozone oxidation process.