摘要
Electrochemical heterogeneous catalytic ozonation(E-catazone) is a promising and advanced oxidation technology that uses a titanium dioxide nanoflower(TiO_(2-NF))-coated porous Ti gas diffuser as an anode material.Our previous study has highlighted that the importance of the TiO_(2-NF)coating layer in enhancing*OH production and rapidly degrading O_(3)-resistant drugs.It is well known that the properties of TiO_(2-NF)are closely related to its sintering temperature.However,to date,related research has not been conducted in E-catazone systems.Thus,this study evaluated the effect of the sintering temperature on the degradation of the O_(3)-resistant drug para-chlorobenzoic acid(p-CBA) using both experimental and kinetic modeling and revealed its influence mechanism.The results indicated that the TiO_(2-NF)sintering temperature could influence p-CBA degradation and*OH production.TiO_(2-NF)prepared at 450 C showcased the highest p-CBA removal efficiency(98.5% in 5 min) at a rate of 0.82 min^(-1),and an*OH exposure of 8.41 x 10^(-10) mol L^(-1) s.Kinetic modeling results and interface characterization data revealed that the sintering temperature could alter the TiO_(2) crystallized phase and the content of surfaceadsorbed oxygen,thus affecting the two key limiting reactions in the E-catazone process.That is,≡TiO_(2) surface reacted with H_(2) O to form TiO_(2)-(OH)_(2),which then heterogeneously catalyzed O_(3) to form *OH.Consequently,E-catazone with a TiO_(2-NF)anode prepared at 450°C generated the highest surface reaction rate(5.00 x 10^(-1) s^(-1) and 4.00 x 10^(-3) L mol^(-1) s^(-1),respectively),owing to its higher anatase content and adsorbed oxygen.Thus,a rapid O_(3)-TiO_(2) reaction was achieved,resulting in an enhanced*OH formation and a highly effective p-CBA degradation.Overall,this study provides novel baseline data to improve the application of E-catazone technology.
基金
supported by the Beijing Outstanding Young Scientist Project (No.C19H100010)
Beijing Outstanding Talent Training Foundation,China (No.2018000020124G056) with title ‘Efficient removal and toxicity study of typical antibiotics from waste water of high-speed railway trains in Beijing’
the National Natural Science Foundation of China (No.52042201)。
