| Titanium dioxide nanotubes (TNTs) were prepared and characterized with TEM, XRD and BET. The anatase products, with an external diameter of 5-7nm, a wall thickness of about 1nm and a length of 200-300nm, had a specific surface area of 276 m2·g-1. The COD removal by using O3/UV/TNTs in 60 minutes was 20.83% better than using O3/UV/P25, and 32.65% better than using O3/UV. In photocatalytic ozonation, 400℃was the best calcination temperature for TNTs.The best degradation of humic acid by O3/UV/TNTs was under the optimal condition, which was the temperature of 30℃, pH value of 8.5-10.7, titanium dioxide nanotubes dosage of 0.4 g/L, ozone dosage of 383.46 mg/h/L, and light intensity of 0.62 mW/cm2. A new kinetics model was established. In the model, the best reaction kinetics k was obtained under the condition with original pH value of 7.35, TNTs dosage of 0.806 g·L-1 and ozone dosage of 0.49 g·h-1·L-1. It was proved that radical reaction took the main role in humic acid degradation by O3/UV/TNTs. At high pH value, CO2 was easy dissolved in order to improve the original inorganic carbon (IC) and accumulate IC in process. And the IC was mainly CO32- and HCO3-, which had obvious inhibition to·OH. The pollution rate of catalyst was increased with reaction time extending, and reached maximum after a period of time. Then the pollution rate of catalyst would be bettered.The best catalytic acitivity of TiO2 nanotubes doped by aluminum (Al-TNTs) under visible light was under the optimal preparation condition, which was NaOH dosge of 19mL, Al2O3 dosage of 0.05g for 1.0g P25, Al2O3 form of powder and calcination temperature of 400℃. The response surface methodology (RSM) was used to study the effect of Al-TNTs/O3 under visible light on TOC removal. Original pH value showed the least effect on TOC removal. The other two factors affected TOC removal significantly. Al-TNTs dosage and ozone dosage had an obvious interaction.Al/TNTs was designed into a macroscopical product (M-Al/TNTs) and characterized by SEM, TEM and BET. The macrostructure of M-Al/TNTs was a cylinder with a diameter of 2 mm and a height of 3 mm, and the microstructure of it was a special structure of tubes with an external diameter of 5-7 nm, a wall thickness of about 1 nm and a length of 200-300 nm. The special surface area of M-Al/TNTs was about 153 m2·g-1 while that of Al/TNTs was about 220 m2·g-1. Treated by M-Al/TNTs/O3 under visible light, COD removal of landfill leachate solution was 59.27% when M-Al/TNTs was used for the first time, and 11.4% when it was used for the third time. Compared with 11.4%, COD removal of landfill leachate solution was 31.3% when the three-times-polluted M-Al/TNTs was regenerated by ozone in off-gas only. Ozone in off-gas revealed a significant advantage of the regeneration of M-Al/TNTs. A novel incorporate fluidized bed reactor for photocatalytic ozonation was designed, which contained pollution degradation and catalysts reuse. To degrade landfill leachate solution, the best dosge of M-Al/TNTs was 8g/L, and that of ozone was 582.12mg/h/L in this reactor.
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