| Water pollution is always the most considered environmental problem, the industry waste water, living waste water and medical waste water are main polluted source. Especially the dye waste water, which has dark coloure, great toxicity and complex component, is difficult to treat. The medical waste water which contained antibiotic can result in negative influences, and it is directed to influence the environmental zoology and health of the living, so it is more and more attented by us. The treated methods of waste water mainly included physics, chemical, biochemical, et al. The tradiational technology of treated the waste water were always high cost or seconded pollution can not reach the better results. Semiconductor Photocatalysis which belonged advanced oxided technology is one friendly environmentally technology, and may be the ideally realized clear removal pollutant. TiO2 photocatalyst, as one friendly materials, is widely used for treated the waste water and waste gas, and prepared the self-clean products. But TiO2 has limitation, such as the adsorbted light limited UV range, low photons efficiency and lacked selectivity. Thus, the devolopment of strong respond to visible light, high photocatalytic activity and choice new photocatalysts is the hot research.Herein, we chose the fly-ash cenospheres as the carrier and prepared TiO2/fly-ash cenospheres the photocatalyst. Then the loaded catalyst was modified by surface sensitization method which could improve the responds for visible light, and it was enhanced the choice via surface imprinted technology.The work mainly included the following items:I Preparaton of sensitized TiO2/fly-ash cenospheres and degradation of waste dyea. Cobalt Sulfophthalocyanine (CoPcS) sensitized TiO2 Sol samples were prepared through a Sol-Gel method using cobalt sulfophthalocyanine as a sensitizer. Loading and modified floating photocatalyst was prepared by hydrothermal method using fly-ash cenospheres as a carrier. The properties of the samples were characterized by Scanning electron microscopy(SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and UV-vis diffuse reflectance spectrum (DRS). Photocatalytic activity was studied by degrading waste water of methylene blue under visible light. The results indicate that the fly-ash cenospheres are covered by modified TiO2 film which composed of the anatase, brookite and rutile mischcrystal phase. CoPcS/TiO2/fly-ash cenospheres samples have good catalytic activity under visible light, and have strong absorbency during 600-700nm. The sensitization of CoPcS can enhance visible light catalytic activity of TiO2/Fly-ash cenospheres. The degradation rate of methylene blue reaches 73.36% in 180 min under the visible light illumination. But too much CoPcS can decrease its catalytic activity.b. AgCl/TiO2/fly-ash cenospheres photocatalysts were prepared by a simple sol-gel method. The catalysts were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), thermo gravimetric analysis-differential scanning calorimeter (TG-DSC), and UV-vis diffuse reflection spectrum (UV-vis DRS). The results show that the fly-ash cenospheres are coated with about 2μm thickness of AgCl/TiO2 nano-composite films. The fly-ash cenospheres loaded the films of AgCl/TiO2 photocatalysts exhibit high visible-light-induced photocatalytic activity for the decomposition of Rhodamine B waste water. When the photocatalyst contained the dosage of 0.21 g AgCl, the photo-degradation rate could reach 94.96% in 180 min under visible light irradiation, and removal rate of TOC could reach 20.34% in the same condition.c. The TiO2/fly-ash cenospheres were prepared via sol-gel method, and the surface of TiO2/fly-ash cenospheres was further modified by hydrogen peroxide (H2O2). Scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-vis diffuse reflectance spectra (UV-vis DRS), photoluminescence (PL) and X-ray photoelectron spectroscopy (XPS) were applied to characterize structure, performance and chemical composition of as-prepared samples. The photocatalytic activity of as-prepared samples was evaluated by degradation of methylene blue under visible light irradiation. The results indicate that the modified phototcatalyst of TiO2/fly-ash cenospheres is effectively improved the absorption of light. The photocatalytic degradation of methylene blue is enhanced under visible light irradiation, which the degradation rate is higher 42.5%than the untreated TiO2/fly-ash cenospheres with H2O2. Moreover, the simple way to modified TiO2/fly-ash cenospheres and enhancing the photocatalytic activity is better for practical application.ⅡPreparation of modified photocatalyst via conductive polymer and degradation of antibiotic waste watera. A series of Poly-o-phenylenediamine/TiO2/fly-ash cenospheres (POPD /TiO2/fly-ash cenospheres) composites have been prepared from o-phenylenediamine and TiO2/fly-ash cenospheres under various polymerization conditions. The properties of the samples were characterized by scanning electron microscopy(SEM), energy dispersive spectroscopy (EDS), specific surface area (BET), X-ray diffraction (XRD), fourier transform infrared (FT-IR) and UV-vis diffuse reflectance spectrum (UV-vis DRS). Photocatalytic activity was studied by degradation of antibiotics waste water under visible light. The results indicate that the photo-induced method is viable for preparing modified photocatalysts, and the modified photocatalysts have good absorption in visible light range. The photocatalysts of POPD/TiO2/fly-ash cenospheres which have good performance are prepared at pH=3 and pH=4, and the polymerized time around 40 min. When the photocatalysts are prepared under the conditions of pH=3 and polymerized time 40 min, the degradation rate of roxithromycin waste water could reach near 60%, and it indicates that the way of POPD modified TiO2/fly-ash cenospheres to degrade the antibiotics waste water is viable.b. Porous-TiO2/fly-ash cenospheres were prepared via sol-gel with a traditionary surfactant hexadcetyltrimethylammonium bromide (CTAB) as template. The as-prepared porous materials were further modified by the poly o-phenylenediamine (POPD) with photo-induce method. The as-prepared photocatalysts were characterized by XRD, Raman, SEM, UV-vis DRS, FT-IR analyses. The photocatalytic activity was studied via degradation of ciprofloxacin antibiotic waste water under visible light irradiation. The results indicate that porous materials is well formed, the photocatalytic activity of photocatalyst is enhanced with modified POPD. The degradation rate of POPD/porous-TiO2/fly-ash cenospheres could reach 71.36%which improved near 36%than the degradation rate of TiO2/fly-ash cenospheres. It clearly shows that the properties of porous and POPD modification could effectively increase the photocatalytic activity.ⅢPreparation surface imprinted photocatalysts and degradation of antibiotic waste watera. Fe2+/Fe3+@P-OPD/TiO2/fly-ash cenospheres photocatalysts has been successfully prepared by ions imprinting technology. The as-prepared ions imprinting photocatalysts have been characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM), UV-vis diffuse reflectance spectra (UV-vis DRS) and Fourier transform infrared (FT-IR). The photocatalytic activity of the samples was studied by the degradation of ciprofloxacin antibiotics waste water under visible light irradiation. The results showed that the iron ions imprinting photocatalysts could effectively promote the mutual transformationbetween Fe2+and Fe3+, increased the separation rate of photoelectrons and holes in the cycling system, and so improved the photocatalytic activity of photodegradation system on the ciprofloxacin antibiotics.. The photodegradation rate could reach 80 % in 50 min under visible light irradiation. According to our experimental results, a mechanism of preparation and photodegradation system of ions imprinting photocatalyst was also proposed.b. The surface molecular imprinted photocatalyst of TiO2/fly-ash cenospheres was prepared by molecular imprinted technology with ciprofloxacin as the template. The imprinted photocatalyst was further characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), UV-vis diffuse reflectance spectra (UV-vis DRS) and Fourier transform infrared (FT-IR). The preferential choice and activity of imprinted photocatalyst was evaluated by degradation of antiobic waste water. The results indicate that the surface imprinted photocatalyst could effectively preferential degradation of template molecular and enhance the photocatalytic activity. The degradation rate of molecular could reach 70% in 60 min under visible light irradiation. The degradation coefficient of relatively selectivity could reach 3.5299 compared with the tetracycline. The degradation intermediate product of ciprofloxacin was further discussed.c. The molecular/ion surface imprinted TiO2/fly-ash cenospheres photocatalyst was prepared by molecular imprinted technology with La3+and oxytetracycline. The phase, surface structure and light absorption of as-prepared photocatalyst were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), UV-vis diffuse reflectance spectra (UV-vis DRS) and Fourier transform infrared (FT-IR). The preferential choice and activity of imprinted photocatalyst was evaluated by degradation of antibiotic waste water. The results indicate that molecular/ion surface imprinted photocatalyst could effectively preferential degradation of template molecular and enhance the photocatalytic activity. The degradation rate of molecular could reach 76% in 60 min under visible light irradiation. The degradation coefficient of relatively selectivity could reach 4.5146 compared with the ciprofloxacin.
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