| photocatalytic and activated carbon adsorption were useful method of potable water deep purification. TiO2 photocatalytic technology can degrade most organic pollutants in the water, and kill off common pathogenic microorganism. But the range of light absorb of TiO2 was narrow and the utilization ratio of sun light was low, which can not reach the intention for purifying water. Mesoporous modified and nonmetal doping were useful to settle the above-mentioned problems. Activated carbon supported silver could effectively kill off bacteria in the water, but its antibacterial activity was price of losing Ag+, the technology of controlling and releasing Ag slowly was difficulty to realize at present. Based on these, this paper prepared mesoporous TiO2 by template method, and TiO2 doping nonmetal composite with activatd carbon(AC). High specific surface area and strong pore structure of AC can enrich microorganism in the surface of AC partly becoming high concentration, improving photocatalysis reaction rate of TiO2.Mesoporous TiO2 was prepared by two-step calcinations as Cetyltrimethylammonium bromide (CTAB) for the template. Crystal structure and pore structure of TiO2 was characterized. The results showed that the prepared TiO2 had the typical mesoporous structure, and the most probable pore size was 7.2 nm, having the adsorption isotherm of typeⅣ. XRD results showed that the sample after two-step calcination had completely crystallized into anatase phase structure, and its grain size was between 10-12 nm. FT-IR spectra confirmed that the template of samples had been completely removed after two-step calcination. Photocatalytic activity of the samples was tested using phenol solution as a model reactant, arid the dosage of template was 3.3%. The samples calcined at 150℃for 2 h and programmed to 500℃for 2 h could adsorb 6.14% phenol for 30 min in the dark. After reaction for 140 min, the degradation rate of phenol was 54.1%. Mesoporous structure of TiO2 increased adsorption, but photocatalytic activity had no significant increase.A visible-light response activated carbon (TiN/GAC) with antibacterial activity was prepared by calcinations of the mixture of TiO2 precursor obtained by acid catalyzed hydrolysis method and commercial granular activated carbon(GAC) in NH3/N2 atmosphere. The antibacterial activity of the prepared activated carbon towards E. coil was investigated under the visible-light irradiation. X-ray diffraction(XRD), Scanning electron spectroscopy(SEM), Fourier transform infrared spectroscopy(FTIR) and N2 adsorption analyser were used to characterize the crystal phase structure, surface morphology, spectral characteristics and pore properties. The results show there is no influence for crystal phase structure of TiO2 supported AC, remaining anatase phase. According to the Scherrer formula, crystal particle size of TiO2 was 9.8nm. Non-crystal phase layer and strong adsorption force of carrier can inhibit the grain growth of TiO2, and AC combines with TiO2 in Ti-O-C so that TiO2 formestight film on AC. The sample calcinated at 500℃for 5 h exhibites the highest bactericidal performance, and the bactericidal rate reached up to 67% after 4 h irradiation, which was better than that of nature light in the same condition. |
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