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Titanium dioxide (TiO2) having a good chemical stability, wear resistance, and low cost, no toxic to the human body and the majority of contaminants have higher light catalytic activity and other characteristics, and is widely used as a photocatalyst. However, the presence of TiO2 photocatalyst photoresponse small range of photon utilization is low, direct application of its powder catalyst difficult to separate. Butyl titanate (Ti (OR) 4) as the precursor, the sol - gel (sol-gel) method, Fe, N ion doped modified substances, activated carbon (AC) and activated carbon fiber (ACF ) as the carrier prepared TiO2 composite photocatalyst. - Toluene gas-phase photocatalytic degradation experiments of catalyst preparation process (ion doping amount, type of inhibitor, calcination temperature, TiO2 loading vector species) of volatile organic compounds (VOCs) and application conditions (pollutants concentration, catalyst cycle number and use) the impact of its performance; investigated its performance degradation of acetone and formaldehyde. The results showed that the AC for the carrier, the amount of ion doping N 8%, Fe 8%, and acetic acid as the inhibitor, the highest activity of 500 ° C and calcined for 2 h obtained TiO2/AC composite photocatalyst (up more than 90%); the use of the same catalyst, the optical activity of the catalyst of the ACF load higher than that of the AC load photocatalyst (toluene degradation rates were 94% and 72%); With the increase in the initial concentration of toluene, the AC load photocatalyst the degradation rate of the toluene increases, there is no replacement of the catalyst deactivation phenomenon. With increasing cycle times of TiO2/AC the photocatalytic activity is gradually reduced, but the cycle 6 times, of TiO2/AC the activity is still higher than the P-25; TiO2/ACF composite photocatalyst reused six times, and the light basically unchanged; catalytic activity and the use of the same binder (sodium silicate), toluene photocatalytic degradation rate increases with the increase in the amount of the composite photocatalyst. Degradation of the performance of different VOCs study found, 120 min, the composite photocatalyst degradation rate of toluene and acetone are about 90%, compared with 35% in the degradation rate of formaldehyde. Observed by scanning electron microscopy (SEM), most of TiO2 granular embedded in the AC pores, while the form of a film-coated surface of the ACF; X-ray diffraction (XRD) studies have shown that AC supported TiO2 prepared photocatalyst are anatase, calcination temperature and carrier types anatase content greater impact; ultraviolet - visible (UV-Vis) spectrophotometric analysis found, Fe, N ion co-doped TiO2 on visible light response and AC load TiO2 composite photocatalyst dual enhanced absorption in the visible and ultraviolet region. Typical VOCs photocatalytic reaction kinetics studies have shown that the degradation of toluene, acetone and formaldehyde in on TiO2/AC composite photocatalyst model of first-order kinetics: ln [1 / (1-X)] = kt; pollutants early initial concentration and the composite photocatalyst usage of toluene photocatalytic degradation kinetics have a certain influence.
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