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对静电纺丝法制备的TiO2和TiO2-V2O5纳米纤维进行光催化脱除模拟烟气中Hg0的研究。对纳米纤维进行了SEM、TEM、XRD、BET和UV-Vis检测。结果表明TiO2-V2O5纳米纤维为锐钛矿,V2O5高度分散在TiO2中。纤维直径在200nm左右,由粒径为10nm左右的微粒组成。掺杂V2O5后,纤维的吸光范围扩大,在可见光范围内的吸光度比纯TiO2时有了很大提高。实验研究了不同光照条件、V2O5的掺杂量和循环次数对脱汞的影响,分析了TiO2-V2O5催化脱汞的机理。当V2O5的质量含量为3%时,TiO2-V2O5在可见光下的脱汞率可达到66%,比纯TiO2时的7%有了显著提高;纤维的脱汞性能稳定,多次循环后紫外光和可见光下的脱汞率仍分别保持在80%和65%左右。电子的跃迁和电子、空穴的快速分离是TiO2-V2O5在可见光下脱汞率提高的主要原因。
Photocatalytic removal of Hg0 in flue gas from TiO2 and TiO2-V2O5 nanofibers prepared by electrospinning. The nanofibers were examined by SEM, TEM, XRD, BET and UV-Vis. The results show that TiO2-V2O5 nanofibers are anatase and V2O5 is highly dispersed in TiO2. Fiber diameter of about 200nm, the particle size of 10nm particles. After doping V2O5, the absorption range of the fiber is widened, and the absorbance in the visible range is much higher than pure TiO2. The effects of different light conditions, doping amount of V2O5 and number of cycles on mercury removal were experimentally studied, and the mechanism of the catalytic mercury removal by TiO2-V2O5 was analyzed. When the mass fraction of V2O5 is 3%, the mercury removal rate of TiO2-V2O5 under visible light can reach 66%, which is significantly higher than that of pure TiO2 at 7%. The mercury removal performance of the fiber is stable. After repeated cycles of UV light And mercury removal rate under visible light are still maintained at 80% and 65% respectively. Electron transitions and the rapid separation of electrons and holes are the main reasons for the increase of mercury removal rate of TiO2-V2O5 in visible light.