光催化技术在烟气脱汞领域的研究进展

Research Progress of Hg^(0) Removal from Flue Gas Using Photocatalytic Technology

汞是一种剧毒重金属,由于其在环境中的扩散及传播具有持久性和生物聚积性,致使汞污染已成为当今全球性急需解决的问题。针对燃煤电厂烟气Hg^(0)排放日益突出问题,综述了光催化技术脱除废气中Hg^(0)的研究现状,着重阐述了二氧化钛、卤氧化铋、金属掺杂半导体、非金属掺杂半导体等材料光催化脱除Hg^(0)的性能。由于二氧化钛能带较宽,可以采用金属或非金属掺杂的方式,提高其光催化氧化能力。由于卤氧化铋特殊的化学结构,它在可见光辐照下具有一定的光催化脱汞性能,采用贵金属、金属氧化物、非金属负载的方式可提高卤氧化铋的光催化脱汞性能。

Mercury is a highly toxic heavy metal.Due to its persistence and biological accumulation in the environment,mercury pollution has become a global problem that needs to be solved urgently.In view of the increasingly prominent problems of Hg^(0) emissions in coal-fired power plants,the development and research of low-temperature plasma technology for Hg^(0) removal is summarized.The performance of photocatalytic removal of Hg^(0) by photocatalyst materials such as titanium dioxide,bismuth halide oxide,metal doped semiconductor and non-metal doped semiconductor was emphatically stated.The results showed that the photocatalytic oxidation ability of TiO2 can be improved by metal or non-metal doping because of its wide energy band.Due to the special chemical structure of bismuth halide oxide,it possessed photocatalytic performances of mercury removal under visible light irradiation.The photocatalytic performance of bismuth halide oxide can be improved by means of the doping of precious metals,metal oxides and non-metal supports.