Electrospun metal oxide-TiO2 nanofibers for elemental mercury removal from flue gas.
Nanofibers prepared by an electrospinning method were used to remove elemental mercury (Hg(0)) from simulated coal combustion flue gas. The nanofibers composed of different metal oxides (MO(x)) including CuO, In(2)O(3), V(2)O(5), WO(3) and Ag(2)O supported on TiO(2) have been characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersing X-ray (EDX) and UV-vis spectra. The average diameters of these nanofibers were about 200nm. Compared to pure TiO(2), the UV-vis absorption intensity for MO(x)-TiO(2) increased significantly and the absorption bandwidth also expanded, especially for Ag(2)O-TiO(2) and V(2)O(5)-TiO(2). Hg(0) oxidation efficiencies over the MO(x)-TiO(2) nanofibers were tested under dark, visible light (vis) irradiation and UV irradiation, respectively. The results showed that WO(3) doped TiO(2) exhibited the highest Hg(0) removal efficiency of 100% under UV irradiation. Doping V(2)O(5) into TiO(2) enhanced Hg(0) removal efficiency greatly from 6% to 63% under visible light irradiation. Ag(2)O doped TiO(2) showed a steady Hg(0) removal efficiency of around 95% without any light due to the formation of silver amalgam. An extended experiment with 8 Hg(0) removal cycles showed that the MO(x)-TiO(2) nanofibers were stable for removing Hg(0) from flue gas. Factors responsible for the enhanced photocatalytic activities of the MO(x)-TiO(2) nanofibers were also discussed.
State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.
Yuan
Y
Yuan
Yongchun
Y
Zhao
Hailong
H
Li
Yang
Y
Li
Xiang
X
Gao
Chuguang
C
Zheng
Junying
J
Zhang
D000393:Air Pollutants / Q000737:chemistry* / Q000528:radiation effects; D000397:Air Pollution / Q000517:prevention & control; D003031:Coal; D008027:Light; D008628:Mercury / Q000737:chemistry* / Q000528:radiation effects; D057139:Nanofibers / Q000737:chemistry* / Q000528:radiation effects; D010087:Oxides / Q000737:chemistry* / Q000528:radiation effects; D011210:Power Plants; D014025:Titanium / Q000737:chemistry* / Q000528:radiation effects
D000393:Air Pollutants; D003031:Coal; D010087:Oxides; C009495:titanium dioxide; D014025:Titanium; D008628:Mercury