Sonophotocatalytic degradation of methyl orange by nano-sized Ag/TiO2 particles in aqueous solutions.
Sonophotocatalytic behaviour of methyl orange (MeO) in aqueous solution illuminated by light generated by a xenon lamp was investigated. For all three kinds of photocatalysts: Degussa P25 (75% anatase, 25% rutile, with a surface area of 55.07 m(2)/g), Yili TiO(2) (mainly anatase, with a surface area of 10.45 m(2)/g) and Ag/TiO(2) (silver loaded on Yili TiO(2)), the degradation followed pseudo-first order kinetics. The results showed a synergistic effect between sonolysis and photocatalysis. Some parameters affecting the sonophotocatalytic degradation of MeO with nanoparticles Ag/TiO(2) were determined. The results indicated that the degradation ratio of MeO increased with the increase of ultrasonic power. An optimum 60 mg/L of Ag/TiO(2) added to relatively low concentrations of MeO was proved to have the most effective degradation efficiency. The study on the effects of hydroxyl radical (*OH) scavengers (i.e. mannitol and dimethyl sulfoxide) on the MeO degradation indicated that *OH radicals played an important role during MeO degradation, which enhanced MeO to be completely decomposed.
Wang
Hongyuan
H
State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China.
Niu
Junfeng
J
State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China. Electronic address: junfengn@bnu.edu.cn.
Long
Xingxing
X
State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China.
He
Ya
Y
State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China.
D001391:Azo Compounds / Q000737:chemistry* / Q000528:radiation effects*; D002384:Catalysis; D016166:Free Radical Scavengers; D006863:Hydrogen-Ion Concentration; D017665:Hydroxyl Radical; D007202:Indicators and Reagents; D007700:Kinetics; D053758:Nanoparticles; D012834:Silver / Q000737:chemistry*; D012996:Solutions; D014025:Titanium / Q000737:chemistry*; D014867:Water; D014961:X-Ray Diffraction
D001391:Azo Compounds; D016166:Free Radical Scavengers; D007202:Indicators and Reagents; D012996:Solutions; D014867:Water; C009495:titanium dioxide; D017665:Hydroxyl Radical; D012834:Silver; C100258:methyl orange; D014025:Titanium