Enhanced TiO2 photocatalytic degradation of bisphenol E by beta-cyclodextrin in suspended solutions.
Enhancement of beta-cyclodextrin (beta-CD) on TiO(2) photocatalytic degradation of bisphenol E (BPE, bis(4-hydroxyphenyl)ethane) was investigated under a 250 W metal halide lamp (lambda> or =365 nm) in this work. In the system of photocatalytic degradation of BPE, the photodegradation rate of BPE in aqueous solutions containing beta-CD and TiO(2) was obviously faster than that in aqueous solutions containing only TiO(2). After 40 min of irradiation, beta-CD could increase the photodegradation efficiency by about 26% for 10 mg l(-1) BPE in the UV-vis/TiO(2) system and the photodegradation of 2.5-20.0 mg l(-1) BPE in aqueous solutions was found to follow pseudo-first-order law and the adsorption constant and the reaction rate constant of BPE in the system containing beta-CD and TiO(2) are obviously higher than those in the system containing only TiO(2), the influence factors on photodegradation of BPE were studied and described in details, such as beta-CD concentration, pH, BPE initial concentration and gas medium. The formation of CO(2) as a result of mineralization of BPE was observed during the photodegradation process. After 120 min of irradiation, the mineralization efficiency of BPE reached 61% in the presence of beta-CD, whereas mineralization efficiency was only 23% in the absence of beta-CD. The enhancement of photodegradation of BPE could be dependent on the enhancement of adsorption of BPE on TiO(2) surface and moderate inclusion-depth of BPE in the beta-CD cavity.
Wang
Guanghui
G
School of Resources and Environmental Science, Wuhan University, PR China.
Wu
Feng
F
Zhang
Xu
X
Luo
Mingdao
M
Deng
Nansheng
N
D000327:Adsorption; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008903:Minerals / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010636:Phenols / Q000737:chemistry*; D010782:Photolysis; D012996:Solutions / Q000737:chemistry; D013057:Spectrum Analysis; D013535:Suspensions; D014025:Titanium / Q000737:chemistry*; D047392:beta-Cyclodextrins / Q000737:chemistry*
D008903:Minerals; D010636:Phenols; D012996:Solutions; D013535:Suspensions; D047392:beta-Cyclodextrins; C009495:titanium dioxide; D014025:Titanium