[Application of nano-sized TiO2 photocatalysis to air purification and sterilization].
OBJECTIVE
To develop and evaluate the efficiency of air purification and sterilization instrument based on nano-sized TiO(2) photocatalytic technique.


METHODS
The nano-sized TiO(2) photocatalytic air purification and sterilization instrument was designed and a sample had been prepared. The sterilization efficiencies for E.coli and Klebsiella by the nano-sized TiO(2) photocatalytic instrument and ultraviolet (UV) were measured in closed labs. The on-site efficiency of the instrument was evaluated, too.


RESULTS
The nano-sized TiO(2) photocatalytic air purification and sterilization instrument was composed of five units: rough filter, nano-sized TiO(2) photocatalytic unit, activated carbon fiber filter, negative ion generator, and programmed control unit. The E.coli killing rates by the nano-sized TiO(2) photocatalytic instrument were 76.0%, 81.8%, 77.5%, and 80.7% at 30, 60, 90, and 120 minutes, respectively. There was no significant difference between the E.coli killing rates of the instrument and UV (P > 0.05), except the 120 minutes timepoint. The Klebsiella killing rates by the instrument were 78.4%, 79.5%, 67.3%, and 58.5% at 30, 60, 90, and 120 minutes, respectively. The Klebsiella killing efficiencies of the instrument at 30 and 60 minutes were better than that of UV (P < 0.01). There was no significant difference between the Klebsiella killing efficiencies of the instrument and UV (P > 0.05).


CONCLUSIONS
The air sterilization efficiency of the nano-sized TiO(2) photocatalytic instrument should be equivalent or better as compared with the UV. This instrument might be used for the air purification and sterilization of the public locations.
Li
Bing-jie
BJ
101 Institute, Ministry of Civil Affairs, Beijing 100070, China.
Yang
De-hui
DH
Wu
Shuai-qin
SQ
Li
Bo-sen
BS
Meng
Hao
H
Jiang
Si-peng
SP
Liu
Guo-jun
GJ
Zhao
Yue-hui
YH
Cui
Hong-bo
HB
Zhou
Xue-mei
XM
Zhong
Zhao-hua
ZH
D000397:Air Pollution / Q000517:prevention & control*; D003666:Decontamination / Q000379:methods*; D004203:Disinfection / Q000379:methods*; D049329:Nanostructures; D010777:Photochemistry; D014025:Titanium
C009495:titanium dioxide; D014025:Titanium