TY - JOUR
T1 - Experimental study on visible-light induced photocatalytic oxidation of gaseous formaldehyde by polyester fiber supported photocatalysts
AU - Han, Zhenan
AU - Chang, Victor-Weichung
AU - Wang, Xiaoping
AU - Lim, Teik-Thye
AU - Hildemann, Lynn
N1 - cited By 22
PY - 2013
Y1 - 2013
N2 - Heterogeneous photocatalytic oxidation (PCO) has shown large potentials in controlling airborne gaseous pollutants such as volatile organic compounds (VOCs). This article addresses PCO of gaseous formaldehyde (HCHO) by VIS-active photocatalysts which were immobilized on polyester fiber filter through a spray coating method under room temperature. The coatings showed good dispersion and strong adhesion on the fiber surface as supported by the SEM images and the stability test result. High PCO efficiency was achieved by the spray-coated filter under typical room light illumination. The effects from various reaction parameters, such as volumetric flow rate, pollutant initial concentration, relative humidity, illumination strength, as well as photocatalyst loading amount, on the PCO efficiency were also evaluated systematically. A Langmuir-Hinshelwood model was used to examine the kinetics of VIS-PCO of HCHO. One of the important findings was that changes of relative humidity had little influence on the PCO efficiency at either low or high HCHO concentrations. Different from the UV-PCO process where hydroxyl radical (OH) is the major oxidative species, the VIS-generated holes, hVIS+, as well as the superoxide radical (O2-) were considered to contribute predominantly to the degradation of HCHO under visible light illumination. © 2012 Elsevier B.V.
AB - Heterogeneous photocatalytic oxidation (PCO) has shown large potentials in controlling airborne gaseous pollutants such as volatile organic compounds (VOCs). This article addresses PCO of gaseous formaldehyde (HCHO) by VIS-active photocatalysts which were immobilized on polyester fiber filter through a spray coating method under room temperature. The coatings showed good dispersion and strong adhesion on the fiber surface as supported by the SEM images and the stability test result. High PCO efficiency was achieved by the spray-coated filter under typical room light illumination. The effects from various reaction parameters, such as volumetric flow rate, pollutant initial concentration, relative humidity, illumination strength, as well as photocatalyst loading amount, on the PCO efficiency were also evaluated systematically. A Langmuir-Hinshelwood model was used to examine the kinetics of VIS-PCO of HCHO. One of the important findings was that changes of relative humidity had little influence on the PCO efficiency at either low or high HCHO concentrations. Different from the UV-PCO process where hydroxyl radical (OH) is the major oxidative species, the VIS-generated holes, hVIS+, as well as the superoxide radical (O2-) were considered to contribute predominantly to the degradation of HCHO under visible light illumination. © 2012 Elsevier B.V.
KW - Photocatalytic oxidation
KW - Visible light
KW - Formaldehyde
KW - Spray coating
U2 - 10.1016/j.cej.2012.12.025
DO - 10.1016/j.cej.2012.12.025
M3 - Article
SN - 1385-8947
VL - 218
SP - 9
EP - 18
JO - Chemical Engineering Journal
JF - Chemical Engineering Journal
ER -