Res. Chem. Intermed.
, Vol. 32, No. 1, pp. 9–16 (2006)
Also available online - www.vsppub.com
Experimental study of photocatalytic oxidation of
formaldehyde and its by-products
, XIAOJIANG YE
, YUANGAO WEN
and WENFENG SHANGGUAN
School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
Merchant Marine College, Shanghai Maritime University, Shanghai 200135, China
Received 18 September 2004; accepted 16 March 2005
Abstract—Formaldehyde is one of the most harmful pollutants that endanger occupants’ health
and the way of its effective removal has become a focus in the ﬁeld of air quality. This paper
studies the static photocatalytic removal of formaldehyde experimentally and ﬁnds out that carbon
monoxide, which is more harmful to occupants’ health than the formaldehyde itself, is one of the by-
products in the process of photocatalytic oxidation of formaldehyde. The increase of carbon monoxide
concentration should be taken into consideration in the photocatalytic application. The photocatalyst
surface at room temperature can weakly adsorb CO and CO
, which can deactivate the photocatalysts.
Keywords: Formaldehyde; photocatalysis; carbon dioxide; carbon monoxide; titanium dioxide.
The widespread presence of formaldehyde (HCHO) in the environment poses a
serious environmental challenge because formaldehyde is carcinogenic, toxic and
extremely persistent in the environment. Formaldehyde is more difﬁcult to remove
than other air pollutants because of its physical and chemical properties.
Photocatalysis is an emerging and promising technology for pollution remediation
and has been demonstrated as an efﬁcient abatement technology for the oxidation
of volatile organic compounds at ambient temperature and pressure conditions
[1–4]. Therefore, the application and validity of photocatalysis on the removal
of formaldehyde in air has aroused great interest.
Among the studied photocatalysts, titanium dioxide (TiO
) is considered to
be relatively inexpensive, chemically stable and it has been extensively studied
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