Abstract: Catalytic elimination of formaldehyde (HCHO) was investigated over
Cu-Al_2O_3 catalyst at room temperature.
The results indicated that no oxidation of HCHO into CO_2
occurs at room temperature, but the adsorption of HCHO occurs on the catalyst
surface. With the increase of gas hourly space velocity (GHSV) and inlet HCHO
concentration, the time to reach saturation was shortened proportionally. The
results of the in situ DRIFTS, Density functional theory calculations and
temperature programmed desorption (TPD) showed that HCHO was completely
oxidized into HCOOH over Cu-Al_2O_3 at
room temperature. With increasing the temperature in a flow of helium, HCOOH
was completely decomposed into CO_2 over the catalyst
surface, and the deactivated Cu-Al_2O_3
is regenerated at the same time. In addition, although Cu had no obvious
influence on the adsorption of HCHO on
Al_2O_3, Cu dramatically lowered the
decomposition temperature of HCOOH into CO_2. It was shown
that Cu-Al_2O_3 catalyst had a good
ability for the removal of HCHO, and appeared to be promising for its
application in destroying HCHO at room temperature.
Keywords: formaldehyde, Cu-Al[TeX:] _2O[TeX:] _3, in situ DRIFTS, TPD