GEOC 68 |
| The degradation of low-level formaldehyde gas was studied by using UV/TiO2/O3 process in the well-sealed room controlled by air-conditioning systems. The effects of initial formaldehyde concentration , humidity, initial formaldehyde concentration and the amount of ozone applied on degradation of formaldehyde gas were investigated. Formaldehyde degradation by UV/TiO2/O3 process can be higher than 97% and the formaldehyde residue (0.04 mg/m3) is below the WHO guideline (0.1 mg/ m3), while with UV/TiO2 process the degradation of formaldehyde from 68.5% to 87.5%, the formaldehyde residue from 0.52 to 1.82 mg/m3. Formaldehyde degradation can be higher than 97% with the relative humidity between 20% to 45% and the formaldehyde degradation is still more than 83% with the relative humidity increase to 75% by UV/TiO2/O3 process. The highest degradation in UV/TiO2 process is only 68% occured at a relative humidity of 30%. The influence of five kinds of processes on formaldehyde's degradation was compared and the effect of ozone amount was studied at the same time. The experimental results indicated that addition of ozone can considerably increase decomposing of formaldehyde, and combination of ozonation with photocatalytic oxidation on formaldehyde showed a synergetic effect. |
|
Geochemistry Poster Session
6:00 PM-8:00 PM, Wednesday, August 22, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Geochemistry |