The OES Diagnosis in Removal of HCHO by the Uniform Bipolar Nanosecond-Pulsed DBD Using Wire-Cylinder Electrode Configuration in Atmospheric N2

In this paper, the uniform bipolar nanosecondpulsed dielectric barrier discharge (NPDBD) with 15-ns rising time generating in a wire-cylinder reactor is employed to remove the gaseous formaldehyde in atmospheric pressure N
₂
. The image, the waveforms of pulse voltage and discharge current, the optical emission spectra of the discharges, and the removal rate of formaldehyde are recorded and calculated, respectively. It is found that the emission intensity of OH (A
²
Σ → X
²
Π, 0-0) rises when increasing the input power density (PD). Furthermore, with the increase of input PD and the emission intensity of OH (A
²
Σ → X
²
Π, 0-0), the removal rate of formaldehyde rises correspondingly. The results also indicate that when the O
₂
concentration rises within 0%-5%, the removal rate of formaldehyde increases, however, when the O
₂
concentration rises within 5%-20%, the formaldehyde removal rate decreases correspondingly. In addition, at the same conditions, the DBD synergistically removing formaldehyde with Al
₂
O
₃
and TiO
₂
could increase the removal rate by 10%-30% compared with the discharge only.