Effect of Formaldehyde on the Heterogeneous Reaction of Nitrogen Dioxide on γ-Alumina.
Heterogeneous reactions of NO2 on various mineral aerosol particles have been investigated in many previous studies, but a fundamental understanding of how the adsorption of formaldehyde influences the heterogeneous reactions of NO2 remains unclear. In this work, the effect of formaldehyde preadsorption on heterogeneous reaction of NO2 on the surface of γ-Al2O3 at 298 K and ambient pressure was investigated by using diffuse reflectance infrared Fourier transform spectrometry (DRIFTS). It was found that the preadsorption of HCHO on γ-Al2O3 could suppress the formation of nitrate, and the rate of nitrate formation decreased with increasing amount of preadsorbed HCHO, whereas the following heterogeneous uptake of NO2 could suppress the hydration reaction of HCHO and promote the production of HCOO(-) during the reaction. Surface nitrite was formed and identified to be an intermediate product and gradually disappeared as the reaction proceeded. The amount of the formed nitrite decreased when the amount of HCHO increased. Uptake coefficients of heterogeneous reactions were calculated and found to be sensitive to the adsorption of HCHO. A possible mechanism for the influence of HCHO adsorption on the heterogeneous conversion of NO2 on γ-Al2O3 was proposed, and atmospheric implications based on these results were discussed.
Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University , Shanghai 200433, China.
Zhenyu
Z
Sun
Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University , Shanghai 200433, China.|Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology , Nanjing 210044, China.
Lingdong
L
Kong
Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University , Shanghai 200433, China.
Xi
X
Zhao
Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University , Shanghai 200433, China.
Xiaoxiao
X
Ding
Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University , Shanghai 200433, China.
Hongbo
H
Fu
Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University , Shanghai 200433, China.
Tiantao
T
Cheng
Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University , Shanghai 200433, China.
Xin
X
Yang
Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University , Shanghai 200433, China.
Jianmin
J
Chen