Laboratory studies of the impact of aerosol composition on the heterogeneous oxidation of 1-propanol

• Published in: Atmospheric environment (1994) Vol. 36; no. 1; pp. 149 - 156
• Main Authors: Oh, Sewon, Andino, Jean M
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 2002; Elsevier Science
• Subjects: 1-propanol; Applied sciences; Atmospheric pollution; Chemical composition and interactions. Ionic interactions and processes; Earth, ocean, space; Exact sciences and technology; External geophysics; Meteorology; OH radical reaction; Ozone; p-xylene; Pollutants physicochemistry study: properties, effects, reactions, transport and distribution; Pollution; Relative rate; Relative rate; OH radical reaction; Ozone; p-xylene; 1-propanol; Inorganic free radical; Sodium Sulfates; Troposphere; Air quality; Volatile organic compound; Photochemical reaction; Suspended particle; Atmospheric chemistry; Medium effect; Aerosols; Hydroxyl radicals; Air pollution; Oxidation; Ammonium Sulfates; Kinetics; Rate constant; Molecule radical reaction; Ammonium Chlorides; Ammonium Nitrates; Heterogeneous reaction; Sodium Chlorides
• ISSN: 1352-2310; 1873-2844
• DOI: 10.1016/S1352-2310(01)00412-5

The effects of (NH
4)
2SO
4, NH
4NO
3, NaCl, NH
4Cl, and Na
2SO
4 aerosols on the kinetics of 1-propanol oxidation in the presence of the hydroxyl radical have been investigated using the relative rate technique.
p-Xylene was used as a reference compound. Two different aerosol concentrations that are typical of polluted urban conditions were tested. The total surface areas of aerosols were 1400 (condition I) and 3400
μm
2
cm
−3 (condition II). Results indicate that aerosols promote the oxidation of 1-propanol, and the extents of the promoting effects depend on the aerosol composition and concentration. Increases in the relative rates of the 1-propanol/
OH reaction vs. the
p-xylene/
OH reaction were only observed for (NH
4)
2SO
4 aerosol conditions I and II, NH
4NO
3 aerosol condition II, and NH
4Cl aerosol condition II. These results indicate that NH
4
+ is the species promoting the oxidation of 1-propanol, and suggests the possibility of a strong interaction between NH
4
+ and 1-propanol that can change the activation energy of the initial
OH attack. These results have profound implications on the use of air quality models for the assessment of air pollution control strategies.