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Analyzing the Photo-oxidation of 2-propanol at Indoor Air Level Concentrations Using Field Asymmetric Ion Mobility Spectrometry
Published on: June 14, 2018
Environmental ice photochemistry: monochlorophenols.
Jana Klánová1, Petr Klán, Jan Nosek
1RECETOX-TOCOEN, Masaryk University, Kamenice 126/3, 625 00 Brno, Czech Republic.
Environmental Science & Technology
|May 7, 2003
Summary
Photolysis of chlorophenols in ice primarily forms chlorobiphenyldiols via coupling reactions. At warmer temperatures, photosolvolysis yields hydroquinone and pyrocatechol, suggesting pollutant generation in cold environments.
Area of Science:
- Environmental Chemistry
- Photochemistry
- Atmospheric Chemistry
Background:
- Chlorophenols are common environmental pollutants.
- Photochemical reactions in cold environments are crucial for understanding pollutant fate.
- Halogenated phenolic compounds can be persistent, bioaccumulative, and toxic (PBTs).
Purpose of the Study:
- To investigate the photolysis of 2- and 4-chlorophenol in water ice.
- To identify phototransformation products and reaction mechanisms at low temperatures.
- To assess the potential for generating PBTs in cold ecosystems and the atmosphere.
Main Methods:
- Photolysis experiments conducted on 2- and 4-chlorophenol in water ice.
- Varying initial concentrations from 10(-7) to 10(-2) mol L(-1).
- Analysis of photoproducts at temperatures below and above -10 degrees C.
Main Results:
- Major phototransformations involved coupling reactions, forming chlorobiphenyldiols.
- No photosolvolysis occurred below -10 degrees C.
- At -5 degrees C, 4-chlorophenol yielded hydroquinone, and 2-chlorophenol yielded pyrocatechol, indicating photosolvolysis in a quasi-liquid layer.
Conclusions:
- Photochemistry in cold environments can generate significant amounts of PBTs from primary pollutants.
- These PBTs can be subsequently released into the broader environment.
- The findings support a model of pollutant generation in cold ecosystems and the upper atmosphere.
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