In:
Atmospheric Chemistry and Physics, Copernicus GmbH, Vol. 22, No. 8 ( 2022-04-28), p. 5651-5663
Abstract:
Abstract. The reaction of hydroxyl radicals (OH) with 4-nitrophenol
(4NP) in an aqueous solution was investigated at pH = 2 and 9. The molar
yield of the phenolic products quantified was ca. 0.2 at pH = 2 and 0.4 at
pH = 9. The yield of 4-nitrocatechol (4NC) was higher at pH = 9. At the same time, a lower number of phenolic products was observed at pH = 9 due to
irreversible reactions of some phenols formed at pH 〉 7. Mineralization investigated with a total organic carbon (TOC) analyzer
showed that after 4NP was completely consumed, approximately 85 % of the
organic carbon remained in the aqueous solution. Moreover, as inferred from
the TOC measurements and the molar yields of the phenols formed, 65 % of
the organic carbon that remained in the aqueous solution was attributed to
the non-aromatic products. The light absorption of the reaction solution
between 250 and 600 nm decreased as a result of the OH reaction with 4NP.
However, the 4NP solution showed a noticeable resistance to the chemical
bleaching reaction investigated due to the formation of light-absorbing
by-products. This phenomenon effectively prolongs the timescales of the chemical bleaching of 4NP by OH by a factor of 3–1.5 at pH 2 and 9,
respectively. The experimental data acquired indicated that both photolysis
and the reaction with OH can be important processes for the removal of
light-absorbing organic compounds from cloud water particles containing 4NP.
Type of Medium:
Online Resource
ISSN:
1680-7324
DOI:
10.5194/acp-22-5651-2022
DOI:
10.5194/acp-22-5651-2022-supplement
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2022
detail.hit.zdb_id:
2092549-9
detail.hit.zdb_id:
2069847-1
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