Journal
ENVIRONMENTAL SCIENCE & TECHNOLOGY
Volume 46, Issue 7, Pages 3912-3920Publisher
AMER CHEMICAL SOC
DOI: 10.1021/es300142y
Keywords
-
Categories
Funding
- NSF [OCE 1032223, OCE 0648414]
- Division Of Ocean Sciences
- Directorate For Geosciences [1032223] Funding Source: National Science Foundation
Ask authors/readers for more resources
To probe the mechanism of the photosensitized loss of phenols by humic substances (HS), the dependence of the initial rate of 2,4,6-trimethylphenol (TMP) loss (R-TMP) on dioxygen concentration was examined both for a variety of untreated as well as borohydride-reduced HS and C-18 extracts from the Delaware Bay and Mid-Atlantic Bight. R-TMP was inversely proportional to dioxygen concentration at [O-2] > 50 mu M, a dependence consistent with reaction with triplet excited states, but not with O-1(2) or RO2. Modeling the dependence of R-TMP on [O-2] provided rate constants for TMP reaction, O-2 quenching, and lifetimes compatible with a triplet intermediate. Borohydride reduction significantly reduced TMP loss, supporting the role of aromatic ketone triplets in this process. However, for most samples, the incomplete loss of sensitization following borohydride reduction, as well as the inverse dependence of R-TMP on [O-2] for these samples, suggests that there remains another class of oxidizing triplet sensitizer, perhaps quinones.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available