Investigation of Humic Substance Photosensitized Reactions via Carbon and Hydrogen Isotope Fractionation

Logo poskytovatele

Varování

Publikace nespadá pod Fakultu sportovních studií, ale pod Přírodovědeckou fakultu. Oficiální stránka publikace je na webu muni.cz.
Autoři

ZHANG Ning SCHINDELKA Janine HERRMANN Hartmut GEORGE Christian ROSELL Monica HERRERO-MARTIN Sara KLÁN Petr RICHNOW Hans-Hermann

Rok publikování 2015
Druh Článek v odborném periodiku
Časopis / Zdroj Environmental Science and Technology
Fakulta / Pracoviště MU

Přírodovědecká fakulta

Citace
www http://pubs.acs.org/doi/abs/10.1021/es502791f
Doi http://dx.doi.org/10.1021/es502791f
Obor Organická chemie
Klíčová slova photochemistry; isotopes; photosensitization; humic substrances
Popis Humic substances (HS) acting as photosensitizers can generate a variety of reactive species, such as OH radicals and excited triplet states ((HS)-H-3*), promoting the degradation of organic compounds. Here, we apply compound-specific stable isotope analysis (CSIA) to characterize photosensitized mechanisms employing fuel oxygenates, such as methyl tert-butyl ether (MTBE) and ethyl tert-butyl ether (ETBE), as probes. In oxygenated aqueous media, Delta (Delta delta H-2/Delta delta C-13) values of 23 +/- 3 and 21 +/- 3 for ETBE obtained by photosensitization by Pahokee Peat Humic Acid (PPHA) and Suwannee River Fulvic Acid (SRFA), respectively, were in the range typical for H-abstraction by OH radicals generated by photolysis of H2O2 (Delta = 24 +/- 2). However, (3)HS* may become a predominant reactive species upon the quenching of OH radicals (Delta = 14 +/- 1), and this process can also play a key role in the degradation of ETBE by PPHA photosensitization in deoxygenated media (Delta = 11 +/- 1). This is in agreement with a model photosensitization by rose bengal (RB2-) in deoxygenated aqueous solutions resulting in one-electron oxidation of ETBE (Delta = 14 +/- 1). Our results demonstrate that the use of CSIA could open new avenues for the assessment of photosensitization pathways.
Související projekty:

Používáte starou verzi internetového prohlížeče. Doporučujeme aktualizovat Váš prohlížeč na nejnovější verzi.

Další info