Characterizing Hydroxyl Radical Formation from the Light-Driven Fe(II)-Peracetic Acid Reaction, a Key Process for Aerosol-Cloud Chemistry

The reaction of peracetic acid (PAA) and Fe(II) has recently gained attention due to its utility in wastewater treatment and its role in cloud chemistry. Aerosol-cloud interactions, partly mediated by aqueous hydroxyl radical (OH) chemistry, represent one of the largest uncertainties in the climate system. Ambiguities remain regarding the sources of OH in the cloud droplets. Our research group recently proposed that the dark and light-driven reaction of Fe(II) with peracids may be a key contributor to OH formation, producing a large burst of OH when aerosol particles take up water as they grow to become cloud droplets, in which reactants are consumed within 2 min. In this work, we quantify the OH production from the reaction of Fe(II) and PAA across a range of physical and chemical conditions. We show a strong dependence of OH formation on ultraviolet (UV) wavelength, with maximum OH formation at λ = 304 ± 5 nm, and demonstrate that the OH burst phenomenon is unique to Fe(II) and peracids. Using kinetics modeling and density functional theory calculations, we suggest the reaction proceeds through the formation of an [Fe(II)-(PAA)2(H2O)2] complex, followed by the formation of a Fe(IV) complex, which can also be photoactivated to produce additional OH. Determining the characteristics of OH production from this reaction advances our knowledge of the sources of OH in cloudwater and provides a framework to optimize this reaction for OH output for wastewater treatment purposes.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - year:2024

Enthalten in:

Environmental science & technology - (2024) vom: 15. Apr.

Sprache:

Englisch

Beteiligte Personen:

Campbell, Steven J [VerfasserIn]
La, Chris [VerfasserIn]
Zhou, Qingyang [VerfasserIn]
Le, Jason [VerfasserIn]
Galvez-Reyes, Jennyfer [VerfasserIn]
Banach, Catherine [VerfasserIn]
Houk, K N [VerfasserIn]
Chen, Jie Rou [VerfasserIn]
Paulson, Suzanne E [VerfasserIn]

Links:

Volltext

Themen:

Fe(IV)
Fenton chemistry
Iron photochemistry
Journal Article
Kinetics model
PH dependence
Peroxy acids

Anmerkungen:

Date Revised 15.04.2024

published: Print-Electronic

Citation Status Publisher

doi:

10.1021/acs.est.3c10684

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM371091489