The chemical background of advanced oxidation processes

Tamás Csay, Renata Homlok, E. Illés, E. Takács, L. Wojnárovits

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

In advanced oxidation processes, the hydroxyl radical is the main initiator of the degradation of pollutants. For aromatic molecules, the rate coefficients are between 2×109 and 1×1010mol-1 dm3 s-1 and show some variation according to the electron-withdrawing or donating nature of the substituents. The one-electron oxidant .OH induces 2-4 electron oxidations of many aromatic pollutants. These high rates are explained by .OH addition to an unsaturated bond, scavenging of the organic radical by dissolved O2, and subsequent reactions. In amino-substituted molecules and in azo dyes the efficiency is lower, because O2 cannot compete efficiently with the unimolecular transformation of carbon-centered radicals. Generally, the toxicity first increases and then decreases with treatment time. The increase is attributed to the high toxicity of some degradation products and to H 2O2 formation. In surface waters, traces of transition metal ions degrade some of the H2O2 in Fenton-like processes.

Original languageEnglish
Pages (from-to)233-241
Number of pages9
JournalIsrael Journal of Chemistry
Volume54
Issue number3
DOIs
Publication statusPublished - 2014

Fingerprint

Oxidation
Toxicity
Electrons
Azo Compounds
Degradation
Molecules
Scavenging
Surface waters
Oxidants
Hydroxyl Radical
Transition metals
Metal ions
Carbon

Keywords

  • adiolysis
  • advanced oxidation processes
  • degradation
  • hydroxyl radical
  • water pollutants

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

The chemical background of advanced oxidation processes. / Csay, Tamás; Homlok, Renata; Illés, E.; Takács, E.; Wojnárovits, L.

In: Israel Journal of Chemistry, Vol. 54, No. 3, 2014, p. 233-241.

Research output: Contribution to journalArticle

@article{837a469961c44a92a347b06f39893ace,
title = "The chemical background of advanced oxidation processes",
abstract = "In advanced oxidation processes, the hydroxyl radical is the main initiator of the degradation of pollutants. For aromatic molecules, the rate coefficients are between 2×109 and 1×1010mol-1 dm3 s-1 and show some variation according to the electron-withdrawing or donating nature of the substituents. The one-electron oxidant .OH induces 2-4 electron oxidations of many aromatic pollutants. These high rates are explained by .OH addition to an unsaturated bond, scavenging of the organic radical by dissolved O2, and subsequent reactions. In amino-substituted molecules and in azo dyes the efficiency is lower, because O2 cannot compete efficiently with the unimolecular transformation of carbon-centered radicals. Generally, the toxicity first increases and then decreases with treatment time. The increase is attributed to the high toxicity of some degradation products and to H 2O2 formation. In surface waters, traces of transition metal ions degrade some of the H2O2 in Fenton-like processes.",
keywords = "adiolysis, advanced oxidation processes, degradation, hydroxyl radical, water pollutants",
author = "Tam{\'a}s Csay and Renata Homlok and E. Ill{\'e}s and E. Tak{\'a}cs and L. Wojn{\'a}rovits",
year = "2014",
doi = "10.1002/ijch.201300077",
language = "English",
volume = "54",
pages = "233--241",
journal = "Israel Journal of Chemistry",
issn = "0021-2148",
publisher = "Wiley-VCH Verlag",
number = "3",

}

TY - JOUR

T1 - The chemical background of advanced oxidation processes

AU - Csay, Tamás

AU - Homlok, Renata

AU - Illés, E.

AU - Takács, E.

AU - Wojnárovits, L.

PY - 2014

Y1 - 2014

N2 - In advanced oxidation processes, the hydroxyl radical is the main initiator of the degradation of pollutants. For aromatic molecules, the rate coefficients are between 2×109 and 1×1010mol-1 dm3 s-1 and show some variation according to the electron-withdrawing or donating nature of the substituents. The one-electron oxidant .OH induces 2-4 electron oxidations of many aromatic pollutants. These high rates are explained by .OH addition to an unsaturated bond, scavenging of the organic radical by dissolved O2, and subsequent reactions. In amino-substituted molecules and in azo dyes the efficiency is lower, because O2 cannot compete efficiently with the unimolecular transformation of carbon-centered radicals. Generally, the toxicity first increases and then decreases with treatment time. The increase is attributed to the high toxicity of some degradation products and to H 2O2 formation. In surface waters, traces of transition metal ions degrade some of the H2O2 in Fenton-like processes.

AB - In advanced oxidation processes, the hydroxyl radical is the main initiator of the degradation of pollutants. For aromatic molecules, the rate coefficients are between 2×109 and 1×1010mol-1 dm3 s-1 and show some variation according to the electron-withdrawing or donating nature of the substituents. The one-electron oxidant .OH induces 2-4 electron oxidations of many aromatic pollutants. These high rates are explained by .OH addition to an unsaturated bond, scavenging of the organic radical by dissolved O2, and subsequent reactions. In amino-substituted molecules and in azo dyes the efficiency is lower, because O2 cannot compete efficiently with the unimolecular transformation of carbon-centered radicals. Generally, the toxicity first increases and then decreases with treatment time. The increase is attributed to the high toxicity of some degradation products and to H 2O2 formation. In surface waters, traces of transition metal ions degrade some of the H2O2 in Fenton-like processes.

KW - adiolysis

KW - advanced oxidation processes

KW - degradation

KW - hydroxyl radical

KW - water pollutants

UR - http://www.scopus.com/inward/record.url?scp=84896549212&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84896549212&partnerID=8YFLogxK

U2 - 10.1002/ijch.201300077

DO - 10.1002/ijch.201300077

M3 - Article

VL - 54

SP - 233

EP - 241

JO - Israel Journal of Chemistry

JF - Israel Journal of Chemistry

SN - 0021-2148

IS - 3

ER -