Reactivity of OH radicals with chlorobenzoic acids-A pulse radiolysis and steady-state radiolysis study

Robert Zona, Sonja Solar, Nikola Getoff, Knud Sehested, Jerzy Holcman

    Research output: Contribution to journalJournal articleResearchpeer-review

    Abstract

    The reactions of OH radicals with 2-, 3-, 4-chlorobenzoic acids (ClBzA) and chlorobenzene (ClBz), k(OH+substrates)=(4.5−6.2)×109 dm3 mol−1 s−1, have been studied by pulse radiolysis in N2O saturated solutions. The absorption maxima of the OH-adducts were in the range of 320−340 nm. Their decay was according to a second-order reaction, 2k=(1−9)×108 dm3 mol−1 s−1. In the presence of N2O/O2 the formation of peroxyl radicals was detectable for 2-, 4-ClBzA and ClBz, k(OH-adduct+O2)=(2−4)×107 dm3 mol−1 s−1, while this reaction for 3-ClBzA was too slow to be registered. In the presence of N2O the degradation rates induced by gamma radiation were very similar for all chlorobenzoic acids, yet the chloride formation was distinctly higher for 3-ClBzA. In the presence of oxygen the initial degradation of 2-and 4-ClBzA equaled the OH-radical concentration, whereas in case of 3-ClBzA only 60% of OH led to degradation. The order for the efficiency of dehalogenation was 4->2->3-ClBzA. Several primary radiolytic products could be detected by HPLC. To evaluate the toxicity of final products a bacterial bioluminescence test was carried out.
    Original languageEnglish
    JournalRadiation Physics and Chemistry
    Volume79
    Issue number5
    Pages (from-to)626-636
    ISSN0969-806X
    DOIs
    Publication statusPublished - 2010

    Fingerprint Dive into the research topics of 'Reactivity of OH radicals with chlorobenzoic acids-A pulse radiolysis and steady-state radiolysis study'. Together they form a unique fingerprint.

    Cite this