Abstract
The hydroxyl radical (HO•) is a strong oxidizing agent that can transform dissolved organic matter (DOM) into many intermediate photoproducts and byproducts, which include low molecular weight (LMW) DOM, hydrogen peroxide (H2O2), CO2, dissolved inorganic carbon (DIC: dissolved CO2, H2CO3, HCO3−, and CO32−), NO3−, NH4+, and so on, in surface waters. Furthermore, HO• has a prominent role in the transformation of recalcitrant pollutants into more biodegradable compounds. This chapter discusses the key sources of HO• in natural waters and elucidates the phototransformation pathways of high molecular weight (HMW) and low molecular weight (LMW) DOM induced by HO•. As an example, the photooxidation of methylmercury chloride (MeHgCl) by hydroxyl radicals is discussed along with its reaction mechanism. Among the possible indicators of DOM transformation, the decrease in the fluorescence intensity of autochthonous fulvic acid is discussed based on field observations. The presented results suggest that HO• may be involved in the photooxidation of both HMW and LMW DOM in surface waters.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.