Importance of Iron Complexation for Fenton-Mediated Hydroxyl Radical Production at Circumneutral pH
نویسندگان
چکیده
The reaction between Fe(II) and H2O2 to yield hydroxyl radicals (HO ), the Fenton reaction, is of interest due to its role in trace metal and natural organic matter biogeochemistry, its utility in water treatment and its role in oxidative cell degradation and associated human disease. There is significant dispute over whether HO, the most reactive of the so-called reactive oxygen species (ROS), is formed in this reaction, particularly under circumneutral conditions relevant to natural systems. In this work we have studied the oxidation kinetics of Fe(II) complexed by L = citrate, ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) and also measured HO production using phthalhydrazide as a probe compound at pH 8.2. A kinetic model has been developed and utilized to confirm that HO is the sole product of the Fe(II)L-H2O2 reaction for L = EDTA and DTPA. Quantitative HO •
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