Iron hydroxyl radical, hydrogen peroxide determination

Iron(II) hydroxyl radical, hydrogen peroxide determination, 641... 

Rate constants have been determined for the reduction of hydrogen peroxide by iron(II) and a number of iron(II) complexes. These rate constants have been compiled in Table 2. It is immediately clear that there is not much agreement between the results of various groups. However, there is a discernable trend metal complexes with more water-accessible coordination sites react faster. Graf et al. [117] have commented upon the importance of coordinated water molecules for the Fenton reaction. It is also clear that the rate of the Fenton reaction for a chelated complex near neutral pH is much faster than that of aqueous iron(II) at low pH. The use of the low-pH value of 16M ] s l in a recent calculation [118] of the flux of hydroxyl radicals in a cell gives an estimate that is at least two orders of magnitude too low. 

Catalytic activity of composites B-N-Fe and Si-N-Fe when applying UV radiation in presence of hydrogen peroxide, oxalic acid, and EDTA is determined by formation of photo-Fenton, ferric-oxalate, and Fe-EDTA systems in the solution which leads to generation of the super-oxidant-hydroxyl radicals. At the same time, solutions practically are not polluted by iron. High catalytic activity of the composites is determined by combination of heterogeneous and homogeneous catalyses. 

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