Hydroxyl radical is very reactive, underlying the chemistry of advanced oxidation processes (AOPs) for degrading organic compounds in water. Among various AOPs, Fenton’s reagent has been known to be an effective and simple oxidant. It is found that the Fenton reaction can be an efficiency enhanced in photo-electro-Fenton process since ferric may complex with certain target compounds or byproducts, especially those acting as ligands, produced by UVA light and current. The new design of our system came from the concept of promoting the ferric reduction rate, which can increase the amount of hydroxyl radicals.
In this study investigated photo-electro-Fentonto oxidize 1 mM of 2,6-dimethylaniline and 1.6 mM pyridine. This investigation reveals that photo-electro-Fenton can completely degrade 1 mM of 2,6-dimethylaniline. However only 83.44 % of TOC removal can be eliminated after 240 min of reaction at of 200 mg L-1 of Fe2+, pHi=2, 1800 mg L-1 H2O2, CDc=23.19 A m-2. 94% pyridine degradation and 70% TOC can be removed after 240 min of the reaction in the presence of 50 mg L-1 Fe2+, pHi=2, 1600 mg L-1 H2O2, CDc=4.64 A m-2. In addition, we also calculated the observed reaction constant k1 and k2 with different condition of operation using pseudo-first-order reaction.
Futhermore, the mechanism of 2,6-dimethylaniline and pyridine was proposed in this study. It is also found that 2,6-dimethylaniline can not completely be oxidized to carbon dioxide but transformed to some intermediates which have similar like of 2,6-dimethylaniline and No heterocyclic intermediate in the pyridine system.

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