Degradation of nitrogen-heterocyclic compounds by anodic oxidation and electro-Fenton methods.
This study describes the degradation of nitrogen-heterocyclic compounds (NHCs) by anodic oxidation and electro-Fenton. Using indole as a model nitrogen-heterocyclic compound, the removal of indole reached 68% and 97% by anodic oxidation and electro-Fenton, respectively, while the decay of TOC was 15% and 38% correspondingly. By the analysis of ultraviolet-visible spectra and liquid chromatography/mass spectrum, the degradation mechanism of indole by electro-Fenton was proposed as hydroxyl oxidation and anodic oxidation. The degradation of other NHCs including quinoline, isoquinoline and pyridine by anodic oxidation and electro-Fenton revealed the same sequence: quinoline approximately equal isoquinoline > indole >> pyridine. A significant correlation between ln k (natural logarithm of rate constants) and E(LUMO) (the energy of the lowest unoccupied molecular orbit) was obtained by quantitative structure-activity relationship analysis. Degradation of coking plant wastewater showed the removal of COD and TOC were 42% and 22% respectively after 180 min treatment by electro-Fenton.
Songhu
Yuan
Y
Environmental Science Research Institute, Huazhong University of Science and Technology, Wuhan, Hubei, PR China.
Yanchao
Huang
H
Dajun
Ren
R
Xiaohua
Lu
L
D003077:Coke; D004563:Electrochemistry; D004566:Electrodes; D005296:Ferrous Compounds / Q000737:chemistry; D006571:Heterocyclic Compounds / Q000737:chemistry*; D007220:Industrial Waste; D017672:Nitrogen Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D013431:Sulfates / Q000737:chemistry; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D003077:Coke; D005296:Ferrous Compounds; D006571:Heterocyclic Compounds; D007220:Industrial Waste; D017672:Nitrogen Compounds; D013431:Sulfates; D014874:Water Pollutants, Chemical; C012036:sodium sulfate; C020748:ferrous sulfate