The degradation of aniline (ArNH2) was facilitated by light irradiation (λ > 370 nm) of an aqueous solution, which contained Fe(III), humic acid (HA), and H{sub}2O{sub}2. The consumption of H{sub}2O{sub}2 and the reduction of Fe(III) to Fe(II) was consistent with the degradation of ArNH{sub}2 via the photo-Fenton reaction, accompanied by the generation of hydroxyl radicals (HO{sup}·). HPLC analysis of the reaction mixture indicated the presence of p-aminophenol, p-hydroquinone, and maleic and fumaric acids and the simultaneous release of (NH{sub}4) {sup}+ ion. However, the sum of the product concentrations, as determined by HPLC after the reaction, was much smaller than the ArNH{sub}2 concentration added initially. This can be attributed to the majority of the ArNH{sub}2 being incorporated into the polymeric structure in the HA after the reaction. The 15{sup left}N NMR and pyrolysis-GC/MS studies indicated that, after the reaction, ArNH{sub}2 formed covalent bonds with quinone and the vinyl carbons in the HA, to form anilino-compounds, such as anilinoquinone and enaminone.
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