Photocatalytic degradation of phenanthrene in the presence of akaganeite nano-rods and the identification of degradation products

Abstract

The nano-rods of an iron oxide, akaganeite, were prepared and characterised using X-ray diffraction and field emission scanning electron microscopy. The application of the synthesized nano-rods in the degradation of the polycyclic aromatic hydrocarbon, (phenanthrene) on soil surfaces, was examined. The results reveal the efficient degradation of the pollutant phenanthrene on soil surfaces in the presence of akaganeite nano-rods. The effects of various experimental parameters on the rate of degradation of phenanthrene in the presence of iron oxide were examined. The results indicate that the photodegradation of phenanthrene was fastest under acidic conditions. The rate of photodegradation of phenanthrene increases with the increase in dose of the photocatalyst, akaganeite. The rate of photocatalytic degradation of phenanthrene enhances with the addition of oxalic acid up to the optimum condition due to the occurrence of a Fenton-like mechanism. The intermediate products of phenanthrene formed under acidic, neutral and basic conditions were examined and identified using LC-MS. The results indicated the disappearance of the pollutant phenanthrene after 96 h.