Ultrasound and UV assisted Fenton treatment of recalcitrant wastewaters using transition metal-substituted-magnetite nanoparticles

Ultrasound and UV assisted Fenton treatment of recalcitrant wastewaters using transition metal-substituted-magnetite nanoparticles

Type	Journal Article
Author	Shima Rahim Pouran
Author	Abolfazl Bayrami
URL	http://www.sciencedirect.com/science/article/pii/S0167732216313873
Volume	222
Pages	1076-1084
Publication	Journal of Molecular Liquids
Date	October 2016
Abstract	The degradation and mineralization of two dyes were examined through heterogeneous Fenton using modified magnetite nanoparticles. Researchers prepared the Nb and Mo substituted magnetite samples by co-precipitation method and characterized by BET, XRD, TEM, XPS, VSM and chemical experiments. Their primary emphasis was on the examination of the effects of external energy sources on the activity of the Fe2.79Mo0.13O4, Fe2.79Nb0.19O4 and Fe2.79Nb0.171Mo0.023O4 nanoparticles in Fenton reaction. They employed methylene blue (MB) and methyl orange (MO) as the model cationic and anionic dyes. All samples exhibited exceptional activities in Fenton reaction under the influence of UV and ultrasound (US) energy compared to unmodified magnetite sample. The incorporated Nb and Mo significantly accelerated the MB degradation in US/Fenton followed by UV-B/Fenton and UV-A/Fenton reactions. However, the UV-B/Fenton was more effective in degradation of MO compared to other oxidation systems. Under all the studied conditions, co-doped Nb-Mo-magnetite nanoparticles showed highest activity in comparison to single Nb- and Mo-substituted magnetite samples. MB degradation through both UV and US/Fenton reactions were well described by pseudo-first-order equations in kinetics. The employed catalysts showed acceptable stability under the influence of UV and US irradiations. Although, the amount of leached Nb was relatively higher than Fe and Mo in acidic condition and under UV irradiation, the loss in the performance of the samples was insignificant. Results indicated that it is possible to treat wastewaters effectively by developing nano-catalysts with slight modification in naturally available compounds and using the existing advanced oxidation system.