Influence of UV radiation on the catalytic activity of nanosized cobalt ferrite in the oxidative degradation reaction of dinitrophenol

Abstract

Due to their multi-functionality, spinel ferrites, both doped and undoped, are promising materials for a wide range of practical applications, including catalysis, sustainable production of hydrogen and СО2 deposition, electronic and magnet devices, as well as antibacterial agents. Recently, nanosized ferrites have been actively tested as catalysts in Fenton-like processes of deep oxidative degradation of organic substances in order to purify waste waters of different dyes, phenol and its derivatives, and antibiotics. The goal of this work was to establish the catalytic activity of СоFe2O4 nanopowder synthesised using citrate combustion in the reaction of oxidative degradation of 2,4-dinitrophenol upon the activation of the process with UV radiation. Using citrate combustion, we synthesised the impurity-free nanopowder of CoFe2O4 cobalt ferrite with the average size of particles of about 70 nm and a pronounced agglomeration of particles. The cobalt spinel was tested as a catalyst of Fentonlike reaction of oxidative degradation of 2,4- dinitrophenol with UV radiation of l = 270 nm. This process was differentiated with the sorption of dinitrophenol on a nanosized catalyst. The degree of degradation of 2,4-dinitrophenol in a Fenton-like reaction without the CoFe2O4 catalyst was 14 %, while in the presence of a nanosized catalyst it increased up to 80 %. The effective oxidative degradation of the pollutant was performed in a less acidic environment as compared to a classic Fenton process with a rather large initial concentration of dinitrophenol. This allowed considering the nanosized CoFe2O4 as a promising catalyst of Fenton-like of waste waters purification through deep oxidative degradation of toxins.

Keywords

• catalysis
• nanosized ferrites
• wastewater treatment
• ultraviolet radiation