Fenton-like degradation enhancement of methylene blue dye with magnetic heating induction

We studied the adsorption/degradation process of methylene blue in a Fenton like process using iron oxide nanoparticles as a source of Fe2+ ions, where the nanoparticles were prepared via a facile electrochemical synthesis method. The degradation kinetics were studied using 2 g L−1 of catalyst and 100 ppm of pollutant at pH 3.5. The influence of temperature on this process was evaluated using two different setups: conventional heating in a thermostatic bath and selective heating using an alternating magnetic field. The magnetic induction heating process led to a greater degradation of the pollutant compared with the thermostatic bath. In addition, the optimal concentration of Fe2+ in solution was evaluated in a Fenton homogeneous process to achieve the same degradation efficiency when using a nanoparticle-assisted Fenton-like process. A concentration of 0.5 ppm Fe2+ in solution yielded the same degradation achieved by using 2 g L−1 of iron oxide nanoparticles. The kinetic analysis fit the pseudo-first-order kinetics and indicated a linear increase in the apparent rate constant with increasing temperature. The activation energy of the degradation process obtained by fitting the Arrhenius equation was 58 kJ mol−1. Fenton like process improved by the synergic use of magnetic nanoparticles and magnetic heating induction. [Display omitted] •Iron oxide nanoparticles are used in a Fenton-like process.•Magnetic induction heating increase degradation of methylene blue•The same amount of Fe2+ in Fenton-like and Fenton are compared.•Fe2+ decrease after degradation of dye has been shown by Mössbauer and XPS spectroscopy.