Superparamagnetic nanoreactors as highly efficient adsorbent for water purification en 10th International Conference on Fine Particle Magnetism (27-30 Mayo 2019)

Abstract

[EN] The present study describes the surface modification of iron oxide magnetic nanoparticles with a double-shell coating of silica to obtain mesoporous superparamagnetic nanocomposites with high surface area, identified as nanoreactors (NRs), capable of providing a confined space for organic and inorganic pollutants removal. Adsorption tests were carried out for Lead (Pb2+) and methyl orange (MO) and the effects of different parameters such as pH, pollutant initial concentration, and contact time were analysed. The pseudo second-order model best described the adsorption kinetics for all NRs in the adsorption process of both, organic and inorganic pollutants. Intraparticle diffusion was also found to be involved in the MO adsorption, but is not the limiting stage. The adsorption isotherms were best described by the Langmuir model, suggesting that the adsorption takes place in monolayer. The maximum adsorption capacity value increases from 35 up to 50 mg/gNR with the increasing surface area for Pb2+ removal, while for MO it goes up to 240 mg/gNR. The NRs have excellent cyclability for MO sorption/desorption by simple acid treatment, recovering 100%during the first 4 cycles.