Magnetic nanoreactorsEnvironmental catalysis applications

Resumen

This thesis deals with iron oxide magnetic nanoreactors with catalytic properties for the treatment of polluted waters by taking advantage of their efficient self-heating. This kind of materials presents great advantages such as high surface/volume ratio, reproducibility, selectivity, ability to be magnetic harvested, functionalizable surfaces, high efficiencies and reusability. In particular, this thesis has considered the case of different shaped, coated and structured magnetic iron oxide nanoreactors, which can be easily synthesized at low cost, are biocompatible and present a well-developed surface chemistry. Techniques like thermal decomposition and the polyol method have been analyzed for the synthesis and functionalization of these magnetic nanoparticles. Within the synthesis, the formation mechanism of multicore nanostructures obtained by solvothermal polyol method in an autoclave has been fully understand and compared to microwave-assisted heating. The as-prepared magnetic nanoreactors where used to comprehend the fundamental aspects of adsorption using model inorganic compounds like chromium and lead and model organic molecules like methyl orange, acid orange 8 and methylene blue. Furthermore, tests on the effectiveness of these nanoreactors on the degradation of organic dyes where also analyzed considering the improvement of the reactions when subjecting the material to an alternating magnetic field. Additionally, the industrialization of these processes was explored by scaling up the production of the nanoreactors and using them on the degradation of real systems like leachate from a solid landfill and wastewater from a textile industry. Finally, a proof of concept is presented for the use of the nanoreactors in the removal and degradation of microplastics from daily use cosmetics, demonstrating its versatility.