CONICET | Buscador de Institutos y Recursos Humanos

tIn recent years, several works have been addressed to decrease carbon dioxide emission or to capture,to storage and to use it. An attractive option is its use as feedstock of chemical industry, especially indehydrogenation reactions (such as ethylbenzene dehydrogenation to produce styrene), providing anexothermic process which can be operated at lower temperatures, making negligible the cracking prod-ucts. Aiming to find alternative catalysts for this reaction, magnesia-supported iron oxides were studied,being prepared by two different methods. The classical impregnation produced a spinel (MgFe2O4) co-existing with magnesia containing Fe3+species, this catalyst showing higher specific surface area andbeing more active and selective than magnesia. Moreover, the deposition of iron nanoparticles througha magnetic fluid on magnesia produced magnesia-supported hematite nanoparticles co-existing withmagnesia containing Fe3+species. In this case, the specific surface area and the activity were even higherand the solid is much more reducible than the other sample. These findings were associated to hematitenanoparticles and to the lower tendency of iron species to diffuse into magnesia lattice. They show thatthe Fe3+species are more active and selective to styrene as hematite nanoparticles than when they arein the environment of magnesium ferrite.