Síntesis de ferritas de pb, cd y mn vía hidroquímica: Incidencia del anión y el flujo de aire

Resumo

Studies are not known the effects of the salts used in the syntheses on the final stoichiometry of ferrites of type MxFeII (1-x) FeIIIO4 hydrochemical way. To realise the ferrite synthesis of Pb, Cd and Mn in relation Fe2+/M2+ 15:1 being varied conditions of the air flow and using nitrates of Pb, Cd and Mn and chlorides of Cd and Mn, has been the objective of this work. The secured stoichiometries were the same (Pb0.04Fe2.96O4, Cd0.06Fe2.94O4, Mn0.12Fe2.88O4) not finding dependency of the anion to begin with. On ferrites it bases ion nitrate, was a tendency of diminution of Fe2+, with the increase of the air flow. For those of synthesized cadmium and manganese from chloride, a greater diminution of Fe2+ than in the obtained ones from nitrates was observed; probably due to the presence of Cl- that in the middle basic happens to ClO- and these they give rise to the potential oxidation Fe2+ to Fe3+ catalyzed by the own ions participant Fe2+, Fe3+ and Mn2+ in the synthesis. For the cadmium ferrite smaller contents of Fe2+ to the found ones in cadmium ferrites were determined from nitrates; possibly all the Fe2+ by smaller chloride concentration did not oxidize (0.018M) that in the one of manganese (0.036M) and only incidence the catalytic ion effect Fe2+ and Fe3+