ESTUDIO DE LA FAMILIA DE PEROVSKITAS DOBLES La2MMnO6 EN LA COMBUSTIÓN CATALÍTICA DE PROPANO DILUIDO

JULIA E. TASCA; ARACELI E. LAVAT; MARÍA GLORIA GONZÁLEZ

Concepción

Congreso; 15º Congreso Internacional de Metalurgia y Materiales; 2015

SAM/CONAMET, Universidad de Concepción

The synthesis, structural, spectroscopic and morphological characterization; and the evaluation of the catalytic properties, of a family of oxides La2MMnO6, with M=Co, Ni y Cu is presented in this work. The materials were obtained by solid state reaction (FS) and through citrate route (CIT). The structure was determined by X-ray diffraction (DRX) and a correlation between the crystal cell parameters and the M(II) cation sizes, as a consequence of MO6 and MnO6 octahedral ordering, was found. The sizes of the particles, estimated by Scherrer equation, are in nanometric scale and hence specific areas are significant. During the spectroscospic characterization of the materials, obtained by CIT route, carried out by FTIR, it was observed a diminution of the bond strength M2+-O-Mn4 according with M(II) sizes, in the sequence: Cu>Ni>Co; and hence the most labile O species should be present in La2CoMnO6-CIT. The SEM morphology of this oxide confirmed the presence of agglomerated tiny particles, in accordance with X-ray diffraction results. The catalytic tests, using propane as reaction test, were carried out in a fixed bed micro reactor, coupled with an ?on line? chromatograph. Despite M(II) cations the materials, obtained by CIT route, are better suited for the reaction and the catalyst La2CoMnO6-CIT is the most active of the investigated series for propane combustion with T90~500ºC.