Influence of the synthetic conditions on the composition, morphology of CuMgAl hydrotalcites and their use as catalytic precursor in diesel soot combustion reactions

LICK, ILEANA DANIELA; MERINO, NORA ANDREA; COMELLI, NORA ALEJANDRA; RODRÍGUEZ-CASTELLÓN, ENRIQUE; APARICIO, MARÍA SILVIA LEGUIZAMÓN; PONZI, MARTA ISABEL; CECILIA, JUAN ANTONIO; RUIZ, MARÍA LUCÍA

APPLIED CLAY SCIENCE

ELSEVIER SCIENCE BV

Año: 2018 vol. 157 p. 148 - 157

0169-1317

In this work, a series of Cu-Mg-Al hydrotalcites and the oxide mixtureobtained by their calcination at 600 °C were synthesized by coprecipitationfrom metal nitrates. The effect of the coprecipitation temperature of the precursoron the structure and texture of these materials was investigated. The solidswere characterised by inductively coupled plasma (ICP), atomic absorptionspectrophotometry (AAS), an energy dispersive spectrometer (EDAX), thermogravimetricanalysis (TGA-DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM),X-ray photoelectron spectroscopy (XPS), and Fourier transform infraredspectroscopy (FTIR). It has been studied the activity of these solids ascatalysts for diesel soot combustion. The materials are formed by nanoparticles,and the coprecipitation temperature has influence in the morphology ofhydrotalcites. Moreover, the catalytic performance of calcinated solids is influencedby the synthesis conditions. A low temperature coprecipitation is beneficialfor the diesel soot combustion. In this sense, the solid obtained bycoprecipitacion at 40 °C shows the best catalytic activity (Tmax = 375 °C).This catalyst contains cooper oxides, potassium and nitrate ions which can actsas promoters of the soot combustion. The studied solids showed activity andhigh resistance to the deactivation caused by hydro-treatment.