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

COMELLI NORA A.; RUIZ, MARÍA L.; LEGUIZAMON APARICIO, M. SILVIA; MERINO NORA A.; CECILIA JUAN ANTONIO; RODRIGUEZ CASTELLON, ENRIQUE; LICK, ILEANA D.; PONZI MARTA I

Applied Clays Science

Editorial Board

Lugar: Amsterdam; Año: 2018 p. 148 - 157

0169-1317

In this work, a series of Cu-Mg-Al hydrotalcites and the oxide mixture obtained by their calcination at 600 °Cwere synthesized by coprecipitation from metal nitrates. The effect of the coprecipitation temperature of theprecursor on the structure and texture of these materials was investigated. The solids were characterised byinductively coupled plasma (ICP), atomic absorption spectrophotometry (AAS), an energy dispersive spectrometer(EDAX), thermogravimetric analysis (TGA-DTA), X-ray diffraction (XRD), scanning electron microscopy(SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR). It has beenstudied the activity of these solids as catalysts for diesel soot combustion. The materials are formed by nanoparticles,and the coprecipitation temperature has influence in the morphology of hydrotalcites. Moreover, thecatalytic performance of calcinated solids is influenced by the synthesis conditions. A low temperature coprecipitationis beneficial for the diesel soot combustion. In this sense, the solid obtained by coprecipitacion at 40 °Cshows the best catalytic activity (Tmax=375 °C). This catalyst contains cooper oxides, potassium and nitrate ionswhich can acts as promoters of the soot combustion. The studied solids showed activity and high resistance to thedeactivation caused by hydro-treatment.