Nickel-based Catalyst Precursor Prepared Via Microwave-induced Combustion Method: Thermodynamics of Synthesis and Performance in Dry Reforming of CH4

• Autor(a) principal: Barros,Braulio Silva
• Data de Publicação: 2015
• Outros Autores: Kulesza,Joanna, Melo,Dulce Maria de Araújo, Kienneman,Alain
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Materials research (São Carlos. Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392015000400732
• topic: self-combustion; microwaves; perovskite; amino acids; catalysts

Nickel-based catalyst precursor for dry reforming of methane was successfully prepared by a self-combustion method. Three different amino acids: urea, glycine and citric acid were tested as fuels in the redox reaction with metal nitrates. For each fuel, a thermodynamic modeling of the combustion reaction was performed. The samples were characterized by X-ray diffraction (XRD), Thermogravimetric analysis (TG), Scanning electron microscopy (SEM), Attenuated total reflectance – Fourier transform infrared (ATR-FTIR) spectroscopy and Temperature-programmed reduction (TPR). XRD data confirmed the presence of several crystalline phases in the as-prepared powders. The sample prepared with citric acid showed very low crystallinity when compared to the other samples. It was found that the heat release rate of the self-combustion is the determinant factor of the crystallization, and it is fuel dependent. SEM results suggest that the distribution and average particle size of as-prepared powders can be controlled by the appropriate selection of the fuel. Further calcination of these samples at 800 °C/4h led to the crystallization of perovskite-type structure LaNiO3. Nanostructured Ni0/La2O3 obtained after reduction of LaNiO3 precursor showed high catalytic activity in dry reforming of methane.