Characterizations of nanostructured nickel aluminates as catalysts for conversion of glycerol Influence of the preparation methods

ANTONIO NETO; ALCEMIRA OLIVEIRA; JOSUE FILHO; NORMA AMADEO; MARIA L DIEUZEIDE; FRANCISCO SOUSA; ALCINEIA OLIVEIRA

ADVANCED POWDER TECHNOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2017

0921-8831

Three different preparation methods wereapplied to prepare nickel aluminates (i.e. nanocasting(NiAlN), coprecipitation(NiAlC)and wet impregnation(NiAlW) methods). The performances of the catalysts wereevaluated in glycerol dehydration to produce valuable chemical compounds. Allcatalysts exhibited the NiAl2O4 phase besides NiO and g-Al2O3. The NiAlN showed slightly nanoparticlesof the aforesaid oxides whereas NiAlxOy was the predominantphase found over NiAlW catalyst. XRD and Raman measurements of NiAlC suggestthat the particles of NiO or NiAl2O4 oxides are supportedon the mesoporous silica matrix. The sinteringeffects were responsible for the decreased performance of NiAlC in glyceroldehydration. On the contrary, NiAlN is found to be little more active catalystdue to the higher stability of their nanoparticles being the glycerolconversion is 7% at the end of the reaction. Besides, the reaction efficientlyproceeds on NiAlW, which had a high catalytic performance with 24% glycerolconversion to acetol and others products. No   deactivation along of the time was observed inNiAlW catalyst for 25h of time on stream due to the stability of the NiAlxOyphase, which impedes phase transformation and was resistant to  heavy coking.