Statistical modeling of solution combustion synthesis for Ni/A2O3 catalyst in methane decomposition to hydrogen and carbon nanofibers

This paper is focused on the solution combustion synthesis (SCS) of a set of 90Ni/10Al2O3 2 O 3 (wt. %) catalysts for the production of hydrogen and carbon nanofibers through methane decomposition. A novel approach was employed to optimize the SCS of the catalysts in order to enhance the yields of hydrogen. The obtained catalysts were tested in methane decomposition at 550 degrees C and 1 bar. Transmission electron microscopy, energy-dispersive X-ray spectroscopy, low temperature nitrogen adsorption, and X-ray diffraction were utilized to investigate the catalysts. The SCS process involved programmable heating of a mixture of Ni(NO3)2 & sdot;6H2O 3 ) 2 & sdot; 6H 2 O and Al(NO3)3 & sdot;9H2O 3 ) 3 & sdot; 9H 2 O with citric acid (C6H8O7) 6 H 8 O 7 ) from room temperature to 350-450 degrees C at a heating rates 1-10 degrees C/min and exposure durations of 0-20 min. It was discovered that a high specific yield of hydrogen (17.1 mol/gcat.) cat. ) and carbon nanofibers (171 g/gcat.) cat. ) can be achieved by synthesizing at 450 degrees C using a heating rate of 1 degrees C/min without additional exposure.