Hydrogen Production via
Steam Reforming of Ethanol
on Phyllosilicate-Derived Ni/SiO<sub>2</sub>: Enhanced Metal–Support
Interaction and Catalytic Stability
- Publication date
- Publisher
Abstract
This paper describes the design of Ni/SiO<sub>2</sub> catalysts
obtained from a phyllosilicate precursor that possess high activity
and stability for bioethanol steam reforming to sustainably produce
hydrogen. Sintering of metal particles and carbon deposition are two
major issues of nickel-based catalysts for reforming processes, particularly
at high temperatures; strong metal–support interaction could
be a possible solution. We have successfully synthesized Ni-containing
phyllosilicates by an ammonia evaporation method. Temperature programmed
reduction results indicate that the metal–support interaction
of Ni/SiO<sub>2</sub> catalyst prepared by ammonia evaporation method
(Ni/SiO<sub>2P</sub>) is stronger due to the unique layered structure
compared to that prepared by conventional impregnation (Ni/SiO<sub>2I</sub>). With the phyllosilicate precursor nickel particles highly
disperse on the surface, remaining OH groups in the unreduced phyllosilicates
promote nickel dispersion and carbon elimination. We also show that
high dispersion of Ni and strong metal–support interaction
of Ni/SiO<sub>2P</sub> significantly promote ethanol conversion and
H<sub>2</sub> production in ethanol steam reforming. Ni/SiO<sub>2P</sub> produces less carbon deposition compared to Ni/SiO<sub>2I</sub>;
for the latter, a surface layer of Ni<sub>3</sub>C formed during the
deactivation