4. Conclusions
The impregnation sequence of Ni and Ce on g-Al2O3 support had
a great effect on structure and catalytic performance of Ni-based
catalyst for CO hydrogenation to SNG in a slurry-bed reactor.
Catalyst Al2O3 prepared by coimpregnation of Ni and Ce
possessed larger specific surface area, higher dispersion of Ni species,
smaller Ni particle size, lower reduction temperature, and
better catalytic performance than catalyst Ni/Al2O3, Ce/Ni/Al2O3 or
Ni/Ce/Al2O3. Catalyst Al2O3-350 calcined at 350 C reached
maximum catalytic performance, the conversion of CO, the selectivity
of CH4 reached up to around 95.4% and 90.7%, respectively.
With the increase in calcination temperature, the interaction between
Ni species and g-Al2O3 support strengthened, further increase
in calcination temperature decreased the catalyst
reducibility and catalytic performance.