in slurry-bed reactor are illustrated in Table 3. It is shown that the
conversion of CO of catalyst Ni/Al2O3 was 82.5%, the selectivity of
CH4, C2e4 and CO2 was 87.4%, 7.8% and 4.8%, respectively. The Cepromoted
catalysts exhibited higher conversion of CO and selectivity
of CO2, which increased from 82.5% to 90.5% or above, and
from 4.8% to 10.8% or above, respectively. In addition, the selectivity
of C2-4 decreased from 7.8% to 1.9% or below. The results indicated
that the addition of Ce aggravated the water gas shift reaction
(WGSR, CO þ H2O/CO2 þ H2), which resulted in more production
of CO2. Catalyst NieCe/Al2O3 prepared by coimpregnation of Ni and
Ce exhibited the best catalytic performance, the conversion of CO
and the selectivity of CH4 reached 94.1% and 87.9%, respectively. The
order of the catalytic activity of CO methanation was NieCe/
Al2O3 > Ni/Ce/Al2O3 > Ce/Ni/Al2O3 > Ni/Al2O3.