Abstract:
Syngas production from CH4 is the most economical route for CH4 effective
utilization. Partial oxidation of methane (POM) is one of the best methane activation
process for syngas production. Catalytic materials employed in POM requires a better
catalytic performance in terms of activity and stability to make this process
commercially applicable. Hydrotalcites, owing to their strong basic properties and
uniform distribution of metallic particles inside their structure are suitable for POM
applications. CeO2 with strong redox properties due to its high oxygen storage capacity
is an effective promoter for POM reaction.
In this work, partial oxidation of methane (POM) was investigated using Mg-Ni-Al
(MNA) hydrotalcite promoted CeO2 catalyst in a fixed bed reactor. MNA hydrotalcite
was synthesized using the co-precipitation process, while CeO2 was incorporated via
the wetness impregnation technique. The CeO2@MNA samples were characterized by
X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive Xray
analysis
(EDS),
thermal
gravimetric analysis (TGA), Fourier transform infrared
spectroscopy (FTIR), and Brunauer-Emmett-Teller (BET) technique. The catalytic
activity of CeO2 promoted MNA (CeO2@MNA) for POM reaction was evaluated for
various CeO2 loading kept the feed ratio CH4/O2=2 at 850 °C. The catalyst containing
10 wt.% cerium loading (10%CeO2@MNA) showed 94% CH4 conversion with H2/CO
ratio above 2.0, that is more suitable for FT synthesis. The performance of catalyst is
attributed to highly crystalline stable CeO2@MNA with better Ce-MNA interactions
withstand for 35 h time on stream. Furthermore, the spent catalyst was examined by
TGA, SEM-EDS, and XRD to evaluate the carbon formation and structural changes
during the span of reaction time.
