Bio-syngas methanation towards synthetic natural gas (SNG) over highly active Al2O3-CeO2 supported Ni catalyst

The Al2O3-CeO2 composite supported Ni catalyst was developed for synthetic natural gas (SNG) from bio-syngas methanation. The physico-chemical properties of the Ni-based catalysts were characterized by BET, H2-TPR, XRD, SEM and TG. The methanation tests showed that Ni/Al2O3-CeO2 presented the highest methanation performances at low temperature (91.6% CO conversion with 92% CH4 selectivity at 350 °C) compared with Ni/Al2O3, Ni/ZrO2 and Ni/Al2O3-SiO2, etc. The characterization results indicated that combination of CeO2 with Al2O3 restrained the entering of Ni species into the inside, increasing the Ni species amounts and promoting the dispersion of NiO on the surface of Al2O3-CeO2. In addition, adding CeO2 into Ni/Al2O3 weakened the interaction of NiO-Al2O3 via the strengthening of NiO-CeO2 interaction, promoting the reduction of NiO and formation of active metallic Ni. All of these factors improved the catalytic activity for bio-syngas methanation to SNG and the resistance to carbon deposition for Ni/Al2O3-CeO2.