Low temperature methanation of syngas in a slurry reactor over Zr-doped Ni/γ-Al₂O₃ catalyst

Zr-doped Ni/γ-Al₂O₃ catalyst was prepared by co-impregnation of Ni and Zr on γ-Al₂O₃; over it, the methanation of syngas at low temperature (300~330 ℃) in a slurry reactor was investigated. Compared with single NiO and Ni/γ-Al₂O₃, the catalytic performance of the Zr-doped Ni/γ-Al₂O₃ is greatly improved. Under optimized condition, a high CO conversion of 86.41% and a selectivity of 90.53% to CH₄ are achieved at a GHSV of 4 200 mL·g^-1·h^-1. XRD, TEM and H₂-TPR results suggest that the doping of Zr promotes dispersion of Ni on γ-Al₂O₃, weakens the interaction between Ni and the support and suppresses the formation of NiAl₂O₄ spinel with low methanation activity; all these may contribute to the excellent performance of the Zr-doped Ni/γ-Al₂O₃ catalyst in syngas methanation.