Abstract:
The carbon deposition and sintering of Ni-based catalysts, used in CO methanation, are the main problems to be solved. In this paper, supported LaNiO
3/Al
2O
3-ZrO
2 catalyst was prepared by neutralization hydrolysis-citric acid complexation method. The effects of La-Ni loading and calcination temperature of support on the structure and catalytic activity of the catalyst were investigated. The structural evolution of catalyst precursor before and after reduction was studied via XRD, H
2-TPR, BET, XPS, TEM and other characterization methods. The results showed that the catalyst supported by homogeneous Al-Zr solid solution was beneficial to form the active component with LaNiO
3 structure, and the Ni
0 derived from LaNiO
3 was the key factor for keeping the activity at high temperature. The La-Ni loading affected the formation of LaNiO
3 and the reduction state of Ni. Among the catalysts studied, 30% of the La-Ni loading was more favorable for the formation of perovskite LaNiO
3. The Ni
0 and La
2O
3 reduced from LaNiO
3 were highly dispersed on the surface of the support, and the Ni
0 nanoparticles were anchored by the support and La
2O
3, which inhibited the migration and aggregation of Ni
0 particles at high temperature and thus led to high thermal stability.