An Al₂O₃‑Coated SiC-Supported Ni Catalyst with Enhanced Activity and Improved Stability for Production of Synthetic Natural Gas

An Al₂O₃-coated SiC, Al₂O₃@SiC, was designed via the evaporation-induced self-assembly method to serve as a composite support for Ni catalysts in synthetic natural gas (SNG) production through carbon monoxide (CO) methanation. Scanning electron microscopy images of the Al₂O₃@SiC composite showed that the SiC surface was coated by an Al₂O₃ layer homogeneously. The Ni/Al₂O₃@SiC catalyst exhibited excellent initial activity and superior long-term stability in CO methanation. The structural characterizations revealed that the high activity of the Ni/Al₂O₃@SiC catalyst was mainly due to the small size of Ni nanoparticles and the mesoporous structure of Al₂O₃ layers coated on SiC surface. The superior stability of the Ni/Al₂O₃@SiC catalyst was rationalized by the enhanced anticoke and antisintering properties. The present work will provide guidelines in the synthesis of highly efficient composite catalysts for SNG production.