Hydrophobic SiO2 supported Fe-Ni bimetallic catalyst for the production of high-calorie synthetic natural gas

Abstract Hydrophobic SiO2-supported Fe-Ni bimetallic catalysts were synthesized by facile hydrothermal method, followed by grind-mixing process. The as-synthesized nanoparticles were appointed as robust catalysts in the methanation process to improve the calorific value of the natural gas. Notably, the functionalization of SiO2 surface with a hydrophobic layer was performed using a fluorinated alkyl group, as a critical step to prohibit the water-gas shift (WGS) reaction and consequently produce low amount of CO2 content during the methanation process. The obtained catalytic results demonstrated that Fe1.5Ni1.5 catalyst exhibited an excellent CO conversion of 95.2% at 320 °C with a natural gas calorific value of 56.4 MJ Nm−3, which is much higher than the previously reported results when traditional Ni-based catalysts used. Moreover, the modified hydrophobic catalyst exhibited a lower CO2 selectivity compared with unmodified one. This study provides a new and promising insight for the design and development of high-calorie SNG product.