Anti-coking Ni encapsulated in SiO2 via one-pot reverse microemulsion method as a versatile catalyst for CO2 methane reforming

This paper reports the varying water-to-surfactant (ω) ratio in reverse microemulsion on the development of Ni encapsulation in bulk SiO2 catalyst for dry reforming of methane. From XRD and TEM analyses, the Ni particle size depends on the water-to-surfactant ratio. It found that an optimized ratio of ω improves the catalytic activity for the dry reforming of methane. The catalyst (Ni-SiO2-ω23) shows 70% CH4 conversion and 78% CO2 conversion at 700 °C and WHSV of 72000 mLgcat−1h−1 operating for 50 h with TOF of 12.6 s−1. It is highly anticipated that the increased fraction of 2:1 nickel phyllosilicate and small Ni particle size contributed to its improved catalytic activity corresponding to the ω ratio. Also, a higher ω value can resist carbon formation in the catalysts, characterized by XRD, TGA, Raman, XPS, and TEM. These results were encouraging that could be applied in similar high-temperature reactions.