Influences of precipitate rinsing solvents on Ni catalyst for methane decomposition to CO(x)-free hydrogen.

Influences of precipitate rinsing solvents on Ni for methane decomposition to CO(x)-free hydrogen has been investigated in this study. Calcination of nickel hydroxide precipitates rinsed by ethanol leads to the formation of nanosheet needle-like NiO, whereas calcination of those rinsed by deionized water leads to the formation of pure nanosheet NiO. When compared to Ni catalyst (Ni-et) reduced from nanosheet needle-like NiO, Ni catalyst (Ni-etwt), reduced from pure nanosheet-like NiO, exhibits a better catalytic performance for methane decomposition. Among the different rinsing processes, nickel hydroxide precipitates, rinsed first by ethanol and subsequently by deionized water, were calcined to the most suitable nanosheet NiO, which could be reduced to Ni-etwt catalyst with the highest catalytic performance of methane decomposition. A total of 1954 mol(H2)/mol(Ni) of hydrogen yields could be obtained over Ni-etwt under suitable reaction conditions. Characterization results indicate that Ni-etwt with the higher catalytic activity has the approximately 34 nm of average particle size.