Steam reforming of clean biogas over Rh and Ru open-cell metallic foam structured catalysts

The valorisation of clean biogas (CH4/CO2 = 60/40 v/v) by steam reforming over metal open-cell foam-based structured catalysts was investigated. NiCrAl foams were coated by RuMgAl or RhMgAl hydrotalcite-type compounds through electrodeposition to obtain, after calcination, a thin and stable catalytic film of oxides. The active sites for the reforming reactions are highly dispersed Rh or Ru nanoparticles stabilized by a strong metal support interaction, large Ni particles segregated from the support during reduction and reaction, and Rh/Ni bimetallic particles formed by the interaction of the two formers. Rh-based catalysts show superior activity and stability with the time on stream than Ru catalysts, and a low carbon deposition, which is mainly ascribable to the presence of large Ni particles. In comparison to a pelletized catalyst, the structured catalysts are allowed to operate at high space velocities and low Steam to CH4 ratio, increasing the biogas valorisation and thus the productivity.

Automated summary

The valorisation of clean biogas by steam reforming over metal open-cell foam-based structured catalysts was studied, showing that Rh-based catalysts exhibit superior activity and stability compared to Ru catalysts, leading to reduced carbon deposition and increased biogas valorisation and productivity.