Energy & Fuels, Vol.17, No.1, 13-17, 2003
Catalytically activated metal foam absorber for light-to-chemical energy conversion via solar reforming of methane
CO2 reforming of methane was examined under direct irradiation of the catalytically activated metal foam absorber by solar-simulated, concentrated visible light in the small receiver-reactor system with a transparent window. Rh, Ru, or Ni was applied as the active metal on the aluminacoated or noncoated Ni-Cr-Al metal foam disk for the preparation of the absorber. Rh showed the best activity on the noncoated metal foam while Ru was the best on the alumina-coated one. The most active and stable RU Al2O3/Ni-Cr-Al-foam absorber yielded a maximum methane conversion of 73% at a GHSV of 8500 h(-1) and at ambient pressure, in which about 50% of the incident light energy reaching the absorber was stored as chemical enthalpy at a relatively low value of the average input-power density of radiation, rho = 180 kW m(-2) (the peak flux density of 274 kW m-2 at the center of the irradiated surface of the absorber). This catalytically activate metal foam absorber will be used in the receiver-reactor system for solar methane reforming at relatively low-energy fluxes of concentrated solar radiation.