Hydrosol : Advanced monolithic reactors for hydrogen generation from solar water splitting

Abstract

The HYDROSOL research team has developed an innovative solar thermo-chemical reactor for the production of hydrogen from water splitting, constructed from special refractory ceramic thin-wall, multi-channeled (honeycomb) monoliths that absorb solar radiation. The monolith channels are coated with active water-splitting materials capable to split water vapor passing through the reactor by ‘trapping’ its oxygen and leaving in the effluent gas stream as product pure hydrogen. In a next step, the oxygen ‘trapping’ material is solar-aided regenerated (i.e. releases the oxygen absorbed) and hence a cyclic operation is established. The first kind of such a pilot-scale reactor was designed, built and is currently operating in a continuous mode at a solar furnace facility, producing hydrogen by cyclic operation exclusively at the expense of solar energy; up to 40 cycles of constant H2 production were operated in a row in a two-day continuous production of hydrogen. Further scale-up of the technology and its effective coupling with solar concentration systems are in progress to demonstrate large-scale feasibility of a ‘solar hydrogen’ production plant. Such plants can offer new opportunities to regions of the world that have a huge ‘solar potential’ like countries of Maghreb, that can become important local producers of ‘clean hydrogen’.