Chemical and physical behavior of CoFe2O4 in steam-iron process with methanol

In this paper we report on the use of CoFe2O4spinel for the chemical loop processing for hydrogenproduction from methanol as the reducing species. The process is based on two steps: (i) the reductionof the spinel carried out with an organic fuel, with generation of a stream containing CO, CO2, H2O,and H2, followed by (ii) the recovery of the original material oxidation state by means of a re-oxidationwith water, which leads to hydrogen production. Results of characterization carried out by Mössbauerspectroscopy and X-ray diffraction on the material as-synthesized and at different reduction degrees,and results of reactivity experiments during each one of the mentioned steps, are reported and put intoperspective. We found that the complete recovery of the initial oxidation state was indeed not possiblewith only water, and a third step, with the partial re-oxidation of the material with air was needed for acompletion of the cycle.