In Situ DRIFTS-MS Study of the Anaerobic Oxidation of Ethanol over Spinel Mixed Oxides

The anaerobic oxidation of ethanol over spinel mixed oxides A 2+Fe23+O42- (with A = Co2+, Ni2+, or Fe2+) was studied by means of in situ diffuse reflectance spectroscopy (DRIFTS) and mass spectrometry (MS). The nature of the surface species formed during the reaction and its related gas products were discussed. Different reaction pathways were proposed depending on the catalyst composition. Acetates appeared to be important surface intermediates in the case of the Ni ferrite which is at the same time the most basic and easily reducible catalyst from the set studied, whereas with Co and Fe ferrites, more direct pathways to oxidation products were evidenced but at higher temperatures