Dehydrogenation of alcohol on hydride-forming rare-earth intermetallic compounds (RFe2 and R2Co7)

Abstract

The vapour-phase dehydrogenation of methanol, ethanol and propan-2-ol has been studied over hydride-forming rare-earth intermetallic compounds (ErFe₂, DyFe₂, Nd₂Co₇ and Sm₂Co₇). Under mild conditions methanol, ethanol and propan-2-ol were selectively dehydrogenated to carbon monoxide, acetaldehyde and acetone, respectively, forming metal hydrides simultaneously. The dehydrogenation in the presence of these hydride-forming compounds is recognized as a useful dehydrogenative method, in which R₂Co₇ and RFe₂ are amenable to conversion into stable metal hydrides. The dissociative chemisorption of alcohol on the activated alloy surfaces with subsequent migration of the liberated H to the underlying alloy phase is expected. The dehydrogenation of methanol and ethanol is by a rate-limited dissociation reaction. The behaviour of the reaction has also been characterized by isotope techniques.