Formic acid (FA) is a by-product of some “second generation” biorefineries, which transform non-food biomass to fuel additives [1]. Catalytic vapor phase transfer hydrogenation of olefins (ethylene and propylene) by FA (1) and hydrogen production from FA (2) have been studied.
HCOOH + C2H4 -> CO2 + C2H6 (1)
HCOOH -> H2 + CO2 (2)
A very small amount of a 10 wt.% Pd/C catalyst (6.8 mg) with the mean Pd particles size of 5.4 nm (Fig. 1) catalyzed decomposition of FA and hydrogenation of ethylene by FA at temperatures as low as 358-433 K. In hydrogenation, up to 95% of hydrogen from FA was consumed by ethylene with ethane formation. CO formation was negligible. Higher conversion of FA was observed in the presence of ethylene. Water vapor had a positive effect, but hydrogen - negative. The mechanism of hydrogenation by FA could involve the formation of adsorbed hydrogen from FA and its consumption by the olefin. That the second step is probably fast was indicated by the observation that the olefins examined could both be hydrogenated by H2 over the Pd/C catalyst with 100% conversion even at 313 K. As compared to the Pd catalyst, Au/C and Au/TiO2 catalysts were found to be less active in FA decomposition; neither hydrogenated the olefins.
Hence, FA hydrogenated ethylene and propylene over the Pd/C catalyst effectively, thus eliminating the need for a separate step of H2 production. This approach may have applications in hydrogenation and hydrodeoxygenation reactions of some biomass derived chemicals necessary for the production of fuel additives.
[1] Hayes, D. J.; Fitzpatrick, S.; Hayes, M. H. B.; Ross, J. R. H., In Biorefineries-Industrial Processes and Products, Kamm, B.; Gruber, P. R.; Kamm, M., Eds. Wiley-VCH: Weinheim, 1 (2006), 139-164.
A catalysis expert and member of the Charles Parsons Initiative. Is examining producing hydrogen and bio-oil from biomass and the catalytic conversion of biorefining products.
A leading figure in the field of catalysis. Is looking at the production of hydrogen from biomass and mechanisms for the downstream-conversion of the products of biorefining.
Recent News Articles
Oct 3, 2009
Project Update:Formic Acid for Hydrogenation
The webpage detailing our work on the use of formic acid, which can be a by-product of some biorefining schemes (such as the one being developed in DIBANET), as a hydrogen donor has been updated. Dmitri Bulushev is the person with most involvement in this project. More details can be found on the appropraite webpage.
