Thermodynamics conditions for Guerbet ethanol reaction

Review of catalytic systems and thermodynamics for the Guerbet condensation reaction and challenges for biomass valorization

“…Yet, when hydrogen is too strongly adsorbed on the catalyst, transfer of H atoms into the carbon skeleton might become complicated. 101 Many catalytic systems include a transition metal compound to facilitate the (de)hydrogenation steps at lower temperatures. Catalytic systems without transition metals require much higher temperatures for alcohol coupling due to the higher activation energy of dehydrogenation.…”

Influence of Reaction Parameters on the Catalytic Upgrading of an Acetone, Butanol, and Ethanol (ABE) Mixture: Exploring New Routes for Modern Biorefineries

“…Thus, at lower temperatures, the production of shorter chained hydrocarbons is favored and was noted to include such as C 5 or C 6 and ether compounds. Furthermore, subsequent dehydration of the intermediates occur at higher temperatures using the acidic sites of the catalyst, leading to aldol condensation reaction producing the alkene materials found (Olcese and Bettahar, 2013). An increase in the lower carbon number range (C 2 -C 7 ) can be seen when increasing the temperature from 200 to 250 • C, which is then followed by a decrease when testing the reaction at 300 • C. This is again due to the nature of the reaction network that starts with the production of shorter chain hydrocarbons, followed by high temperature aldol condensation, shifting the yield toward C 8 -C 15 .…”

H2 Pressure Dependence in the Homogeneously Catalyzed Guerbet Reaction of Ethanol to Butanol using Mn(I) and Ru(II)

“…[1][2][3] The reaction involves sequential two-fold dehydrogenation, aldol-condensation, and double hydrogenation. [1,2,[13][14][15][16][17] The primary product is 1-butanol, alongside hexanol, 2-ethylbutanol, octanol, 2-ethylhexanol, 3-ethoxybutanol, and traces of C 8 + aromatics. [1,2,16] Besides the use as solvent or building block for plasticizers, [18,19] also an application of the obtained mixture of C 4 + alcohols as a direct source for bio-based fuels with high octane numbers that can for example directly be used in diesel engines is discussed.…”