One-step propylene formation from bio-glycerol over molybdena-based catalysts

Abstract

This work presents a novel, one-step catalytic process, enabling highly selective propylene formation via glycerol hydro-deoxygenation (HDO) reactions. Fe-Mo catalysts, supported on black and activated carbons, are selective towards C-O bond cleavage, thus converting glycerol to propylene with high yields. BET, XRD, TPD-NH 3 and TPD-He methods have been employed for the characterization of the samples. Molybdenum oxide, at its reduced state, is essential for driving selectively the reaction towards complete deoxygenation. The only product of glycerol HDO is propene, in the gas phase, while 2-propenol, propanols and propylene glycol have been detected, among others, in the liquid phase. Under the standard reaction conditions (300°C temperature, 8.0 MPa hydrogen pressure), glycerol conversion exceeds 88% and selectivity to propene reaches 76% after 6 hours of reaction. This study includes the investigation of the operating conditions effect (i.e. reaction time, reaction temperature, catalyst loading and H 2 pressure) regarding glycerol HDO towards propene formation.

Exploring the Reaction Pathways of Bioglycerol Hydrodeoxygenation to Propene over Molybdena‐Based Catalysts

“…MoO 3 was supported on commercially available Black Carbon Vulcan XC72 (Cabot Corporation) following the procedure described previously . The obtained catalyst, with a composition of 20.8 wt % Mo (Mo/BC), was calcined under synthetic air flow at 200 °C for 2 h and then was prereduced at 500 °C for 0.5 h under H 2 flow (reduced samples are indicated as Mo/BC_R).…”

“…Previously,w eh ave provent hat propene can be produced effectively through ao ne-step HDO reactiono fg lycerold erived from biomass,o ver supported Mo and Fe-Mo catalysts;t he study included the synthesis, characterization, and performance evaluation of those catalysts supported on different carbons( black carbon (BC) and activated carbon). [16] Nevertheless, to study and evaluatet he key parameters of selective glycerolc onversion into propene, the simplest catalytic system (Mo/BC) was employed.…”

Vibrational Spectroscopic Characterization of Glycerol Reaction Pathways over Metal‐Modified Molybdenum Carbide Surfaces

“…The reforming reaction breaks the C−H and C−C bonds of glycerol to form syngas (CO+H 2 ) for methanol production and Fisher‐Tropsch synthesis . The complete hydrodeoxygenation (HDO) reaction can cleave all the C−O bonds of glycerol to produce propylene, an industrially important building block . The propylene produced from glycerol can contribute to the on‐purpose production to fill the current gap between propylene market demand and supply .…”

“…[12][13][14][15] The complete hydrodeoxygenation (HDO) reaction can cleave all the CÀ O bonds of glycerol to produce propylene, an industrially important building block. [16][17][18] The propylene produced from glycerol can contribute to the on-purpose production to fill the current gap between propylene market demand and supply. [19] On the other hand, the selective HDO reaction can break one or two CÀ O bonds of glycerol to produce value-added C 3 oxygenates such as acetol, [20,21] propanediol, [22,23] and propanol.…”

Olefins from Biomass Intermediates: A Review

“…In all the above studies, a number of by-products has been detected in the gas phase (e.g., carbon dioxide, propane, and ethylene). Further studies by our group, in a batch reactor, over molybdena-based catalysts supported on carbon, report glycerol production into C 3 H 6 with 100% selectivity in the gas phase (88.0% glycerol conversion and 76.0% selectivity to C 3 H 6 ) at 300 • C and under hydrogen atmosphere (80 bar) (Figure 8) [90]. Our group has also proven that reducible molybdenum oxides selectively drive this reaction into C 3 H 6 , most probably via a reverse Mars-van Krevelen mechanism; formation of Mo 4+ and Mo 5+ species most likely drives the reaction to the formation of the desired product.…”