Acetic Acid Reduction to Acetaldehyde over Iron Catalysts

Rachmady, W.; Vannice, M. A.

doi:10.1006/jcat.2002.3560

Cited by 25 publications

(24 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[32,35,36] Kinetic studies by Rachmady and Vannice supported this mechanism as they demonstrated the reaction fits a Langmuir-Hinshelwood model for two reactants binding at two different types of site. [30,37] XRD analysis of our catalyst showed only metallic iron, and gave no evidence of the oxide (Fig. 1d).…”

Section: Mechanism Of Oleic Acid Hydrotreatment With Fe-msnmentioning

confidence: 87%

Supported iron nanoparticles for the hydrodeoxygenation of microalgal oil to green diesel

Kandel

Anderegg

Nelson

et al. 2014

Journal of Catalysis

140

View full text Add to dashboard Cite

Iron nanoparticles supported on mesoporous silica nanoparticles (Fe-MSN) catalyze the hydrotreatment of fatty acids with high selectivity for hydrodeoxygenation over decarbonylation and hydrocracking. The catalysis is likely to involve a reverse Mars-Van Krevelen mechanism, in which the surface of iron is partially oxidized by the carboxylic groups of the substrate during the reaction. The strength of the metal-oxygen bonds that are formed affects the residence time of the reactants facilitating the successive conversion of carboxyl first into carbonyl and then into alcohol intermediates, thus dictating the selectivity of the process. The selectivity is also affected by the pretreatment of Fe-MSN, the more reduced the catalyst the higher the yield of hydrodeoxygenation product. Fe-MSN catalyzes the conversion of crude microalgal oil into dieselrange hydrocarbons. Disciplines Materials Chemistry | Other Chemistry | Physical ChemistryComments NOTICE: this is the author's version of a work that was accepted for publication in Journal of Catalysis. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Catalysis, [314, (2014)

show abstract

Section: Mechanism Of Oleic Acid Hydrotreatment With Fe-msnmentioning

confidence: 87%

Supported iron nanoparticles for the hydrodeoxygenation of microalgal oil to green diesel

Kandel

Anderegg

Nelson

et al. 2014

Journal of Catalysis

140

View full text Add to dashboard Cite

show abstract

“…[54] The BET surface area, pore volume, and pore diameter of the fresh catalyst samples were determined by N 2 physisorption. Fe dispersion on alumina was determined by CO chemisorption in aM icromeritics ASAP 2020 instrument.…”

Section: Characterisationo Ff Resh Catalystsmentioning

confidence: 99%

The Effect of Copper Loading on Iron Carbide Formation and Surface Species in Iron‐Based Fischer–Tropsch Synthesis Catalysts

et al. 2018

View full text Add to dashboard Cite

The effect of copper as promoter on iron carbide formation and the nature of surface species on iron‐based catalyst during Fischer–Tropsch synthesis (FTS) was investigated. Iron‐based catalysts (15 wt % of Fe) supported on alumina promoted with copper (0, 0.6, 2, and 5 wt %) were characterised in situ at relevant FTS conditions. The catalysts promoted with 2 and 5 wt % of Cu showed higher catalytic activity due to the formation of Hägg carbide (Fe5C2) detected by in situ XANES and XRD. The carbide formation is attributed to a weakening of the iron–alumina mixed‐compound interactions, and hence increasing iron reducibility and dispersion. The in situ XANES measurements indicated a maximum carburization degree (ca. 20–22 %) even at high Cu loading. The catalyst promoted with 5 wt % of Cu exhibited higher water‐gas shift activity. Aliphatic hydrocarbons, formate, and carboxylate species were detected on the catalyst surface during FTS. After exposing the spent catalysts to hydrogenation conditions, the carboxylate species remained strongly adsorbed while aliphatic hydrocarbons and formate species disappeared. The accumulation of oxygenates species on the catalyst surface increased with Cu loading. The interaction of oxygenates with alumina and iron oxide particles (FexOy) were revealed, with the latter being a possible reason for inhibition of further iron carburization.

show abstract

“…For many reducible oxides, surface ketonization could be almost completely suppressed with the addition of noble metals (e. g., Pt, Pd), which also led to marked enhancements in hydrogenation rates compared to the oxide alone. Iron oxides (Fe 3 O 4 , Fe 2 O 3 ), supported or unsupported, have been shown to catalyze acetic acid HDO at significantly higher temperatures than those (<500 K) for noble metal catalysts, yet selectively forming acetaldehyde (∼90 % at <12 % conversion; ∼80 % at 40 % conversion); the aldehyde selectivity further increased with the H 2 pressure. The reductive pretreatment (in H 2 ) temperature of iron oxides was also found to affect their catalytic performance .…”

Section: Hydrogenolysis and Hydrogenation Of Small Mono‐oxygenatesmentioning

confidence: 99%

Valorization of Biomass‐derived Small Oxygenates: Kinetics, Mechanisms and Site Requirements of H₂‐involved Hydrogenation and Deoxygenation Pathways over Heterogeneous Catalysts

Shi

2019

ChemCatChem

View full text Add to dashboard Cite

Hydrodeoxygenation (HDO) is a key step in upgrading of biomass‐derived feedstocks to fuels and valuable chemicals. In this review, I select to discuss the current understanding of heterogeneous HDO catalysis of representative small oxygenates that are present in the bio‐crude obtained from thermochemical conversions of biomass raw materials, as the efficient valorization of these presently underutilized carbon sources would significantly improve carbon recovery and the overall process techno‐economics, in addition to facilitating downstream processing in some cases. A primary focus is laid on the kinetics, mechanisms and active site requirements of molecular H2‐involved hydrogenation and deoxygenation reactions of small aliphatic oxygenates. More often than not, surprising contrasts are found between gas‐solid and polar liquid‐solid interfaces and hint toward substantial restructuring and modifications of the catalytic surfaces and chemistries in polar liquids, particularly induced by protic molecules (the most abundant being water). Knowledge gaps, uncharted territories and associated challenges for the interrogations of these fundamental aspects are also discussed in this review.

show abstract

Acetic Acid Reduction to Acetaldehyde over Iron Catalysts

Cited by 25 publications

References 42 publications

Supported iron nanoparticles for the hydrodeoxygenation of microalgal oil to green diesel

Supported iron nanoparticles for the hydrodeoxygenation of microalgal oil to green diesel

The Effect of Copper Loading on Iron Carbide Formation and Surface Species in Iron‐Based Fischer–Tropsch Synthesis Catalysts

Valorization of Biomass‐derived Small Oxygenates: Kinetics, Mechanisms and Site Requirements of H₂‐involved Hydrogenation and Deoxygenation Pathways over Heterogeneous Catalysts

Contact Info

Product

Resources

About

Acetic Acid Reduction to Acetaldehyde over Iron Catalysts

Cited by 25 publications

References 42 publications

Supported iron nanoparticles for the hydrodeoxygenation of microalgal oil to green diesel

Supported iron nanoparticles for the hydrodeoxygenation of microalgal oil to green diesel

The Effect of Copper Loading on Iron Carbide Formation and Surface Species in Iron‐Based Fischer–Tropsch Synthesis Catalysts

Valorization of Biomass‐derived Small Oxygenates: Kinetics, Mechanisms and Site Requirements of H2‐involved Hydrogenation and Deoxygenation Pathways over Heterogeneous Catalysts

Contact Info

Product

Resources

About

Valorization of Biomass‐derived Small Oxygenates: Kinetics, Mechanisms and Site Requirements of H₂‐involved Hydrogenation and Deoxygenation Pathways over Heterogeneous Catalysts