Solid base catalysts and combined solid base hydrogenation catalysts for the aldol condensation of branched and linear aldehydes

Hamilton, Christine A.; Jackson, S. David; Kelly, Gordon

doi:10.1016/j.apcata.2003.12.009

Cited by 36 publications

(18 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[10] Excellent yields were achieved upon supporting Pd on the basified silica catalysts (Table 2). NaOH and CaO supported on silica have been reported as active catalystsf or aldol condensation reactions.…”

Section: Resultsmentioning

confidence: 97%

ABE Condensation over Monometallic Catalysts: Catalyst Characterization and Kinetics

Goulas

Günbaş

Dietrich³

et al. 2017

ChemCatChem

View full text Add to dashboard Cite

Herein, we present work on the catalyst development and the kinetics of acetone‐butanol‐ethanol (ABE) condensation. After examining multiple combinations of metal and basic catalysts reported in the literature, Cu supported on calcined hydrotalcites (HT) was found to be the optimal catalyst for the ABE condensation. This catalyst gave a six‐fold increase in reaction rates over previously reported catalysts. Kinetic analysis of the reaction over CuHT and HT revealed that the rate‐determining step is the C−H bond activation of alkoxides that are formed from alcohols on the Cu surface. This step is followed by the addition of the resulting aldehydes to an acetone enolate formed by deprotonation of the acetone over basic sites on the HT surface. The presence of alcohols reduces aldol condensation rates, as a result of the coverage of catalytic sites by alkoxides.

show abstract

Section: Resultsmentioning

confidence: 97%

ABE Condensation over Monometallic Catalysts: Catalyst Characterization and Kinetics

Goulas

Günbaş

Dietrich³

et al. 2017

ChemCatChem

View full text Add to dashboard Cite

show abstract

“…29,208 Using solid base catalysts together with a hydrogenation catalyst, researchers are developing more sustainable systems for condensation-hydrogenation reactions. [209][210][211][212] In these systems, implementation of the Guerbet reaction only implies a preliminary dehydrogenation step, which can easily be integrated for instance in continuous vapor phase reactors. An elegant example is the multistep condensation of ethanol to higher alcohols recently patented by Eastman Chemical Company.…”

Section: Catalysis Science and Technology Minireviewmentioning

confidence: 99%

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

Gabriëls

Hernández

Sels

et al. 2015

Catal. Sci. Technol.

243

233

View full text Add to dashboard Cite

The Guerbet condensation reaction is an alcohol coupling reaction that has been known for more than a century. Because of the increasing availability of bio-based alcohol feedstock, this reaction is of growing importance and interest in terms of value chains of renewable chemical and biofuel production. Due to the specific branching pattern of the alcohol products, the Guerbet reaction has many interesting applications. In comparison to their linear isomers, branched-chain Guerbet alcohols have extremely low melting points and excellent fluidity. This review provides thermodynamic insights and unravels the various mechanistic steps involved. A comprehensive overview of the homogeneous, heterogeneous and combined homogeneous and heterogeneous catalytic systems described in published reports and patents is also given. Technological considerations, challenges and perspectives for the Guerbet chemistry are discussed.

show abstract

“…This process suffers from several shortcomings, including long process flow, high energy consumption, and large emission of alkali wastewater. According to a survey, 30% of the price of 2EHO is used for purification and wastewater treatment 4 . The reaction integration of butanal self‐condensation and 2E2H hydrogenation (that is, one‐step synthesis of 2EHO from butanal) will simplify the process flow and reduce energy consumption.…”

Section: Introductionmentioning

confidence: 99%

NiO‐MnO₂/Nb₂O₅‐TiO₂ catalyzed reaction integration of butanal self‐condensation and successive hydrogenation and its kinetics

Zhang

et al. 2021

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

BACKGROUND The reaction integration of butanal self‐condensation and successive hydrogenation (that is, one‐step synthesis of 2‐ethylhexanol from butanal) is an efficiency way to simply process flow and reduce energy consumption for the commercial manufacture of 2‐ethylhexanol (2EHO). In the present work, a NiO‐MnO2/Nb2O5‐TiO2 catalyst was prepared for the integration reaction to reach a high 2‐ethylhexanol selectivity. Furthermore, the reaction integration was investigated kinetically for the next scale‐up. RESULTS A 2EHO selectivity of 90.0% was achieved at a complete conversion of butanal with the help of reduction‐in‐reaction technique in this reaction integration. The reaction rate of butanal is determined by the reversible aldol self‐condensation reaction and its direct hydrogenation reaction. The reaction order with respect to butanal in the two reactions is, respectively, 2.004 and 1.004. The activation energy of the hydrogenation reaction is higher than that of the forward reaction of the self‐condensation, suggesting the suppressive effect the reaction integration on the direct hydrogenation. CONCLUSION The reaction integration promotes butanal self‐condensation and successive hydrogenation and it suppresses butanal direct hydrogenation by using NiO‐MnO2/Nb2O5‐TiO2 catalyst with the help of reduction‐in‐reaction technique, giving rise to a pretty high selectivity of 2‐ethylhexanol. The establishment of the integration reaction kinetics will lay the foundation for reactor design and analysis. © 2021 Society of Chemical Industry

show abstract

Solid base catalysts and combined solid base hydrogenation catalysts for the aldol condensation of branched and linear aldehydes

Cited by 36 publications

References 9 publications

ABE Condensation over Monometallic Catalysts: Catalyst Characterization and Kinetics

ABE Condensation over Monometallic Catalysts: Catalyst Characterization and Kinetics

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

NiO‐MnO₂/Nb₂O₅‐TiO₂ catalyzed reaction integration of butanal self‐condensation and successive hydrogenation and its kinetics

Contact Info

Product

Resources

About

Solid base catalysts and combined solid base hydrogenation catalysts for the aldol condensation of branched and linear aldehydes

Cited by 36 publications

References 9 publications

ABE Condensation over Monometallic Catalysts: Catalyst Characterization and Kinetics

ABE Condensation over Monometallic Catalysts: Catalyst Characterization and Kinetics

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

NiO‐MnO2/Nb2O5‐TiO2 catalyzed reaction integration of butanal self‐condensation and successive hydrogenation and its kinetics

Contact Info

Product

Resources

About

NiO‐MnO₂/Nb₂O₅‐TiO₂ catalyzed reaction integration of butanal self‐condensation and successive hydrogenation and its kinetics