Articles producció científica> Enginyeria Química

Synthesis of Chalcone Using LDH/Graphene Nanocatalysts of Different Compositions

  • Identification data

    Identifier: imarina:9230259
    Authors:
    Alvarez, Mayra G.Crivoi, Dana G.Medina, FrancescTichit, Didier
    Abstract:
    Layered double hydroxides (LDH) or their derived mixed oxides present marked acid-base properties useful in catalysis, but they are generally agglomerated, inducing weak accessibility to the active sites. In the search for improving dispersion and accessibility of the active sites and for controlling the hydrophilic/hydrophobic balance in the catalysts, nanocomposite materials appear among the most attractive. In this study, a series of nanocomposites composed of LDH and reduced graphene oxide (rGO), were successfully obtained by direct coprecipitation and investigated as base catalysts for the Claisen–Schmidt condensation reaction between acetophenone and benzaldehyde. After activation, the LDH-rGO nanocomposites exhibited improved catalytic properties compared to bare LDH. Moreover, they reveal great versatility to tune the selectivity through their composition and the nature or the absence of solvent. This is due to the enhanced basicity of the nanocomposites as the LDH content increases which is assigned to the higher dispersion of the nanoplatelets in comparison to bulk LDH. Lewis-type basic sites of higher strength and accessibility are thus created. The nature of the solvent mainly acts through its acidity able to poison the basic sites of the nanocatalysts.
  • Others:

    Author, as appears in the article.: Alvarez, Mayra G.; Crivoi, Dana G.; Medina, Francesc; Tichit, Didier;
    Department: Enginyeria Química
    URV's Author/s: CRIVOI, DANA GEORGIANA / GARCÍA ALVAREZ, MAYRA / Medina Cabello, Francisco
    Keywords: Reduced graphene oxide Nanocomposites Layered double hydroxide Hydrotalcite Claisen–schmidt condensation Base catalysts
    Abstract: Layered double hydroxides (LDH) or their derived mixed oxides present marked acid-base properties useful in catalysis, but they are generally agglomerated, inducing weak accessibility to the active sites. In the search for improving dispersion and accessibility of the active sites and for controlling the hydrophilic/hydrophobic balance in the catalysts, nanocomposite materials appear among the most attractive. In this study, a series of nanocomposites composed of LDH and reduced graphene oxide (rGO), were successfully obtained by direct coprecipitation and investigated as base catalysts for the Claisen–Schmidt condensation reaction between acetophenone and benzaldehyde. After activation, the LDH-rGO nanocomposites exhibited improved catalytic properties compared to bare LDH. Moreover, they reveal great versatility to tune the selectivity through their composition and the nature or the absence of solvent. This is due to the enhanced basicity of the nanocomposites as the LDH content increases which is assigned to the higher dispersion of the nanoplatelets in comparison to bulk LDH. Lewis-type basic sites of higher strength and accessibility are thus created. The nature of the solvent mainly acts through its acidity able to poison the basic sites of the nanocatalysts.
    Thematic Areas: Engineering, chemical Engineering (miscellaneous) Engineering (all) Energy (miscellaneous) Energy (all) Chemical engineering (miscellaneous) Chemical engineering (all)
    licence for use: https://creativecommons.org/licenses/by/3.0/es/
    Author's mail: francesc.medina@urv.cat
    Author identifier: 0000-0002-3111-1542
    Record's date: 2024-06-22
    Papper version: info:eu-repo/semantics/publishedVersion
    Link to the original source: https://www.mdpi.com/2305-7084/3/1/29
    Papper original source: Chemengineering. 3 (1): 29-45
    APA: Alvarez, Mayra G.; Crivoi, Dana G.; Medina, Francesc; Tichit, Didier; (2019). Synthesis of Chalcone Using LDH/Graphene Nanocatalysts of Different Compositions. Chemengineering, 3(1), 29-45. DOI: 10.3390/chemengineering3010029
    Licence document URL: https://repositori.urv.cat/ca/proteccio-de-dades/
    Article's DOI: 10.3390/chemengineering3010029
    Entity: Universitat Rovira i Virgili
    Journal publication year: 2019
    Publication Type: Journal Publications
  • Keywords:

    Chemical Engineering (Miscellaneous),Energy (Miscellaneous),Engineering (Miscellaneous),Engineering, Chemical
    Reduced graphene oxide
    Nanocomposites
    Layered double hydroxide
    Hydrotalcite
    Claisen–schmidt condensation
    Base catalysts
    Engineering, chemical
    Engineering (miscellaneous)
    Engineering (all)
    Energy (miscellaneous)
    Energy (all)
    Chemical engineering (miscellaneous)
    Chemical engineering (all)
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