Defective UiO-66(Zr) as an efficient catalyst for the synthesis of bio jet-fuel precursors via aldol condensation of furfural and MIBK

The production of jet-fuel precursors from furfural (FUR) via aldol-condensation with methyl-isobutyl ketone (MIBK) over a defective UiO-66(Zr) catalyst is presented. The resultant C11 adduct (FuMe) would allow the selective production of branched alkanes in the range of jet fuel via a subsequent hy...

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Detalles Bibliográficos
Autores: Flor, Daniel de la, López-Aguado, Clara, Paniagua, Marta, Morales, Gabriel, Mariscal López, Rafael, Melero, Juan Antonio
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2021
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/377472
Acceso en línea:http://hdl.handle.net/10261/377472
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85111056330&doi=10.1016%2fj.jcat.2021.07.006&partnerID=40&md5=1a2d841df5c501423d757e408fffb8eb
Access Level:acceso abierto
Palabra clave:Aldol condensation
Bio-jet fuel
Furfural
Lignocellulose
MOF
UiO-66
Zirconium
Descripción
Sumario:The production of jet-fuel precursors from furfural (FUR) via aldol-condensation with methyl-isobutyl ketone (MIBK) over a defective UiO-66(Zr) catalyst is presented. The resultant C11 adduct (FuMe) would allow the selective production of branched alkanes in the range of jet fuel via a subsequent hydrogenation/hydrodeoxygenation process. The catalyst is prepared using formic acid as modulator, leading to the incorporation of defects on the microcrystalline structure of the metalorganic framework (MOF) material, which dramatically boosts the catalytic performance in this transformation. Thus, the benchmarking with different commercial solid acid catalysts and Zr-based heterogeneous catalysts has identified the defective MOF, UiO-66(Zr)-FA, as clearly superior. An extensive characterization of the modified catalyst by means of X-ray diffraction (XRD), argon adsorption isotherm, thermogravimetry (TGA), acid titration, X-ray photoelectron spectroscopy (XPS), and diffuse reflectance infrared Fourier transform (DRIFT) of adsorbed deuterated acetonitrile, has confirmed the incorporation of missing-linker and missing-node defects within the structure, enabling to explain the enhancement in the catalytic process. The analysis of the reaction kinetics, together with the optimization of the reaction conditions by means of a response surface methodology (allowing predicting the behaviour of the catalytic system under very different conditions) have identified the temperature as the most relevant parameter affecting the selectivity to FuMe. Thus, under the optimized reaction conditions (130 °C; 4 h; FUR/Cat = 2; MIBK/FUR = 4), outstanding total FUR conversion and FuMe selectivity (~100%) can be achieved. However, the catalyst gets progressively deactivated in successive catalytic runs under the studied reaction conditions, which is attributed to the formation of organic deposits coming from furfural side reactions. © 2021 Elsevier Inc.