resumo
Furfural is an industrial renewable platform chemical, which can be converted to useful furanics such as alpha-angelica lactone, carboxylic acids such as levulinic acid and valeric acid, or to higher carbon content products via condensation routes for producing drop-in fuel replacements and chemicals with diverse applications. These important conversion processes may be carried out in selective fashions, although they require adequate catalysts. They were successfully carried out using versatile, stable silica-wrapped niobium oxide nanostructured catalysts. For example, alpha-angelica lactone was converted in an integrated fashion to ethyl levulinate in 90% yield, and the esterification of levulinic and valeric acids gave ethyl levulinate in quantitative yield and ethyl valerate in 90% yield, respectively, at 140 degrees C. Catalytic, mechanistic and kinetic modelling studies shed light on the influence of the materials properties on the catalytic performances. These catalysts outperformed pure Nb2O5, as well as hydrothermally synthesized composites consisting of Nb2O5 nanoparticles embedded in a mesoporous siliceous matrix. Reaction and substrate scopes may be considerably broadened in the context of the chemical valorisation of biomass, using stable solid acid catalysts consisting of nanostructured silica-niobia which outperformed pure niobia and other catalysts.
palavras-chave
LAYERED DOUBLE HYDROXIDES; ALPHA-ANGELICA LACTONE; ALDOL CONDENSATION; LEVULINIC ACID; MIXED OXIDES; PHYSICOCHEMICAL PROPERTIES; SURFACE-PROPERTIES; ETHYL LEVULINATE; ACETONE; PERFORMANCE
categoria
Chemistry; Science & Technology - Other Topics
autores
Antunes, MM; Skrodczky, K; Cabanelas, PS; Pinna, N; Russo, PA; Valente, AA
nossos autores
Anabela Tavares Aguiar Valente
Investigador Principal
Maria Margarida Feitor Pintão Moreno Antunes
Investigador Júnior
Nicola Pinna
InvestigadorProjectos
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
agradecimentos
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MCTES (PIDDAC). The position held by M. M. A. was funded by national funds (OE), through FCT, I. P., in the scope of the framework contract envisaged in the numbers 4, 5 and 6 of article 23 of the Decree-Law 57/2016 of 29 August, changed by Law 57/2017 of 19 July (https://doi.org/10.54499/DL57/2016/CP1482/CT0062).