abstract
Mesostructured zirconium-based mixed oxides (MZM) are versatile solid acid catalysts for the chemical valorisation of biomass, within sugar and fatty acid platforms of biorefineries. MZM catalysts containing tungsten and/or aluminium were prepared via a templating route that allows the texture and acid properties to be improved. Their catalytic potential was explored for synthesising different types of interesting oxygenated fuel bio-additives, specifically levulinate esters, furfuryl alkyl ethers and glycerol acetals of the type 1,3-dioxolane and 1,3-dioxane. Levulinate esters are synthesised from furfuryl alcohol (FA), which is produced industrially from lignocelluloses; the acetals are obtained from glycerol, which is a coproduct of the industrial production of biodiesel. The performances of the MZM catalysts have been compared with those of zirconium-(tungsten and/or aluminium) mixed oxides synthesised via conventional co-precipitation (without a template). Structure-activity relationships were established which reveal advantages of the templating route used for the synthesis of the MZM catalysts. The MZM catalysts were more active and led to higher total yields of bio-additives (e.g. up to 86% yield at 100% FA conversion, 140 degrees C, 30 min reaction) than the catalysts prepared by co-precipitation (e.g. up to 45% yield at 88% FA conversion), under similar reaction conditions. Detailed catalytic and characterisation studies were carried out for the used catalysts. (C) 2014 Elsevier B.V. All rights reserved.
keywords
ETHYL LEVULINATE; HETEROGENEOUS CATALYSIS; LIGNOCELLULOSIC BIOMASS; FUEL ADDITIVES; CONVERSION; TUNGSTEN; DEHYDRATION; ACETALIZATION; HYDROGENATION; ISOMERIZATION
subject category
Chemistry; Environmental Sciences & Ecology
authors
Neves, P; Russo, PA; Fernandes, A; Antunes, MM; Farinha, J; Pillinger, M; Ribeiro, MF; Castanheiro, JE; Valente, AA
our authors
Anabela Tavares Aguiar Valente
Principal Researcher
Maria Margarida Feitor Pintão Moreno Antunes
Junior Researcher
Martyn Pillinger
Principal Researcher
Patrícia Alexandra Ferreira Russo
Post-doc Fellowship
Patrícia dos Santos Neves
Assistant Researcheracknowledgements
This work was partly financed by FEDER (Fundo Europeu de Desenvolvimento Regional) through COMPETE (Programa Operacional Factores de Competitividade) and by national funds through the FCT (Fundacao para a Ciencia e a Tecnologia) within the project CICECO - FCOMP-01-0124-FEDER-037271 (FCT ref. PEst-C/CTM/LA0011/2013), projects PTDC/CTM/09836/2008 and PTDC/CTM-POL/114579/2009. The FCT and the European Union are acknowledged for grants to P.N. (SFRH/BPD/73540/2010), P.A.R. (SFRH/BPD/79910/2011) and M.M. Antunes (SFRH/BPD/89068/2012) cofunded by MCTES and the ESF through the programme POPH of QREN. The authors wish to thank Dr Rosario Soares for assistance with the powder X-ray diffraction data measurements.