Screening of the catalysts for the fructose dehydration into 5 hydroxymethylfurfural in biphasic conditions at low temperature

Details

Supervisors

Debecker, Damien P.

Faculty

Faculté des bioingénieurs

Degree label

Master [120] : bioingénieur en chimie et bioindustries, à finalité spécialisée

Abstract

The extended use of fossil resources for the production of chemicals and as a fuel poses several environmental problems. Biomass can be used as substitute renewable raw material for petrochemical resources to produce molecules similar to those from the petrochemistry. The objective of this master thesis is to investigate the potential acidic catalysts for the fructose dehydration into hydroxymethylfurfural (HMF) in a biphasic MIBK:H2O system at temperatures suitable for enzymes. The obtention of such catalyst would allow the preparation of a bifunctional chemo-enzymatic catalyst to directly transform glucose into HMF in one-step. The benefit of doing the transformation in one-step is to avoid the recovery and purification costs between different reactions. Using a Glucose Isomerase enzyme allows to obtain fructose from glucose with high selectivity. Glucose is the most available and abundant monomer obtainable from biomass. Hydroxymethylfurfural (HMF) is a platform chemical that can be obtained from biomass and further transformed into many different molecules such as monomers, fine chemicals or even fuels. In this work, the catalysts for the fructose dehydration in biphasic conditions at relatively low temperatures have been investigated. The most efficient catalysts identified is the ion exchange resin Amberlyst-15. This work also showed the impact of both the acidity of the catalyst and the hydrophobicity of its surface. For the acidity, both the number of acid sites and the strength of these sites seems to have a positive impact on the efficiency of the catalyst. A higher hydrophobicity allowed a better extraction of the HMF in the organic phase of the system after its production leading to higher selectivities. However, none of the investigated catalysts have shown sufficiently high performances to be used with an enzyme and moreover, a negative impact of the Amberlyst-15 on the enzyme has been detected. The knowledge gained from this work thus allows to restraints the following researches to the investigation of other strongly acidic resins such as Nafion-117 as well as the screening of different reaction conditions such as the use of THF in place of MIBK.