Dehydratisierung von D-Fructose sowie Oxidation von 5-HMF : Möglichkeiten der Prozessintensivierung durch Mehrphasensystem
Kükrek, Murhat; Palkovits, Regina (Thesis advisor); Rose, Markus (Thesis advisor)
Aachen (2018, 2019)
Dissertation / PhD Thesis
Dissertation, RWTH Aachen University, 2018
Due to the scarcity of crude oil reserves and the resulting rising prices as well as the serious discussions on climate protection, the chemical industry is looking for cost-effective and widely available sustainable alternative sources of raw materials. An alternative are 2,5-furandicarboxylic acid (FDCA) and 2,5-diformylfuran (FDA), which can be manufactured on a sugar basis. For this purpose, D-Fructose or glucose are converted by dehydration to 5-hydroxymethylfurfural (5-HMF). 5-HMF itself is considered by U.S. Department of Energy one of the top 10 platform chemicals based on lignocellulose. The oxidation of 5-HMF makes FDA (biofuel feed), FDCA (monomer) and maleic anhydride (monomer) available. The present thesis describes the selective dehydration of D-Fructose into 5-HMF and the simultaneous extraction as well as the oxidation on a V2O5 / TiO2 to FDA. For this purpose, the dehydration of D-Fructose in the ionic liquid was the variation of various parameters, which have an influence on the product selectivity and the conversion. In addition, the implementation of the oxidation of 5-HMF in different organic solvents followed with temperature variations on a commercial catalyst and the determination of the conversion and the selectivity. The organic solvents were additionally tested for their suitability as extractants for 5-HMF and FDA from the ionic liquid. As a catalyst, the choice fell on vanadium oxide supported on titanium dioxide, since it is commercially available and inexpensive to manufacture for industrial use. The combination of dehydration of D-Fructose and simultaneous oxidation of 5-HMF in the extraction phase was carried out in a two-phase system with the goal of process intensification. The fixation of the catalyst was carried out by means of a frit spatially in the region of the upper phase, which could exclude the direct contact between the catalyst and ionic liquid. In addition to the multiphase synthesis, the reaction kinetics of the dehydration and of the oxidation were investigated in order to gain an impression of which step or partial reaction the reaction rate of the entire system is dependent on.