Adsorption materials for the recovery and separation of biobased molecules

In this thesis we studied several strategies to improve adsorption technology for the adsorption of biobased molecules. These strategies are based on the adsorbent as well as the adsorption process. A systematic investigation of the chemical and physical structure of resin materials and their relation to adsorption properties was performed. The separation of 5-hydroxymethylfurfural (HMF) from glucose was studied for this purpose with different adsorbents and we found that the hypercrosslinked resin Dowex Optipore L-493 (Optipore) showed the best results due to the highly accessible BET surface area. This also ensured fast kinetic adsorption properties which was shown with zero length column experiments and breakthrough curves. Different resins were incorporated in mixed matrix membranes to further enhance the kinetic properties of the adsorption system. Due to the open structure of the MMMs, the MMMs show improved adsorption capacity and fast adsorption rates at high flow rates, which allows for high throughput application of MMMs for HMF separation. Furthermore this research shows that MMMs could be a good alternative for traditional packed beds for the adsorption of small molecules. Molecular imprinting was used to increase the selectivity of the adsorbent. The molecular imprinted membranes investigated show clear pH transitions and fast kinetics. Consequently, molecular imprinting of membranes (MIMs) seems to be a very interesting technology for the selective recovery or separation of specific molecules from complex feed mixtures and therefore the downstream processing in biorefinery. However the membranes showed very stringent requirements regarding the sorption conditions which is in conflict with the process streams in the downstream processing of biorefinery products

Performance analysis of aromatic adsorptive resins for the effective removal of furan derivatives from glucose

BACKGROUND Many countries have set goals to replace conventional energy sources with renewable energy sources. This has led to investigations into the use of lignocellulosic biomass as a feedstock for renewable fuels and base chemicals. Unfortunately hydrolysation of this biomass introduces impurities that are toxic to the fermentation bacteria. This study aims to find the key adsorber properties for the separation of toxic 5-hydroxymethylfurfural (HMF) from glucose. RESULTS Batch adsorption experiments on styrene based (anion exchange) adsorbers showed that a high surface area is a key property for effective HMF adsorption. Introduction of polar groups in the form of anion exchange groups appears to increase the HMF-affinity of the resin material, unfortunately these groups also introduce affinity for glucose. Competitive adsorption studies of HMF and glucose showed that glucose does not affect HMF adsorption in any of the resins. CONCLUSION Furan derivatives can be removed from water and sugar solutions with styrene based (anion exchange) polymeric resins. For efficient removal, a high surface area of the resin is a key property. Dowex Optipore L-493 shows the best specific HMF adsorption and no specificity for glucose, which makes it an excellent adsorber for HMF removal from hydrolysate for the fermentation of glucose. © 2013 Society of Chemical Industr

Performance analysis of aromatic adsorptive resins for the effective removal of furan derivatives from glucose

\u3cbr/\u3eBACKGROUND\u3cbr/\u3eMany countries have set goals to replace conventional energy sources with renewable energy sources. This has led to investigations into the use of lignocellulosic biomass as a feedstock for renewable fuels and base chemicals. Unfortunately hydrolysation of this biomass introduces impurities that are toxic to the fermentation bacteria. This study aims to find the key adsorber properties for the separation of toxic 5-hydroxymethylfurfural (HMF) from glucose.\u3cbr/\u3eRESULTS\u3cbr/\u3eBatch adsorption experiments on styrene based (anion exchange) adsorbers showed that a high surface area is a key property for effective HMF adsorption. Introduction of polar groups in the form of anion exchange groups appears to increase the HMF-affinity of the resin material, unfortunately these groups also introduce affinity for glucose. Competitive adsorption studies of HMF and glucose showed that glucose does not affect HMF adsorption in any of the resins.\u3cbr/\u3eCONCLUSION\u3cbr/\u3eFuran derivatives can be removed from water and sugar solutions with styrene based (anion exchange) polymeric resins. For efficient removal, a high surface area of the resin is a key property. Dowex Optipore L-493 shows the best specific HMF adsorption and no specificity for glucose, which makes it an excellent adsorber for HMF removal from hydrolysate for the fermentation of glucose. © 2013 Society of Chemical Industry\u3cbr/\u3

Adsorption kinetics of Dowex\u3csup\u3eTM\u3c/sup\u3e Optipore\u3csup\u3eTM\u3c/sup\u3e L493 for the removal of the furan 5-hydroxymethylfurfural from sugar

\u3cp\u3eBACKGROUND: Recently much research has been focused on the production and refinery of biobased fuels. The production of biofuels derived from lignocellulosic biomass is recognized as a promising route to produce biobased fuels responsibly. Often, product streams (e.g. glucose) still contain small amounts of undesired components (e.g. furans such as HMF). This study focuses on the removal of furans produced during the fermentation. In earlier work, styrene based resins have been identified as promising materials for this separation. In this work the kinetic properties of the most promising resin: Dowex\u3csup\u3eTM\u3c/sup\u3e Optipore\u3csup\u3eTM\u3c/sup\u3e L493 are studied. RESULTS: The diffusion coefficient of 5 mg L\u3csup\u3e-1\u3c/sup\u3e HMF was ∼8×10\u3csup\u3e-12\u3c/sup\u3e m\u3csup\u3e2\u3c/sup\u3e s\u3csup\u3e-1\u3c/sup\u3e in water and 3.0×10\u3csup\u3e-12\u3c/sup\u3e m\u3csup\u3e2\u3c/sup\u3e s\u3csup\u3e-1\u3c/sup\u3e in a glucose solution. The reduced diffusion coefficient in the particle when glucose is present is caused by the higher viscosity of the glucose solution and it indicates that diffusion is controlled by surface and pore diffusion. The breakthrough curves of HMF on Optipore showed that the column is very efficient under conditions of interest. CONCLUSION: This study shows that Optipore is a much more efficient resin for HMF removal than currently used resins. Its fast kinetics and capacity make it possible to efficiently remove HMF from glucose solutions.\u3c/p\u3