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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 Industry

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BACKGROUND Amino acids are valuable intermediates in the biobased economy for the production of chemicals. Electro‐membrane processes combined with enzymatic modification have been investigated as an alternative technology for the fractionation of a mixture of amino acids with almost identical charge behavior. Up to now, the modification and subsequent separation were performed in two separate reactors. An interesting approach is the integration of both unit operations into one single device using mixed matrix membranes (MMMs) as platform for enzymatic conversion. RESULTS MMMs containing the enzyme glutamic acid decarboxylase (GAD, EC 4.1.1.15) Relizyme EP403/S as carrier were prepared showing satisfactory mechanical stability and enzymatic activity for L‐glutamic acid conversion into γ‐aminobutyric acid (GABA). ED with integrated MMM for simultaneous enzymatic decarboxylation of L‐glutamic acid to GABA (33% conversion) and further separation of L‐aspartic acid and unconverted L‐glutamic acid from GABA was successful leading to current efficiency of 40% and low energy consumption of 3 kWh kg‐1. CONCLUSIONS Together with the high mechanical stability obtained for the MMMs, this opens the route towards process intensification, combining enzymatic conversion and separation with electrodialysis in one integrated process for the successful isolation of amino acids for biorefinery applications. © 2013 Society of Chemical Industry