Concurrent Production of Xylonic Acid and Xylitol from Xylose Through Sustainable Bipolar Membrane Electrodialysis

In the production of chemical compounds from biomass, low-energy separation processes are as critical as advanced valorization of biomass. This study presents an integrated process for the simultaneous production and separation of xylonic acid and xylitol from xylose. A one-pot catalytic reaction using a 5 wt % Pt/activated carbon (AC) catalyst was developed for the concurrent conversion of xylose to xylonic acid (dehydrogenation product) and xylitol (hydrogenation product) under ambient conditions via internal hydrogen transfer. This catalytic reaction was conducted in a basic environment without external hydrogen sources, achieving productivity of 37.5 g L–1 h–1 for each product. Subsequent separation was performed using a bipolar membrane electrodialysis (BMED) for the simultaneous isolation of xylitol, xylonic acid, and potassium hydroxide. The operating conditions for the BMED process were meticulously optimized with respect to electrolyte type, electrolyte concentration, and operating temperature. The optimized BMED system successfully demonstrated a simultaneous separation of three chemicals in a single process, showing 46.4% lower specific energy consumption than that under standard operating conditions. This integrated process exemplifies a sustainable and efficient biorefinery approach for the valorization of biomass feedstock.