Dowex 1X4 and Dowex 1X8 as substitute of Diaion MA03SS in simulated moving bed chromatographic separation of sulfuric acid and sugars in concentrated sulfuric acid hydrolysates of bamboo

• Two commercially available resins suitable for simulated moving bed were successfully tested.
• Separation tests of the two resins were based on H2SO4 hydrolysates of bamboo.
• Dowex 1Xn (n = 4, 8) showed performances comparable to those of Diaion MA03SS.

To find commercially available ion exchange resins comparable to a strong-base anion exchange resin Diaion MA03SS, which is specialized for the separation of sulfuric acid and sugars in concentrated sulfuric acid hydrolysates of non-food biomass by means of a simulated moving bed (SMB) chromatography, the screening test of 6 kinds of commercially available resins containing quaternary ammonium groups was carried out by a batch column-mode chromatographic separation of glucose and sulfuric acid at 50 °C. Based on results of the screening test, Dowex 1X4 and Dowex 1X8 were selected as replacements of Diaion MA03SS. The following SMB study using Diaion MA03SS, Dowex 1X4 and Dowex 1X8 at 50 °C clarified that Dowex 1X8 showed performances almost the same as those of Diaion MA03SS in the separations of sulfuric acid and sugars (mainly glucose and xylose) in hydrolysates of bamboo with 27 wt% sulfuric acid under the averaged flow rate of feed loading from 0.136 to 0.273 L/(h L-resin). For Dowex 1X8, recoveries of sulfuric acid were 90.5–93.4% and recoveries of glucose and xylose were 94.9–99.7% and 82.8–88.3%, respectively. Dowex 1X4 showed slightly higher recoveries for three solutes; namely sulfuric acid recoveries were 95.0–95.5% and glucose and xylose recoveries were 100–101% and 86.1–91.7%, respectively. However, the highest averaged flow rate of feed loading for Dowex 1X4 was 0.205 L/(h L-resin) because of the higher column pressure loss owing to its high shrinking in 30 wt% sulfuric acid. Thus, it became clear that Dowex 1X8 exhibit excellent performances comparable to or higher than those of Diaion MA03SS in the SMB chromatographic separation of sulfuric acid and sugars in concentrated sulfuric acid hydrolysate of bamboo.