Comparison of various organic acids for xylo-oligosaccharide productions in terms of pKa values and combined severity

Abstract Background Methods to produce XOS have been intensively investigated, including enzymatic hydrolysis, steam explosion, and acid hydrolysis. Acid hydrolysis is currently the most widely used method due its advantages of fewer processing steps, stronger raw material adaptability, higher yield, better reproducibility. Especially, organic acids such as acetic acid, formic xylonic work compared with mineral acids. However, catalytic mechanism different has little studied. In this paper, four acids, glycolic lactic were selected compare their hydrolytic effects. Results Using pKa values benchmark, yield xylo-oligosaccharide (XOS) increased increasing value pKa. The was 37% when hydrolyzed by 5% (pKa = 4.75) at 170 ? for 20 min. Combined severity (CS), a parameter associated temperature reaction time proposed, proposed evaluate effect. results CS consistent that on both inhibitor. Conclusion based combined severity, time, concluded preferred catalyst. Combining techno-economic analysis environmental benefits, process lower factory production costs, it also an important metabolite carbon source wastewater anaerobic biological treatment. conclusion, xylo-oligosaccharides inexpensive, environment-friendly, sustainable technique.