In Situ Chemical Locking of Acetates During Xylo-Oligosaccharide Preparation by Lignocellulose Acidolysis

Xylo-oligosaccharides with high value could be obtained by acidolysis of lignocellulosic biomass with acetic acid, which was an urgent problem to solve for the separation of acetic acid from crude xylo-oligosaccharides solution. Four neutralizers, CaCO3, CaO, Na2CO3, and NaOH, were used for in situ chemically locking the acetic acid in the acidolyzed hydrolysate of corncob. The chemically locked hydrolysate was analyzed and compared using vacuum evaporation and spray drying. After CaCO3, CaO, Na2CO3, and NaOH treatment, the locking rates of acetic acid were 92.62%, 94.89%, 95.05%, and 95.58%, respectively, and 39.55 g, 41.13 g, 41.78 g, and 41.87 g of the compound of xylo-oligosaccharide and acetate were obtained. Sodium neutralizer had lesser effect on xylo-oligosaccharide content, and Na2CO3 was the best chemical for locking acetic acid among these four neutralizers. This process provides a novel method for effectively utilizing acetic acid during the industrial production of xylo-oligosaccharides via acetic acid.

Automated summary

This study investigated the efficient production of acetic acid xylo-oligosaccharides by chemically locking acetic acid using different neutralizers. The results showed that Na2CO3 was the best chemical for locking acetic acid among the tested neutralizers.