Enhanced production of xylose from corncob hydrolysis with oxalic acid as catalyst

Abstract

The acid-catalyzed treatment was a conventional process for xylose production from corncob. To increase the release of xylose and to reduce the by-products formation and water usage, the oxalic acid was used as catalyst to hydrolyze the corncob and the hydrolytic conditions were investigated. The highest xylose yield of 32.7 g L, representing 96.1% of total theoretical xylose yield, was obtained using 1.2% oxalic acid after hydrolysis for 120 min at 130 °C, which was more than 10% higher than that of sulfuric acid-catalyzed hydrolysis. Mixed acids-catalyzed hydrolysis performed a synergistic effect for xylose production and 31.7 g L of xylose was reached after reacting for 90 min with oxalic acid and sulfuric acid at a ratio of 1:4 (w/w). A kinetic model was developed to elucidate the competitive reaction between xylose formation and its degradation in the hydrolysis process, and the experimental data obtained in this study were perfectly in agreement with that of predicted from the model. Furthermore, the final xylose yield of 85% was achieved after purification and crystallization. It was demonstrated that xylose production from the corncob hydrolysis with oxalic acid as the catalyst was an effective alternative to the traditional sulfuric acid-based hydrolysis.

Kinetic Study of Acid Hydrolysis of Corn Cob to Xylose

“…Corncob, an important agricultural residue from the corn processing industry, has received increasing attention worldwide due to its high carbohydrate contents and high energy densities. And it has been considered as one of the most suitable biomasses with potential for the production of various high value-added chemicals such as xylose [3].…”

Room Temperature Oxalic Acid‐Catalyzed, Ambient Pressure Dried, and Cost‐Effective Synthesis of Polybenzoxazine Aerogels for Thermal Insulation

“…In recent years, oxalic acid has been used as a cost-effective and versatile organic catalyst for various chemical reactions. [29][30][31] Moreover, Dunkers and Ishida reported that the weak carboxylic acid sebacic acid might be more suitable for the ring-opening polymerization of benzoxazine than the strong acid early in 1999. [32] These cases provide us a promising way to select oxalic acid as the catalyst to synthesize PBZ aerogels.…”