2024 journal article

Catalyst-recirculating system in steam explosion pretreatment for producing high-yield of xylooligosaccharides from oat husk

CARBOHYDRATE POLYMERS, 342.

By: M. Ahn*, S. Wang n, J. Kim*, S. You*, C. Jung*, H. Seong*, J. Choi*, S. Park n, I. Choi*, H. Kim*

author keywords: Catalyst -recirculating system; Autohydrolysis; Liquified catalyst; Xylooligosaccharides; Aspen validation; Steam explosion pretreatment
UN Sustainable Development Goal Categories
Source: Web Of Science
Added: July 17, 2024

We propose a closed-loop pretreatment process, wherein volatiles produced during steam explosion pretreatment were recovered and reintroduced as acid catalysts into the pretreatment system. The volatiles were separated through a drastic decompression process followed by a steam explosion process and recovered as a liquified catalyst (LFC) through a heat exchanger. The LFC effectively served as an acid catalyst for hemicellulose hydrolysis, significantly decreasing residence time from 90 min to 30 min to achieve 80 % conversion yield at 170 °C. Hydrolysates with high content of lower molecular weight oligomeric sugars were obtained using LFC, and were considered advantageous for application as prebiotics. These results are attributed to the complementary features of acetic acid and furfural contained within the LFC. Computational simulation using Aspen Plus was used to investigate the effects of recycling on LFC, and it demonstrated the feasibility of the catalyst-recirculating system. A validation study was conducted based on simulation results to predict the actual performance of the proposed pretreatment system. Based on these results, the recirculating system was predicted to improve the conversion yield and low-molecular weight oligomers yield by 1.5-fold and 1.6-fold, respectively.