LAUSR

In this work, a simple two-stage pretreatment (TSP) was utilized to improve hemicellulose separation and alleviate lignin condensation and therefore facilitate hemicellulose extraction and subsequent kraft pulping. In contrast to single-stage pretreatment, TSP showed a significant improvement for hemicellulose extraction and hemicellulose degradation and provided an almost identical cellulose loss. The hemicellulose separation efficiency was significantly improved using TSP with 60 min first followed by 30 min. More importantly, proper pretreatment is beneficial to the subsequent delignification; extensive pretreatment can retard delignification.