Ultrafast improvement of cellulose accessibility via non-dissolving pretreatment with LiBr center dot 3H(2)O under room temperature

The development of sustainable and effective pretreatment methods to improve the accessibility of cellulose is of vital importance for its utilization. Herein, a novel high-efficiency pretreatment method based on lithium bro-mide trihydrate (LBTH) was established, which realized the fast improvement of cellulose accessibility under ambient conditions without dissolution of cellulose. The cellulose I structure of microcrystalline cellulose (MCC) was transformed into amorphous structure just within 5 min of LBTH pretreatment, and the crystallinity was reduced from 79.1 to 19.9%. After pretreatment for 30 min, the BET surface area of MCC increased from 2.1 to 125.9 m(2)/g. Particularly, the pretreated cellulose could be near-completely saccharified to glucose (98.3%) with ultra-low enzyme dosage (2.5 mg protein/g-glucan) just within 24 h, while the conversion of untreated MCC under the same conditions was only 16.7%. Additionally, this non-dissolving pretreatment is beneficial to the separation and recycling of LBTH, guaranteeing a clean and sustainable process.