LiCl/HCl ionic solution for efficient conversion of lignocellulose into glucose under mild conditions

Molten salt hydrates in diluted acid solutions are a great medium to dissolve cellulose by interrupting the formation of intra-and inter -hydrogen bonding in the crystalline structure of cellulose. In this study, lithium chloride in diluted HCl is used as an inexpensive and efficient way to dissolve and hydrolyze cellulose into glucose. 23 completely randomized design (CRD), including three replications at the center point, was applied to evaluate the effect of LiCl concentration, HCl concentration and cellulose concentration with respect to glucose yield. The composition of LiCl/HCl ionic solution for optimal glucose yield at 80 degrees C is determined to be 50wt% of LiCl, 2 wt% of HCl, and 10 wt% of cellulose feedstock. A two stage method is designed for obtaining reducing sugars from sugarcane bagasse in which biomass is treated first with 2 wt% diluted HCl at 100 degrees C for xylose and then with LiCl/HCl ionic solutions in the second stage at 80 degrees C for glucose. Total reducing sugar yield of sugarcane bagasse is up to 94.8 wt% indicating that the developed LiCl/HCl ionic solution has potential to treat cellulose for the production of inexpensive fermentable sugar. (C) 2018 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.