Development of Sustainable Biorefinery Processes Applying Deep Eutectic Solvents to Agrofood Wastes

Abstract

The growing demand for renewable energies and the application of sustainable and economically viable biorefinery processes have increased the study and application of lignocellulosic biomass. However, due to lignocellulosic biomass recalcitrance hindering its efficient utilization, the pretreatment in the biorefinery is an essential stage for success in the process. Therefore, Deep Eutectic Solvent (DES) has emerged as a promising green pretreatment. During this study, the effect of choline chloride [ChCl]:glycerol and [ChCl]:urea on sugarcane bagasse and brewery bagasse is evaluated. Results have demonstrated that using [ChCl]:glycerol in SCB reduced about 80% and 15% for acid-soluble lignin and Klason lignin, respectively, and improved efficiency on saccharification yields, achieving conversions of 60, 80, and 100% for glucan, xylan, and arabinan, correspondingly. In the case of BSG saccharification yields, about 65% and 98% are attained for glucan and xylan, respectively, when [ChCl]:glycerol was employed. These results confirm the effectiveness and facility of DES pretreatment as a suitable method that can improve the biorefinery processes.

Deep eutectic solvents for lignin isolation

“…The reported result showed 80 and 15% acid-soluble lignin and Klason lignin isolation, respectively. In addition, it showed increment of saccharification yields with 60, 80, and 100% of dextran, xylan, and arabinoxylan, respectively [96].…”

“…In the study, wheat straw pretreatment was conducted by utilizing chloride: lactic acid (1:2) and DES solution (1:20 solid-to-liquid ratio) at various temperatures (90, 120, 150, and 180°C) for 6 and 12 h. It is reported that the yields of lignin were increased from 15.26 to 81.54% and purity of 91.33% with temperature increase from 90 to 180°C. Thus, the optimal temperature obtained in the pretreatment of wheat straw for lignin isolation was 150°C for 6 h [96]. Lou et al conducted a comprehensive analysis of lignin nanoparticle synthesis from wheat straw using ChCl: LA-based DES.…”