Ultrafiltration-based diafiltration for post-delignification fractionation of lignin from a deep eutectic solvent comprised of lactic acid and choline chloride

Pressure-driven membrane processes for the recovery and recycling of deep eutectic solvents: A seaweed biorefinery case study

Deep eutectic solvents (DES) are green alternatives for conventional solvents. They have gained attention for their potential to extract valuable compounds from biomass, such as seaweed. In this framework, a case study was developed to assess the feasibility of pressure-driven membrane processes as an efficient tool for the recovery of deep eutectic solvents and targeted biomolecules. For this purpose, a mixture composed of the DES choline chloride - ethylene glycol (ChCl-EG) 1:2, water and alginate was made to mimic a DES extraction from seaweed. An integrated separation process design was proposed where ultrafiltration-diafiltration-nanofiltration (UF-DF-NF) was coupled. UF and DF were found to be effective for the separation of alginate with an 85 % yield. DES was likewise recovered by 93 %, proving the membrane filtrations' technical feasibility. The NF performance to separate the DES from the water, for its recycling, laid by a 45 %-50 % retention and a final concentrated DES solution of 18 %(v/v).

Recent advances in biorefineries based on lignin extraction using deep eutectic solvents: A review

Considering the urgent need for alternative biorefinery schemes based on sustainable development, this review aims to summarize the state-of-the-art in the use of deep eutectic solvent pretreatment to fractionate lignocellulose, with a focus on lignin recovery. For that, the key parameters influencing the process are discussed, as well as various strategies to enhance this pretreatment efficiency are explored. Moreover, this review describes the challenges and opportunities associated with the valorization of extraction-derived streams and highlights recent advancements in solvent recovery techniques. Furthermore, the utilization of computational models for process design and optimization is introduced, as the initial attempts at the economic and environmental assessment of this lignocellulosic bioprocess based on deep eutectic solvents. Overall, this review offers a comprehensive perspective on the recent advances in this emerging field and serves as a foundation for further research on the potential integration of deep eutectic pretreatment in sustainable multi-product biorefinery schemes.

Controllable recovery and recycling of carboxylic acid-polyalcohol deep eutectic solvent for biomass pretreatment with electronically-controlled chemical methodology

Pretreatment of lignocellulosic biomass using deep eutectic solvent (DES) has been demonstrated environmental and valid. Co-existing of donor and acceptor of hydrogen bond makes DES composition more complicated than traditional solvents, which limits their further scale-up utilization. Advances in biomass pretreatment using green solvent DES should excogitate efficient methodology for DES recycling. Electronically-controlled chemical methodology was first put forward to resolve recovery and recycling issue of DES lactic acid-ethylene glycol after biomass pretreatment. The methodology worked based on selectively migrating of lactate Lac^- and reserving of ethylene glycol using BP-A-BP bipolar membrane electrodialysis (BMED). Impact of primary factors on DES recovery was carefully studied. Lowest energy consumption for specific DES recovery reached 10.4 kw·h/kg and highest DES recovery rate approached 97.6 %. Cognition acquired from this research indicated a promising and efficient strategy for carboxylic acid-polyalcohol DES recovery with novel electronically-controlled chemical methodology.