Abstract
The main goal of this work is the exploitation of the lignin fraction present in grape stalks (GS) to produce high-value-added chemicals via non-conventional and sustainable means in a three-way valorisation process. Firstly, delignification using NaOH and Natural Deep Eutectic Solvents (NaDESs), via microwave-assisted extraction (MAE), was performed using a bicomponent (choline chloride + lactic acid) and a tricomponent (choline chloride + lactic acid + glycerol) NaDES and giving engaging MAE results in terms of delignification (around 80%). The liquid fractions obtained from MAE, using NaDESs and NaOH, were analysed, with all of them displaying promising antioxidant activity compared to the standards. Subsequently, oxidation was carried out via microwave (MW) heating, with the lignins that were isolated after the delignification step mainly yielding long-chain fatty acids (LCFA), which are valuable for bio-fuel production. However, when GS was used as the starting material, 16% wt. of bioaromatics (mainly vanillin and syringaldehyde) was produced. Oxidation therefore provides two further pathways for the exploitation of the lignin fraction from this lignocellulosic waste.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Chemical Engineering and Processing - Process Intensification
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
