Extraction and electrochemical depolymerisation of lignin for generation of high added value extracts

For the last decade, the pretreatment of lignocellulosic biomass (LCB) with deep eutectic solvents (DES) have been largely used to improve the saccharification efficiency for fuel production [1] or to extract lignin with high reactivity [2].These solvents are attractive as they are cheap, easy to prepare and present low toxicity [3]. However, the scale up of DES-based LCB valorization processes is still limited due to for example the lack of knowledge in the impact of DES and biomass types on LCB fractionation efficiency.

                The position is funded by an ANR grant for the “Assembly of green PROcesses for optimal biomass Valorization” (APPROV(E)) project, which aims at the development of a lab-scale DES-based biorefinery. APROV(E) will cover all the biorefinery steps from LCB fractionation with DES until lignin, cellulose and hemicellulose streams, and valorization of lignin via electrochemical depolymerisation.

The selected candidate will work on the lignin extraction with DES and its electrochemical depolymerisation to recover high added value extracts. The sources and nature of lignin as well as the experimental conditions used during both extraction and electrochemical depolymerisation play an important role on the structure of lignin and products obtained. These parameters will be optimized and the depolymerisation products will be characterized by several techniques such as GC-MS, SEC, cyclic voltammetry or UV-Vis spectroscopy to determine their structure and antioxidant activity [4]. Recovery of the desired depolymerized products is crucial and various techniques will be tested for this purpose, such as classical liquid-liquid extraction carried out after the electrolysis step or in situ extraction via emulsion techniques that were shown to limit overoxidation of the desired products [5].

L’IPHC, unité mixte de recherche sous cotutelle du CNRS et de l’Université de Strasbourg (UMR7178), est un exemple de réussite de la pluridisciplinarité où des équipes de recherche de cultures scientifiques différentes (écologie, physiologie et éthologie, chimie et physique subatomique) développent des programmes pluridisciplinaires de très haut niveau avec pour socle l’instrumentation scientifique. 

•  Academic background: chemistry with specialization in electrochemistry, chemical engineering, green and sustainable chemistry, biorefinery or a related field. 
• Skills: strong laboratory and analytical skills; Knowledge of analytical techniques such as GC-MS, SEC, cyclic voltammetry, UV-Vis spectroscopy will be an asset. 
• Attributes: self-motivated, able to work both independently and as part of a team.
• Motivations: the candidate should be enthusiastic and outgoing when searching for solutions to challenges that will arise during the experimental work.