3 ans - à partir au plus tard de mars 2022

PhD position: Noble metals-free heterogeneous catalysts for lignin deoxygenation into aromatics

The PhD project will aim at synthesizing heterogeneous catalysts based on abundant metals, whose key parameters will be optimized: (i) textural properties of the supports, and in particular the stabilization of a hierarchical porosity, (ii) oxophilicity / acidity of the surface, (iii) and fine characteristics of the metals (dispersion, localization and composition). Thus, silica supports with hierarchical porosities will be synthesized, modified by the introduction of different oxide phases (ZrOx, TiOx, AlOx, ZnO), and then the metal phases (Ni, Fe, Co and Cu) will be dispersed in a controlled manner on the surface of the pores to obtain single atome to clustered supported catalysts. These catalysts will be studied for the HDO of model oxygenated molecules (m-cresol, anisole and guaiacol) under moderate hydrogen pressures (2-4 MPa) before being tested on real lignin in a reaction micropilot (IC2MP partner). The properties of the catalysts (activity, aromatic yield, and stability) will be rationalized by DFT studies conducted on the adsorption of model oxygenated molecules, taking into account the effect of H2O, CO and CO2 inhibitors (LPCT partner). All these results will allow the description of the reaction pathway and the obtaining of key kinetic data in real conditions of reaction conducted over lignin (at LRGP partner).

Proposal summary: The transformation of lignocellulosic biomass into fuels or reaction
synthons of interest for fine chemistry is an essential issue for reducing the environmental
impact associated with the use of fossil resources. Contrary to cellulose and hemicellulose,
lignin is a resource that is still not very well valorized, although it is abundantly produced by
the pulp and paper industry and will be an abundant by-product of next generation cellulosic
biorefineries. Different technologies exist for lignin liquefaction, but fast pyrolysis has
undeniable advantages. It can convert 60-75% of lignocellulosic biomass into crude bio-oil, and
it operates continuously, in an inert environment, and without solvent consumption. However,
the bio-oil must be upgraded to be valorized. Containing up to 55% of phenolic compounds, it
is a source of simple aromatic hydrocarbons (BTX). Catalytic hydrodeoxygenation (HDO) is
the most suitable catalytic process to transform phenolic monomers into BTX. The catalyst, by
selectively activating the C-O bonds, will allow the deoxygenation of phenolic compounds
while avoiding their hydrogenation. These two processes are therefore essential to ensure the
economic viability of biorefineries through a better valorization of the lignocellulosic fraction.
The project aims developing original catalysts for the deoxygenation of lignin pyrolysis vapors,
with the goal to improve the yield of aromatic hydrocarbons. In order to gather skils in materials
chemistry, molecular modelling, heterogeneous catalysis and process engineering, the project
team associates 5 laboratories, labelled by CNRS: UCCS (Univ. Lille), IC2MP (Univ. Poitiers),
and L2CM, LPCT, and LRGP (all three from Univ. Lorraine). The skills thus gathered allow
the development of a multi-scale approach, from ab initio modeling at the molecular scale of
surfaces to the study of catalyst performance on lignin pyrolysis vapors from a continuous
hydropyrolysis process.

Starting date: Flexible, until march 2022

Application: CV + motivation letter by email to the supervisors

Sebastien Royer, Professor Université de Lille, France (sebastien.royer@univ-lille.fr) & Nadia Canilho, MCF Université de Lorraine, France (nadia.canilho@univ-lorraine.fr)

Laboratory information:
French partner: http://uccs.univ-lille1.fr/index.php/en/heterogeneous-catalysis/matcat

Approx. 1600 euros net/month

Dr. Nadia Canilho - Contacter
L2CM - Laboratoire Lorraine de Chimie Moléculaire à Nancy
Université de Lorraine

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5 ans

Chaire de professeur junior

Chaire de professeur junior

Profil recherche : Métaux abondants pour la synthèse organique asymétrique.

Composante d'enseignement : UFR Sciences Fondamentales et Appliquées (SciFA).

Les candidatures doivent être déposées en version numérique sur Galaxie (module FIDIS (fil de l'eau)*) selon le calendrier disponible sur le site de L'Université de Lorraine. Pour plus d'information, consultez la fiche de poste.

5-6 mois début janvier 2023

Stage M2 : Organic synthesis and encapsulation of Aggregation Induced Emission (AIE) dyes for phototheranostic applications

Context: Light-assisted imaging, therapeutic and merged (theranostic) approaches are ever-expanding in medicine. Photothermal therapy (PTT) coupled to photoacoustic and fluorescence imaging, which relies on heat/ultrasound production and fluorescence emission upon light irradiation, stand on the frontline of theranostic approaches under development. In addition, the possibility of bringing energy to the system by biphotonic excitation opens way to access the near infrared window, which is more suitable for in vivo applications. In this domain, there is a need of novel agents which could efficiently integrate these multiple features in one structure. Fluorophores combining properties of aggregation-induced emission (AIE) and two-photon absorption are promising candidates.

Research objectives: The aim of this study will concern the synthesis of dyes from the families of quinoline-malonitrile (QM), dicyanomethylene-2H-chromene (DCM) and benzo-bis-thiadiazole (BBTD). Structural modulations of the organic scaffold via modification of the substituents will be conducted to optimize the structure and achieve AIE and two-photon absorbing properties. The work will be mostly dedicated to the multistep organic synthesis of already known and novel compounds.