Doctoral thesis (M/F) - Elucidation of the electrochemical activity of biochar in bioprocesses

General information

To apply: http://doctorat.univ-lorraine.fr/fr/les-ecoles-doctorales/c2mp/offres-de-these/lue-decryptage-de-lactivite-electrochimique-du-biochar

Place of work: LCPME and LRGP at Université de Lorraine, Nancy, France. Collaboration with the group of Prof Manuel Garcia-Perez at Washington State University

Type of contract: International doctoral contract

Contract duration: 36 months 

Hiring date: October 2024

Working hours: Full time

Gross salary: €2,100

Level of education required: Master

Funding sources: Lorraine Université d’Excellence, https://www.univ-lorraine.fr/lue/en/home/

Description of the research topic

The PhD project has the ambition to clarify the relationship between biochar properties, especially conductivity and electrochemical reactivity, microbial ecology of biofilms growing on this biochar and biogas production in bioreactors enriched with such biochar. Indeed, there is reports in the literature on the role of redox-active/conductive biochar amendment on the biogas production from anaerobic bioreactors. One limitation of such study lies on the relatively complex texture of the particle materials that does allow well controlled fundamental investigations in a systematic approach.

This PhD project propose to initiate the study by synthesizing well-defined biochars from controlled biomass sources (including model biomass macromolecules) and under finely tuned pyrolysis conditions (temperature, residence time of the solid, pressure, etc.). These samples will be characterized with a wide range of techniques available at LCPME, before and after exposure to the anaerobic environment from the methanizer of La Bouzule (experimental farm of Université de Lorraine). These characterizations include specialized techniques such as scanning electrochemical microscopy to assess the surface electrochemical reactivity that is involved in the initial interactions with microbes.

A selection of biochar will then be applied to biofilm growth in anaerobic conditions mimicking the environment of an methanizer such as the one of La Bouzule. The ambition is here to get a taxonomic analysis of the microbial population, and to extend the analysis to the transcriptional state of the cell, by analyzing the mRNA involved in redox enzyme production.

The final experimental stage of the project will involve anaerobic bioreactors inoculated with digestates taken from the Bouzule methanizer, and fed with a selection of biochar particles for evaluating the role of this biochar amendment on the biogas production, especially the ratio between H2, CH4 and CO2. Analysis of the various results and the relationship between biogas production, biochar properties and microbial ecology will be carried out at the end of the PhD project, and will culminate in the publication of the thesis and scientific articles. If relevant, IP protection will be considered.

This project will be developed under the supervision of Dr. Mathieu Etienne at LCPME and Dr. Emmanuel Guedon at LRGP, in collaboration with Dr. Anthony Dufour and Dr. Frédérique Changey at Université de Lorraine and the group of Prof. Manuel Garcia-Perez from Washington State University (WSU).

LCPME will provide resources for electrochemical measurement of surface reactivity, especially with using a variety of instruments from the platform of spectroscopy and microscopy of interfaces, especially atomic force microscopy, scanning electrochemical microscopy, XPS and Raman spectrometry. LCPME will also provide facilities and methodology for microbial ecology analysis of biofilms (platform of environmental molecular biology). LRGP will provide equipment and expertise for elaboration of biochar of controlled composition and properties and online gas analysis for determination of the H2, CH4 and CO2 ratio, in collaboration with the experimental farm of La Bouzule. The project will also involve Prof. Manuel Garcia-Perez at WSU on the topic of biomass valorization. WSU will bring its extensive molecular models of biochar structures and a deep understanding on the biochemical mechanisms on biochar surfaces.

Profile and skills required

This project is multidisciplinary in nature, and the candidate will preferably have a background in physical-chemistry or materials science and a strong interest in complex biological systems.

A background in microbiology or bioprocessing may also be suitable for this project, but the student should demonstrate a keen interest in physicochemical analysis. A first experience in electrochemistry or bioelectrochemistry would be highly appreciated.

Context

Université de Lorraine has collaborated with Washington State University (WSU) as part of an Erasmus+ program supported by LCPME. An international research project (funded by CNRS and LUE and led by LRGP) is underway on biomass (2022-2026).