Directrice de recherche

I am studying the solution chemistry of metal ions in water and in innovative liquid systems, such as Ionic Liquids (ILs), Aqueous Biphasic Systems (ABS) and Deep Eutectic Solvents (DES).
- ILs are salts which melting temperature is equal or below T = 100°C. Some are hydrophobic enough to induce a meniscus when contacted with water phases, thus allowing metal extraction. Being salts, their solvating properties are totally different from those of traditional molecular organic solvents (benzene, toluene, kerosene etc.). Therefore, they can offer extraction efficiencies very different from what is possible with molecular solvents. However, they are rather expensive and their toxicity is still largely unknown.
- ABS are ternary systems composed of water plus two other compounds (ILs, polymers, inorganic salts, acids etc…). Depending on used chemical conditions (mass percentages and temperature) these mixtures can be either in a monophasic or a biphasic state, thus allowing metal extraction in a reversible way. In such systems, water is the main ingredient, thus lowering costs, but the molecular phenomena at the heart of the biphasic/monophasic changes are still poorly understood, limiting the control and use of such systems for applied studies. Interestingly, some of their constituents (polymers, salts, some ILs) are green enough to be accepted at the industrial scale.

- DES are binary mixtures with melting temperatures below what is predicted by classical thermodynamics. Some of them are also hydrophobic enough to induce a meniscus when contacted with water phases. Some of their ingredients can be bio-sourced, or rather non-toxic (and cheap) materials, rendering them an interesting approach for industrial applications. However, at the moment, their study in view of metal extraction is in its infancy.
The fundamental aim of my research work is to understand and model, if possible, the extraction mechanisms and mass transfer kinetics of metal ions from one phase to either ILs, ABS or DES. Recently, neutron scattering and other optical techniques are used (ESRF and ILL) to follow micelle formation of ILs in ABS as a function of temperature, sample composition or time. On a more classical experimental approach, analytical techniques allow to determine the composition of the upper and lower phase as a function of chemical conditions. On this basis, extraction mechanisms can be proposed, translated into mathematical equations, and fitted to the experimental results.
The applied perspective of my work is to propose, test and implement from the lab scale to the (pre)-industrial scale, innovative ways to recycle metals ions from any type of wastes, such as batteries (Ni, Co, Ln, Li etc.), PEMFC (Proton Exchange Membrane Fuel Cells) (Pt, Ni, Co etc.) or other industrial liquid or solid wastes by using innovative means such as ILs, ABS or DES. These methods should comply as much as possible with the objective of a greener world. In this frame, past projects have dealt with permanent magnets, NiMH batteries, or pickling baths, in close collaboration with industrial partners and French or European academic colleagues. In the last 6 years, three patents have been submitted on these topics.
Current applied projects (2021) concern new pickling baths, fine incineration ashes, polluted soils remediated with plants and radioactive liquid samples.

Activités / CV

keywords: Ionic liquids; solution chemistry, metallic ions; liquid/liquid extraction, Deep Eutectic Solvents; Aqueous Biphasic Systems, Ionic Liquids.
Publications (peer review): 104; Book chapters: 5
Some recent papers:
Matthieu Gras, Nicolas Papaiconomou, Nicolas Schaeffer, Eric Chainet, Farouk Tedjar, Joao Coutinho, Isabelle Billard
Novel ionic liquids based acidic aqueous biphasic systems for simultaneous leaching and extraction of metal ions, Angew. Chem. Int. Ed., 57(2018)1563.
DOI : 10.1002/anie.201711068

N. Schaeffer, H. Passos, M. Gras, V. Mogilireddy, J. Leal, G. Perez-Sanchez, J. Gomes, I. Billard, N. Papaiconomou, J. A. P. Coutinho,
Mechanism of ionic liquid-based acidic aqueous biphasic systems formation, PCCP, 20(2018)9838.
DOI : 10.1039/c8cp00937f

N. Schaeffer, I. Billard, N. Papaiconomou, J. Coutinho
Recovery of metals from waste electrical and electronic equipments (WEEE) using ionic liquids, Critical Rev. Environ. Sci. Technol. (2018)1-64
DOI : 10.1080/10643389.2018.1477417

V. Mogilireddy, M. Gras, N. Schaeffer, H. Passos, L. Svecova, N. Papaiconomou, J. Coutinho, I. Billard,
Understanding the fundamentals of acid-induced ionic liquid-based aqueous biphasic system, PCCP, 20(2018)16477 ;
DOI : 10.1039/C8CP02862A

N. Schaeffer, M. Gras, H. Passos, V. Mogilireddy, C. Mendonça, E. Pereira, E. Chainet, I. Billard, J. Coutinho, N. Papaiconomou
Synergistic aqueous biphasic systems : a new paradigm for the ‘one-pot’ hydrometallurgical recovery of critical metals, ACS Sus. Chem. Eng. 7(2019)1769
DOI: 10.1021/acssuschemeng.8b05754

I. Billard
Green solvents in urban mining, Current opinion in green and sustainable chemistry, 18(2019)37.

R. Lommelen, T. Vander Hoogerstraete, B. Onghena, I. Billard, K. Binnemans,
Model for metal extraction from chloride media with basic extractants: a coordination chemistry approach, Inorg. Chem., 58(2019)12289   DOI : 10.1021/acs.inorgchem.9b01782

Isabelle Billard, Corinne Lagrost,
Liquides ioniques, espoirs et raison, de la recherche à l’industrie
Techniques de l’Ingénieur (2020), n° AF6712v2, base documentaire : TIB106DUO.

Eris Sinoimeri, Victor Maia Fernandes, Jérôme Cognard, Jorge Fernando Brandao, Lenka Svecova, Ismaël Guillotte, Isabelle Billard
Uncommon biphasic behaviour induced by very high metal ion concentrations in HCl/H2O/[P44414]Cl (tributyltetradecylphosphonium chloride) and HCl/H2O/polyethene glycol-600 systems PCCP, 22(2020)23226, DOI : 10.1039/D0CP03689G

I. Billard,
Are molecular solvents, aqueous biphasic systems and deep eutectic solvents meaningful categories for liquid-liquid extraction?
CR Acad. Sci. Chimie, 25(2022)67. DOI : 10.5802/crchim.151

G. Meyer, R. Schweins, T. Youngs, J. F. Dufrêche, I. Billard, M. Plazanet
How temperature rise induces phase separation in aqueous biphasic solutions, J. Phys. Chem. Lett. 13(2022)2731   DOI: 10.1021/acs.jpclett.2c00146